Field

The present application relates to a shower control device and to a shower system, as well as to methods for controlling a shower control device and a shower system.

Background

Showers utilise two main consumables, water and energy to heat the water. The energy utilised is typically provided in the form of gas or electrical heating. It is generally desirable, both for environmental and financial reasons, to reduce or limit the consumption of water and energy by the shower.

One known technique for controlling the operation of a shower is to have a mechanical valve which is generally maintained in a closed position so that no water can flow through the valve and out of the shower head. A mechanical button is provided which, when pushed in by a user, causes the valve to open and allows water to flow out through the shower head. The valve is configured to close in an automatic fashion over a predetermined time, pushing the button back out to its initial (closed) position to terminate the flow of water through the shower. This automatic closure of the valve may be accomplished by providing some form of resilient (e.g. spring) mounting for the button and/or by utilising the pressure of water flowing through the shower. In many implementations, the predetermined time over which the valve closes is set to be relatively short compared with the shower duration for most users. Therefore a user generally has to repeatedly activate the push button to maintain or restart a flow of water during the shower.

In practice, this type of shower control is primarily used in communal installations, for example in camp-sites, swimming pools, gyms, beaches, and so on. This type of control is particularly common if there is a concern that a user may exit the shower without turning off the water, which could potentially lead to a significant waster of water. The shower control described above helps to mitigate this risk, in that flow of water through the shower terminates within a predetermined time period from the user leaving the shower, once the mechanical valve has returned automatically to the off (closed) position.

Although the use of such a shower control is reasonably effective in such communal installations, it has various drawbacks. For example, the need to repeatedly operate the mechanical button to restart the water flow is somewhat cumbersome. In addition, the flow may terminate while a user has his or her eyes closed, such as for washing hair, in which case the user may struggle to see the button to press to obtain more water for rinsing the hair.

With increasing utility costs for water, gas and electricity, there is an ongoing desire for shower installations which help to reduce the consumption of such consumables.

Summary

The invention is defined in the appended claims. In one aspect, a shower control device is provided herein comprising a valve configured to be inserted into a path from a hot water supply to a shower. The valve is further configured to receive cold water from a cold water supply. The shower control device is configured to open or close the valve to control a flow of hot water from the hot water supply through the valve to a hot water feed of the shower. The shower control device is further configured to maintain an approximately constant flow of water from the valve to the hot water feed by using the received cold water to compensate for a reduction in the flow of hot water from the hot water supply through the valve to the hot water feed of the shower as the valve closes. The shower control device further comprises a control system configured to maintain the valve in an open condition over a first phase of the shower, and to transition the valve from the open condition to a closed condition over a second phase of the shower.

The shower control device may include a value stored in the control system which specifies a predetermined duration for the first phase of the shower.

The shower control device may implement the predetermined duration for the first phase of the shower to be in the range 2 to 30 minutes, preferably 4 to 20 minutes, preferably 6 to 15 minutes.

The shower control device may implement the first phase of the shower having a duration T1 and the second phase of the shower having a duration T2, wherein the ratio T2/T1 is in the range 1- 25%, preferably in the range 2-20%, preferably in the range 3-15%.

The shower control device may implement the second phase of the shower having a duration T2, wherein T2 is in the range 10-200 seconds.

The shower control device may implement the second phase of the shower having a duration T2 and AF which represents the difference between (i) the flow of hot water from the hot water supply to the hot water feed of the shower with the valve in the open condition at the start of the second phase, and (ii) the flow of hot water from the hot water supply to the hot water feed of the shower with the valve in the closed condition at the end of the second phase, and wherein at a midpoint time into the second phase, T2/2, the flow of hot water from the hot water supply to the shower is less than AF/2.

The shower control device may further comprise a flow detector for detecting a flow of water to the hot water feed of the shower corresponding to the start of the first phase of the shower.

The shower control device may respond to a termination of the shower during or after the second phase by having the control system configured to maintain the valve in the closed condition for a predetermined wait time.

The shower control device may respond to a termination of the shower during the first phase by having the control system configured to transition directly to the end of the first phase.

The shower control device may further comprise a timer to determine the duration of the first phase, wherein in response to a termination of the shower during the first phase, the control system is configured to suspend a timer for a predetermined period, and if the shower is restarted during the predetermined period, the timer is restarted.

The shower control device may further comprise an actuator to open and close the valve, optionally wherein the actuator comprises a stepper motor. In some implementations of the shower control device, the valve may include a piston which is moved by the actuator in a linear direction to open or close the valve. The actuator may include a shaft in threaded engagement with the piston, wherein rotation of the shaft causes the piston to move in the linear direction.

The shower control device may further comprise at least one communications interface for connecting to a smart device app for configuring the shower control device.

The shower control device may further comprise at least one communications interface for connecting to a remote system or service, such as a cloud-based server for storage of data and further analytics. Note that in some cases, such communications to a remote system or service may be implemented using (via) the smart device app.

The shower control device may further comprise a temperature sensor for measuring the temperature of water passing through the valve to the hot water feed of the shower.

In some implementations, the control system may include a profile specifying a track of temperature against time during the transition of the second phase. The control system may be configured to use temperature measurements provided by the temperature sensor for controlling the valve to follow the profile.

Also provided is a shower control system including a shower control device as described above and a smart device having an app for configuring the shower control device.

The shower control system may further comprise multiple shower control systems, and the smart device app is configured to control each of the multiple shower control systems.

In another aspect, a method of operating a shower control device is provided comprising: providing a valve inserted into a path from a hot water supply to a shower, the valve being configured to received cold water from a cold water supply; operating the shower control device to open or close the valve to control a flow of hot water from the hot water supply through the valve to a hot water feed of the shower; maintaining an approximately constant flow of water from the valve to the hot water feed by using the received cold water to compensate for a reduction in the flow of hot water from the hot water supply through the valve to the hot water feed of the shower as the valve closes; and controlling the shower control device to maintain the valve in an open condition over a first phase of the shower, and to transition the valve from the open condition to a closed condition over a second phase of the shower.

The method may further comprise setting the duration of the first phase to support a reduction in the usage of water and energy by the shower.

The approach described herein may operate the shower control device to emulate the depletion of hot water from the hot water supply as the shower progresses through the second phase.

In another aspect, a shower system is provided. The shower system is configured to provide water at a temperature according to user preference during a first phase of the shower. The shower system is further configured to convert from the first phase of the shower to a second phase of the shower in response to a predetermined level of usage of the shower during the first phase. During the second phase of the shower, the shower system is further configured to perform a reduction in the temperature of water supplied from the shower. The reduction is spread over a period of at least 10 seconds within the second phase.

In some implementations, the predetermined level of usage of the shower during the first phase corresponds to a predetermined time duration and/or a predetermined flow volume of water from the shower. The predetermined time duration for the first phase of the shower may be in the range 2 to 30 minutes, preferably 4 to 20 minutes, preferably 6 to 15 minutes.

In some implementations, the first phase of the shower has a duration T1 and the second phase of the shower has a duration T2, wherein the ratio T2/T1 is in the range 1-50%, preferably in the range 2-40%, preferably in the range 3-25%.

In some implementations, the reduction is spread over a period in the range 10-400 seconds, preferably in the range 20 to 200 seconds.

In some implementations, during the second phase of the shower, the temperature of the water supplied from the shower may be reduced by at least 5°C, preferably by at least 10°C, preferably by at least 15°C.

In some implementations, at the end of the second phase, the temperature of water supplied from the shower may have a temperature in the range from the cold water temperature up to 30°C, preferably in the range 18 to 25°C.

In some implementations, the reduction in temperature for the first half of said period may be greater than the reduction in temperature for the second half of said period.

In some implementations, the shower system may be configured to prevent further water being supplied from the shower at the end of the second phase.

In some implementations, at the start of the second phase, the shower system (unit, etc) is controlled to start a reduction in temperature of the shower water. In other words, the start of the reduction in the shower water temperature may be considered as representing the transition from the first phase to the second phase. The reduction in shower water temperature at the start of the second phase is not a sudden (e.g. step) drop in water temperature, but rather the start of a gradual decrease in the shower water temperature which is spread out over a more prolonged period encompassed by the second phase. In other words, the shower water temperature may be continuously reduced on an ongoing basis over this prolonged period of the second phase. The prolonged period may (for example) be at least 10 seconds in length, and may be longer, such as at least 20 seconds, at least 30 seconds, at least 1 minute, at least 2 minutes, at least 5 minutes or at least 10 minutes (or any value or range therebetween).

In contrast to a sudden drop (step down) in shower water temperature, which may be an unpleasant experience for a user and possibly also a physical shock, the gradual decrease in the shower water temperature which is spread over the prolonged period mentioned above provides the user with a gentler notification that the shower control unit has transitioned to the second phase. This then allows a user to manage his or her shower based on the understanding that there is only a limited duration remaining for the shower.

In some implementations, the shower system may further comprise a control unit which stores one or more of the following parameters: the predetermined level of usage for ending the first phase; a predetermined value for said period; a predetermined duration for the second phase; and/or a predetermined minimum temperature for the water supplied during the second phase.

In some implementations, one or more of the specified parameters may be configurable according to a command to the control unit from an administrator of the shower system.

In some implementations, different sets of specified parameters may be configured for different users of the shower system.

In some implementations, the shower system may further comprise an interface for communicating with a smart device and associated app, whereby the smart device may be used for setting the one or more parameters stored within the control unit.

In some implementations, the shower system may further comprise an interface for communicating with a remote system or service, such as a cloud-based server for the storage of data and/or further analytics. Note that in some cases, such communications to a remote system or service may be implemented using (via) the smart device app.

In some implementations, the shower system may further comprise at least one flow detector and/or at least one temperature sensor to provide information relating to water flowing into, through, and/or out of the shower system. The shower system may be configured to use such information for controlling a shower.

In some implementations, the shower system may include a shower unit having a valve system and valve control unit. The valve control unit may be configured to control the valve system to implement the first and second phases as set out above.

In some implementations, the shower unit may be configured to receive cold and hot water supplies. The valve system may comprise a first valve for controlling the cold water and a second valve for controlling the hot water.

In some implementations, the shower unit may be configured to receive cold and hot water supplies. The valve system may comprise a mixer valve for combining the cold water and hot water in appropriate proportions for providing water at a controllable temperature.

In some implementations, the shower system may include a shower unit and a valve system and a valve control unit separate from the shower unit. The valve control unit may be configured to control the relative proportions of hot and cold water flowing through the valve system to the shower unit.

In another aspect, a shower unit is configured to: (i) during a first phase of a shower, provide water at a temperature according to user preference; (ii) convert from the first phase of the shower to a second phase of the shower in response to a predetermined level of usage of the shower during the first phase; and (iii) during the second phase of the shower, perform a reduction in the temperature of water supplied from the shower, wherein said reduction is spread over a period of at least 10 seconds within the second phase.

Some implementations of the shower unit may include (i) a valve system for receiving hot and cold water input and (ii) a valve control unit, wherein the valve control unit is configured to control the valve system to implement the first and second phases in supplying water to a shower head. In another aspect, a method of operating a shower system may be provided. The method comprises the steps of: during a first phase of a shower, providing water at a temperature according to user preference; converting from the first phase of the shower to a second phase of the shower in response to a predetermined level of usage of the shower during the first phase; and during the second phase of the shower, performing a reduction in the temperature of water supplied from the shower, wherein said reduction is spread over a period of at least 10 seconds within the second phase.

In another aspect, a machine-implemented method is provided comprising: collecting usage data for a shower system, said usage data including at least one of hot water consumption, overall water consumption and power consumption; performing an analysis of the collected usage data for the shower system in comparison with collected usage data from one or more other shower systems; and using the analysis to require or motivate a user of the shower system to reduce at least one of hot water consumption, overall water consumption and power consumption.

The method may further comprise communicating with the user of the shower system to motivate the user of the shower system to reduce at least one of hot water consumption, overall water consumption and power consumption. In some cases, the communicating is performed based on the collected usage data from the shower system and optionally from the collected usage data from one or more other shower systems. In some cases, the communicating is performed based on at least one of: heuristics of the collected usage data; gamification based on the collected usage data; nudges based on the collected usage data; cognitive saliency based on the collected usage data; and rational argument based on the collected usage data.

The method in some implementations may further comprise providing the user of the shower system with a reward or benefit to motivate the user of the shower system to reduce at least one of hot water consumption, overall water consumption and power consumption. In some implementations of the method, the analysis is performed by a cloud server on the collected usage data from the shower system together with the collected usage data from the one or more other shower systems. The shower system may be located in a domestic, commercial or institutional environment.

In another aspect, a system is configured to: collect usage data for a shower system, said usage data including at least one of hot water consumption, overall water consumption and power consumption; perform an analysis of the collected usage data for the shower system in comparison with collected usage data from one or more other shower systems; and use the analysis to require or motivate a user of the shower system to reduce at least one of hot water consumption, overall water consumption and power consumption.

In some implementations, such a system may be operated to collect usage data for multiple different shower systems, the usage data specifying at least one of hot water consumption, overall water consumption, water temperature and power consumption. This usage data may be provided to a remote system, such as a cloud server, which can then analyse and compare the usage data for multiple shower systems. Such an analysis may involve comparing usage data for different users, including analysis (comparisons) by location, by person, by date/time, and/or by any other parameters of interest. In some implementations, based on the results from the analysis above, the remote server (remote system) may automatically adjust the operation of individual shower systems as appropriate. For example, if the analysis shows that a user generally has showers that are significantly hotter than other users, then the duration of the first phase for this user may be reduced to provide a more equitable allocation of power consumption. Additionally (or alternatively) the results of the analysis may be used to inform and influence user behaviour. For example, a user who has relatively high temperature showers compared with other users might be offered an incentive to reduce their hot water consumption such as points under a hotel reward scheme.

In another aspect, a machine-implemented method is provided comprising: collecting usage data for a shower system, said usage data including at least one of hot water consumption, overall water consumption and power consumption; performing an analysis of the collected usage data for the shower system to determine whether or not the shower system has been inactive for a predetermined calendar period; and in response to determining that the shower system has been inactive for a predetermined calendar period, perform at least one of: (i) automatically flush water through the shower system; and (ii) generate an alert for an operator to flush water through the shower system.

In another aspect, a system is configured to: collect usage data for a shower system, said usage data including at least one of hot water consumption, overall water consumption and power consumption; perform an analysis of the collected usage data for the shower system to determine whether or not the shower system has been inactive for a predetermined calendar period; and in response to determining that the shower system has been inactive for a predetermined calendar period, perform at least one of: (i) automatically flush water through the shower system; and (ii) generate an alert for an operator to flush water through the shower system.

Such an approach may be implemented by determining whenever a shower unit has been activated - this may be assessed for example by using a flow meter to monitor the flow through the shower to obtain usage information. When the usage data indicates that the flow through the shower exceeds a set amount, such that all water held within the shower system from a previous usage has been fed through the shower head to be replaced with fresh water, then this is identified as a shower having occurred. The shower system may collect and store the time and date of each detected shower. As long at the shower system is used without overly long gaps between showers, this prevents the potential growth of unwanted organisms in the water held within the shower system.

To keep unwanted organisms under control, the shower system may be set with a threshold period (such as some number of days). The stored information regarding the time/date for the most recent shower may be monitored and analysed on an ongoing basis to determine for the most recent shower whether it occurred more than the threshold period prior to the current date. For example, if the threshold period is specified as a calendar period such as a week, a check is made to see whether the last shower performed by the shower system is over a week old. If not, no action may be needed; however, if so, the shower system may control the shower to flush through with enough water to remove any microorganisms or other potential contaminants. This may be accomplished either by performing the flush through automatically such as by using remote control of the valve controls described above, and/or by sending an alert to an operator to trigger such a flush. The threshold period may for example be a number of days, such as 3 days, 5 days, 7 days, 10 days, 14 days, 20 days or 30 days (or any number of days therebetween or any number of days in a range that has a lower and upper limit specified by any pairing of these numbers).

In some cases, the shower system may include a control facility provided in a server or cloud system for preventing potential water contamination as above. This control facility may collect and analyse usage information from multiple different shower units, such as might be found in a hotel, hotel chain, university hall (or halls) of residence and so on. The analysis may be used to determine whether each shower (from the multiple different shower units) has been operated for a shower or similar within the threshold period. If this is not the case, i.e. if a shower unit has not been utilised within the past threshold (calendar) period, the control facility may automatically perform a flushing operation of the relevant shower(s) using remote control of the valves on the shower unit as described above (or any other suitable approach). The control facility may also generate an alert if a shower unit has not been used within the past threshold period to trigger or suggest the subsequent performance of such flushing, e.g. by a human operator such as cleaning staff.

Also disclosed herein are a shower system and method configured to receive an identity of a user of a (the) shower system; to collect information regarding water usage by the user during a shower in the shower system, the monitored information including a duration and/or volume of the flow of water during the shower; and to provide to a server the user identity and collected water usage information in association with one another. Such a method and/or shower system may be configured for use in a communal setting, such as a university hall of residence, for example to allow individual users of a communal shower facility to track and manage their own respective water usage.

The shower system (or method) may be configured to receive the user identity using a personalised RF ID device, by using biometric recognition such as fingerprint or palm scanning, by using Bluetooth or Wi-Fi connectivity, by using a smart card embedded with a unique identifier which users can tap or swipe on the shower system, and/or by using a QR code, a PIN code or a password.

The shower system of the machine-implemented methods and corresponding systems may be implemented by the shower system or shower unit described above. It is emphasised that while certain features are described in the context of particular implementations or embodiments, it is expressly contemplated that such features may generally be used in other implementations or embodiments unless it is clear to the skilled person that such a combination is not viable.

Brief Description of the Figures

Various implementations of the claimed invention will now be described by way of example only with reference to the following drawings:

Figure 1 is a high-level schematic diagram providing an example of a shower system as disclosed herein.

Figure 2 is a high-level schematic diagram providing an example flowchart for configuring the shower system of Figure 1 . Figures 3A and 3B provide high-level schematic diagrams shown an example of the operation of a valve in the shower system of Figure 1.

Figure 4 is a high-level schematic diagram providing an example flowchart for operating the shower system of Figure 1 .

Figure 4A is a schematic diagram showing examples of the variation of water temperature with time for a shower system such as shown in Figure 1 .

Figure 5 is a high-level schematic diagram providing an example of a valve control unit for use in a shower system as disclosed herein.

Figures 6A, 6B, 6C and 6D are high-level schematic diagrams providing an example of valves for use in a shower system as disclosed herein.

Figure 7 is a high-level schematic diagram providing another example of a shower system as disclosed herein.

Figure 8 is a high-level schematic diagram providing an example of the valve configuration in the shower system of Figure 7.

Figure 9 is a high-level schematic diagram providing another example of the valve configuration in the shower system of Figure 7.

Figure 10 is a graphical plot showing an example procedure of reducing the water temperature in a shower as described herein.

Figure 11 is a high-level schematic diagram providing an example of a cloud-based shower management system as disclosed herein.

Figure 12 is a high-level schematic diagram providing another example of a shower system as disclosed herein, while Figures 12A and 12B show an example of the operation of a valve in the shower system of Figure 12.

Figure 13 is a high-level schematic diagram providing another example of a cloud-based shower management system as disclosed herein.

Detailed Description

Many people agree that water and the environment are important, but they would just like it to be easier to do their bit. The approach described herein is designed to encourage people to behave more sustainably and to own their experience by choosing to make a positive impact and save energy and/or water. Just as shower technology is changing what is possible with new products, a parallel transformation in the way people interact with water enables people to do more with less by using a new approach to demand management based on nudge theory and social norming.

Changing what people think by coercion or persuasion is costly and rarely works. A “nudge” or other form of encouragement is a far better way to influence decisions and behaviour in water and energy conservation. The approach described herein may be used to nudge individuals into making better decisions while still maintaining their freedom of choice. At the same time, a shower system as described herein (referred to as a ShowerKap system) may include a smart box (or device) acting as a control system to allow a suitably authorised super-user (administrator) real-time monitoring and control of various functional components of the shower system (such as valves) together with their operating parameters. The provision of detailed system wide usage data, including date, time, duration and water volume used, makes it easier to manage and reduce water and heating use and monitor system inactivity (such as to address health risks, for example Legionella or other potential contaminants). By way of illustration, for a university campus with 9,000 students, the ability to limit shower duration to 4 minutes could save approximately 195 m litres of water, 1 m kg CO2 and £1 .5 m per year.

As described herein, a shower system may be provided to gradually reduce the flow of hot water over a preset time period, thereby simulating the sensation of the hot water supply running out. A shower system is also provided that provides nudges relating to instantaneous behaviour so as to prompt the user to finish their shower more quickly to help achieve savings as mentioned above, but without compromising their comfort.

Figure 1 is a high-level schematic diagram providing an example of a shower system 100 as disclosed herein. The shower system 100 includes a smart device 120, a valve control unit 130, an actuator 135 (which may be provided in some cases as part of the valve control unit 130), a valve 140 and a shower unit 150.

In one implementation, the smart device 120 is used to control or set the valve control unit 130. The smart device 120 is typically a handheld device such as a smartphone, tablet, etc, which includes a memory for storing program instructions and data 126 and a processor for executing the instructions and using the data as required. The program instructions generally implement an operating system, such as Android or iOS, which allows applications (apps) 124 to be installed and executed. The smart device 120 further includes a user interface 122 which generally comprises a mix of hardware and software. The user interface 122 comprises a display screen to provide output from the smart device to a user, the display screen being implemented as a touch-screen to allow a user to provide input to the smart device. A smart device may also be provided with other hardware to support user input and/or output, such as a microphone for audio input, a camera for visual input, and a speaker for audio output. The operating system of a smart device includes user interface software which may be utilised by applications on the smart device to provide user input/output specific to the requirements of each application. Accordingly, the user interface 122 can be regarded as a combination of hardware and software used to provide output to the user and to receive input from the user. The smart device 120 further includes one or more communications interfaces 128 for data communication with other devices. These communications interfaces 128 may be based on wired connectivity, such as USB, or wireless connectivity, such as Bluetooth or wireless LAN.

The shower unit 150 is configured to receive a cold water supply 110 and a hot water supply 112 and to provide an output flow of water for a user of the shower system 100 via a shower head. The cold water supply 110 and hot water supply 112 may be gravity fed or utilise a pump (not shown in Figure 1) to provide a power shower with a greater flow of water to and through the shower unit 150. The hot water supply 112 may be provided from a hot water storage tank (not shown), the hot water having already been heated for example by a gas-fired boiler, an electric immersion heater, a heat pump or solar heating. Alternatively, the hot water supply 112 may be taken from a combi-boiler (not shown) which heats water in real-time to provide hot water on demand. The hot water from the hot water supply 112 passes through, and is controlled by, valve 140, as described in more detail below. In contrast, the cold water from the cold water supply 110 may pass directly to the shower unit 150. However, there is also a branch pipe 111 which leads from the cold water supply 110 to the valve 140. The use of this branch pipe 111 is described in more detail below. Note that rather than having a branch pipe 111 taken from the cold water supply 110 as shown in Figure 1 , in some installations there may be two cold water supply pipes, a first cold water pipe leading to the shower unit 150 and a second separate cold water pipe leading to the valve 140.

The shower unit 150 is generally conventional and so will only be described here briefly (since it is already known to the skilled person). The shower unit 150 typically contains a shower head and a user control to switch the flow of water on and off. The shower unit usually contains a further user control to adjust output water temperature by altering the relative proportion taken from the cold and hot water supplies 110, 112 for the shower output. The shower unit 150 may also be provided with a user control to adjust the overall output flow rate of water from the shower head.

As shown in Figure 1 , the hot water supply 112 passes through a valve 140. The valve can be open, to allow hot water from the hot water supply 112 to pass unimpeded to the shower unit 150, or closed to prevent the shower unit 150 from receiving water from the hot water supply 112. The valve 140 can also be controlled to be partly open to provide one or more intermediate states (rather than just a binary option between fully open and fully closed).

The valve 140 is further used to control the flow of cold water from the cold water supply 110 that passes along branch pipe 111 into the valve. In general terms, the valve 140 acts to provide an approximately constant flow of water from the valve 140 to the shower unit 150. (Approximately should be understood herein as indicating a flow that remains constant within 20%, within 15%, within 10%, within 5%, within 2%, or within 1 %). More particularly, the shower unit 150 has two inputs, the first a cold feed 151 for directly receiving cold water provided by the cold water supply 110, and the second a hot feed 152 for receiving the approximately constant flow of water from the valve 140. As explained above, the valve 140 can be opened to allow hot water from supply 112 to pass unimpeded to the hot water feed 152 of the shower unit 150, or closed to prevent water from the hot water supply 112 passing through the valve 140 to the shower unit 150. In the former case, the valve 140 further acts to close off the cold water supply 110 from travelling via branch pipe 111 into (and through) the valve 140. Conversely, in the latter case the valve 140 further acts to open and allow cold water from the cold water supply 110 to travel via the branch pipe 111 into the valve 140; this cold water is then supplied from the valve 140 to the hot feed 152 of the shower unit 150. Furthermore, if the valve 140 is in an intermediate position, between the open and closed positions, then the valve 140 receives an intermediate flow of water from the hot water supply 112 and an intermediate flow of water from the cold water supply 110 via the branch pipe 111. The valve then combines these two intermediate flows to provide a flow of water to the hot feed 152 of the shower unit 150 which has approximately the same overall flow rate as when the valve 140 is positioned just to supply water from a single source (the hot water supply 112 or branch pipe 111).

In other words, if the valve 140 is operated to reduce the flow of water from the hot water supply 112 (referred to herein as closing the valve 140), then the valve simultaneously acts to increase the flow of water from the branch pipe 111 to provide an amount of water that approximately matches and hence compensates for the reduced supply of water taken from the hot water supply. Conversely, if the valve 140 is operated to increase the flow of water from the hot water supply 112 (referred to herein as opening the valve 140), then the valve simultaneously acts to decrease the flow of water from the branch pipe 111. This then ensures that overall, the valve 140 provides an approximately constant flow of water to the hot water feed 152 of the shower unit 150 (even if the flow from the hot water supply is reduced to zero).

As shown in Figure 1 , the valve control unit 130 operates the actuator 135 to open or close the valve 140. It will be appreciated that as the valve 140 starts to close, the proportion of water supplied to the hot water feed 152 taken from the hot water supply 112 starts to fall, and there is a corresponding increase in the proportion of water taken from the cold water supply 110 via the branch pipe 111. The net effect is that the temperature of the water arriving at the hot water feed 152 starts to fall. In some implementations, the shower unit 150 may be able to compensate for this initial decrease in the hot water flow rate by reducing the amount of cold water from the cold water feed 151 emanating from the shower head, thereby preserving an approximately stable temperature. However, as the actuator 135 further closes the valve 140, the temperature of the water supplied from the shower unit 150 will inevitably fall. When the valve 140 has been fully closed by the valve control unit 130, then the shower unit 150 may only receive cold water from the cold water supply 110. In particular, the cold water will be partly received from the cold water feed 151 directly from the cold water supply 110, and partly from the hot water feed 152 indirectly from the cold water supply (namely, via branch pipe 111 and valve 140). In these circumstances, the water output provided from the shower unit to a user would take the temperature of the cold water supply 110. Accordingly, it is only the temperature of the water output from the shower that changes as the valve 140 is actuated, not the volume or flow rate of water output from the shower. As explained below, this matches (emulates) the effect of the hot water cylinder being depleted of hot water.

As described in more detail below, the shower system 100 is intended in practical terms to limit the time a user spends in the shower. Thus the valve control unit 130 is configured to have the valve 140 in an open condition when a user initiates a shower. However, after the expiry of a predetermined duration for the shower, which may be set using the smart device 120 and saved into the valve control unit 130, the valve control unit 130 automatically activates the actuator 135 to move from the open position to the closed position. The predetermined shower duration, during which the valve remains in the open condition, can be regarded as a first phase of operation. The transition from an open position of the valve to a closed position of the valve 140 does not take place instantaneously, but rather at a measured pace corresponding to a second phase of operation. For example, the transition time, i.e. the time for the valve control unit to operate the actuator to switch the valve 140 from a fully open state to a fully closed state might be in the range say 10 seconds to 150 seconds, or in the range 20 seconds to 120 seconds.

In practice, once the shower unit 150 no longer provides hot (or even warm) water to a user of the shower, the user normally terminates the shower. The transition time is set to allow a user to detect the gradually decreasing temperature of the water output by the shower unit 150 and to conclude the shower in an orderly manner, for example with adequate time to rinse out shampoo, soap, etc prior to full closure of the valve 140 and the water supplied by the shower unit 150 becoming cold.

Overall, the user impression of the valve 140 closing in this manner is analogous to the situation in which the hot water in a hot water cylinder becomes fully depleted (due to use of the shower). In such a situation, the system would continue to draw water from the hot water cylinder, but this water would be cold, having only just entered the hot water cylinder without yet being heated. It will be appreciated that although the user impression might be that the hot water cylinder has been depleted, this is not actually what has happened at a system level. Rather, in the shower system 100 of Figure 1 , the hot water supply 112 may still have hot water available, however after the second phase, this hot water does not reach the shower unit 150 because of the closed valve 140 and the hot feed 152 is instead being used to provide cold water via branch pipe 111 to the shower unit 150.

(For the avoidance of doubt, we note that in shower system 100, the hot water supply may be provided by a combi boiler. Such a boiler does not have a hot water cylinder to become depleted, however, this may still represent the impression of a user as the valve 140 slowly closes to reduce and then cut off the hot water supply 112, to be replaced with cold water via branch pipe 111).

As mentioned above, a user will generally conclude their shower in response to the falling temperature of the water supplied to and from the shower unit 150. In effect this limits the time that a user spends in the shower to the duration of the first phase (plus some of the transition time corresponding to the second phase for the valve 140 to close). As described in more detail below, the duration of the first phase and also the duration of the second phase may be configured into the valve control unit 130. Restricting a shower duration in this manner helps to save resources (water, energy and cost) because the shower duration (based on the first and second phases) is set to be shorter than the duration of a shower that a user would otherwise take if the hot water were not cut out by valve 140. Accordingly, the shower system 100 of Figure 1 provides users with clear environmental and financial benefits.

Furthermore, in a family situation, the shower itself can be considered a resource. For example, multiple people in a family may want to use the shower before travelling to school, work, etc, or likewise in the evening before going out. If family members like to spend too long in the shower, this can lead to contention about the length of time for which the shower is occupied by certain people and how this impacts other family members. The shower system 100 of Figure 1 helps to alleviate this situation by restricting in practice the shower duration for each family member. Moreover, with such an approach, time in the shower is fairly distributed, because the limited timing for shower duration (the first and second phases) is applied consistently by the valve control unit 130 for all users.

Even if there is no contention for use of a shower, restricting the predetermined shower duration may help a user improve his or her timeliness. For example, if a user has to arrive at school by a given time each weekday, ensuring they do not spend overly long in the shower as part of getting ready for school avoids one possible cause of delay. The shower system 100 of Figure 1 may also be provided for a user who is still generally able to live at home but who suffers to some extent from dementia or a similar ailment. For example, if the water cools as described herein, this provides a strong physical stimulation to remind the user to end the shower and turn off the flow of water from the shower.

Figure 2 is a high-level schematic diagram providing an example flowchart of operations performed to allow an app 124 to configure the shower system 100 of Figure 1. The method includes operation 210 for downloading and installing the app 124 which may be made available, for example, from an app store or any other suitable source, such as the web-site of the provider of the shower control device. This may involve a user registration procedure to obtain the app 124.

At operation 220, the smart device 120 (e.g. a smartphone) including the app 124 is linked or connected to (paired with) the valve control unit 130. This link may be formed, for example, by creating a Bluetooth pairing between the smart device 120 and the valve control unit 130 or by using any other suitable wireless (or wired) connection. In some cases, a user (administrator) may also enter into the app 124 a model number, a serial number, or any other identifier provided on the valve control unit 130. This information may be used by the app 124 to handle the situation in which the app 124 is responsible for controlling multiple shower systems, as described in more detail below.

Operation 220 may also include setting some security, such as a password or key, between the app 124 and the valve control unit 130. This security may be used by the valve control unit 130 to confirm that the app 124 is authorised to modify the settings of the valve control unit 130. In other words, if any future attempt is made to set or reset the valve control unit 130, such an attempt will only be successful if the security is satisfied. For example, the valve control unit 130 may decline any set or reset instructions from the app as unauthorised unless the app 124 is first able to provide the valve control unit 130 with the previously set password or other security information.

In operation 230, the administrator configures the valve control unit 130 to apply (switch on) the functionality that limits the shower duration to a predetermined time as described above, and also to set the value of the shower duration, for example 10 or 12 minutes (for the first phase). In some implementations, setting the value of the shower duration may involve selecting from a dropdown listing of supported values provided by the app. For example, the dropdown listing might offer a predetermined shower duration of 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14 or 15 minutes, and the administrator scrolls through these values to select a particular desired duration. In other implementations, the value of the predetermined shower duration may be fixed for the system and cannot be adjusted using the app 124.

Based on the above, the user of the app 124 represents in effect the administrator or manager of the shower system 100. The administrator configures the shower system 100, and in particular the valve control unit 130, following the procedure shown in Figure 2 (or in any other suitable manner). The settings selected by the administrator, e.g. to activate the effective limitation on shower duration and to specify a time value for this shower duration, can be considered as data 126 maintained at least initially within the app 124. The settings data might also include other preferences, such as the choice of units (litres/gallons, Celsius or Fahrenheit). This settings data 126 is then transmitted from the app 124 on the smart device 120 to the valve control unit 130, for example by using a Bluetooth link established via the pairing procedure of operation 220, or via any other suitable data communications link.

The data 126 representing the settings entered by the administrator into the app 124 and transmitted to the valve control unit 130 is maintained within the valve control unit 130. These settings are then applied to future uses of the shower system 100, and in particular to the way in which the valve control unit 130 controls the actuator 135 and hence the setting of the valve 140. The setting of the valve 140 controls the transmission of hot water to the shower unit 150 and the resulting operation of the shower unit 150.

It will be appreciated that at a subsequent time, the administrator may want to modify or reset one or more of the previously entered settings for the shower control system 100 (and in particular, the settings as held within the valve control unit 130). For example, at a subsequent time, the administrator may change a setting so that the valve control unit 130 is deactivated with respect to valve 140. In this case, the shower unit 150 then operates generally in the manner of a conventional shower, in which the hot water is provided from the hot water supply 112 on an ongoing basis (unless or until the available hot water becomes exhausted). In other cases, the administrator may alter a setting previously supplied by the app 124 to the valve control unit 130 and stored therein, such as to specify the length of time for the predetermined shower duration (the first phase).

Figures 3A and 3B provide high-level schematic diagrams showing an example of the operation of a valve 140 in the shower system of Figure 1. In particular, Figure 3A shows a situation in which the valve 140 is in the open position and Figure 3B shows a situation in which the valve 140 is in the closed position. For the avoidance of doubt, Figures 3A and 3B are the same as one another, except in relation to the positioning of the valve 140 (and associated actuator 135). Accordingly, Figure 3B does not repeat the labelling of Figure 3A to provide greater clarity.

As shown in Figures 3A and 3B, the hot water supply 112 feeds hot water along the hot water pipe 114 towards the valve 140 and the shower unit 150, while the cold water supply 110 feeds cold water along the branch pipe 111 , again towards the valve 140 and the shower unit 150 (see also Figure 1). The hot water pipe 114, which continues from the valve 140 to the hot water feed 152, accommodates a flow detector 118 which is used to detect whether or not there is a flow of water along the pipe 114 towards the shower unit 150. The flow detector 118 is located between the valve 140 and the hot water feed 152 so that it detects both flow from the hot water supply 112 and flow from the branch pipe 111. Note that the flow detector 118 is shown in Figure 3A as being located immediately downstream of the valve 140, which may be convenient for example for installing the flow detector 118 in conjunction with the valve 140. However, in other implementations, the flow detector 118 may be located elsewhere, for example, adjacent to the hot water feed 152.

In operation, if the flow detector 118 detects a flow of water, this indicates that a shower is in progress, whereas if the flow detector 118 does not detect such a flow of water, this indicates that a shower is not in progress. In the present context, the primary interest in the use of flow detector 118 is to detect the start of a flow, namely a transition from no detected flow to a detected flow, and the end of a flow, namely a transition from a detected flow to no detected flow. The start of a flow corresponds to the start of a shower, the end of a flow corresponds to the end of the shower. A user is able to start or end a shower using a control provided in the show unit 150. Such a control is conventional and is generally provided in shower units for turning a shower on or off (irrespective of whether such shower units implement the approach described herein).

In the example of Figures 3A and 3B, the flow detector has a fan arrangement, whereby a flow of water along the hot water pipe 114 causes the fan to rotate about an axis which is aligned with the flow direction. Conversely, in the absence of such a flow, the fan remains generally stationary. This rotation of the flow detector 118 can be detected mechanically, optically, electronically, or in any other desired fashion. It will be appreciated that any other suitable form of flow detector could be used in the implementation of Figures 3A and 3B - e.g. based on imaging the flow, measuring pressure within the flow, detecting noise or vibration caused by the flow, a Hall effect flow sensor, and so on. As shown in Figures 3A and 3B, the shower system 100 includes electrical leads 134, and the flow detector 118 is connected by one of these electrical leads 134 to the valve control unit 130. As described in more detail below, this electrical lead (wire) may allow the flow detector 118 to indicate to the valve control unit 130 when the flow of water through the hot water pipe 114 begins or ends.

Figures 3A and 3B further show a stepper motor 132 which is generally part of the valve control unit 130 (see Figure 1). The stepper motor 132 controls the actuator 135 to move the valve between an open position (such as shown in Figure 3A), and a closed position (such as shown in Figure 3B). The stepper motor 132 is supplied with electrical power over another one of the leads 134. In the situation shown in Figure 3A, the stepper motor 132 has largely retracted the valve 140 from the hot water pipe 114 to allow hot water from the hot water supply 112 to flow relatively freely through the valve 140. At the same time, Figure 3A shows the valve 140 blocking the branch pipe

111 to prevent cold water passing through the valve 140. In the situation shown in Figure 3B, the stepper motor 132 has inserted the valve 140 much further into the hot water pipe 114, thereby constraining (or in some implementations preventing) the flow of hot water from the hot water supply

112 through the valve. In Figure 3B, the stepper motor 132 has also been used to control the valve

140 so as to remove the block on the branch pipe 111. Accordingly, in Figure 3B cold water from the branch pipe is now able to flow through the valve to compensate for the reduction in hot water flow through the valve 140, so that the total flow rate through the valve remains approximately constant.

Note that as described herein, the closed position valve generally denotes the positioning of the actuator 135 and valve 140 that allows the least water from the hot water supply to flow along the hot water pipe 114. However, even in the closed position, the valve might not shut off this flow of hot water completely, i.e. there may not be complete closure with respect to the hot water supply 112, for example, maybe up to 2%, 5%, 10% or 25% of the maximum hot water flow may remain. Conversely, the open position generally represents the positioning of the actuator and valve 140 that allows the most water from the hot water supply 112 to flow along the hot water pipe 114 through the valve 140, but again this may not involve complete closure of the cold water supply via pipe 111 , for example, maybe up to 2%, 5%, 10% or 25% of the maximum cold water flow may remain. Locations of the actuator 135 and valve 140 between the open position and closed position, i.e. intermediate the two locations depicted in Figures 3A and 3B, are generally referred to herein as partly open (or intermediate) positions. It will be appreciated that since the shower unit 150 already includes a control for switching the flow of water through the shower on and off, the valve 140 does not have to replicate this functionality. Rather, the valve is able to open or close to increase or decrease the flow of hot water through the valve (and vice versa for the flow of cold water through the valve), but potentially without the valve 140 ever completely shutting down the flow of hot or cold water. This may help to increase tolerances in the production of the shower system 100, which in turn may reduce cost.

In general terms, the open position of the valve 140 typically corresponds to the valve position that represents a set maximum travel of the valve in the opening direction to provide the maximum flow of hot water (and conversely the minimum flow of cold water) through the valve. The closed position of the valve 140 typically corresponds to the valve position that represents a set maximum travel of the valve in the closing direction to provide the minimum flow of hot water (and conversely the maximum flow of cold water) through the valve. In some implementations, the set maximum travel in the open and/or closed directions may be configured at installation time (rather than necessarily representing the absolute maximum travel supported by the valve hardware), typically depending on the general plumbing configuration which is to receive the shower system 100. For example, in some systems, the open position may represent the valve position which provides the desired flow level of hot water for users of the shower system 150 (even though the valve 140 may in fact be able to open further). This valve position can then be set as part of the installation of the shower system 150 and configured into the valve control unit 130 - e.g. by using smart device 120. A similar approach may also be adopted for setting the closed position of the valve. These settings may subsequently be modified or reset, for example by using smart device 120.

As described above, the valve 140 is used to control both the flow of hot water through the valve from the hot water supply 112 and also the flow of cold water through the valve from the branch pipe 111 to provide an approximately constant output flow. Figures 3A and 3B illustrate two components of the valve 140 - the first component using actuator 135 to control the flow of hot water through the valve from the hot water supply 112, and the second component using a stop or block at the end of branch pipe 111 (where this pipe connects to the valve 140). In the open state of Figure 3A, the first valve component is largely withdrawn from the hot water pipe to allow hot water from the hot water supply 112 to flow through the valve, and the second valve component has the stop present to prevent cold water flowing into the valve from the branch pipe 111. Conversely, in the closed state of Figure 3B, the first valve component is largely inserted into the hot water pipe 114 to restrict or prevent hot water from the hot water supply 112 flowing through the valve 140, and the second valve component has the stop removed to allow cold water to flow into and through the valve 140 from the branch pipe 111. The implementation of valve 140 shown in Figures 3A and 3B is schematic; further discussion potential implementations is provided below.

The valve control unit 130 causes the valve 140 to remain open (substantially in the position shown in Figure 3A) during the first phase of a shower to allow a full flow of hot water from the hot water supply 112 through to the shower unit 150. Once the predetermined shower duration has been reached, i.e. at the end of the first phase, the valve control unit 130 causes the stepper motor 132 and actuator 135 to gradually close the valve during the second phase to the position shown in Figure 3B, in which the flow of hot water through the hot water pipe 114 to the shower unit 150 is greatly reduced (and potentially stopped altogether), being replaced by a compensating flow of cold water from branch pipe 111 which then flows through the valve 140 to the hot feed 152.

As described above, the transition from the open position of the valve 140 to the closed position of the valve 140 is gradual (rather than being a single step function from open to closed). This gradual transition in valve position also produces a gradual fall in the water temperature, so that a user is given a reasonable opportunity to complete their shower, including any desired rinsing, prior to losing much, most or all of their hot water. The stepper motor 132 supports this gradual closing of the valve. In some cases, closing the valve may involve a sequence of moderately sized steps of the actuator 135, where the stepper motor 132 pauses briefly between each step. In other cases, the stepper motor 132 may use a smaller step size, but with a larger number of steps within the overall transition, thereby giving more of an impression of continuous gradual movement of the stepper motor 132 and valve 140. In general, it will be appreciated that the stepper motor may use any appropriate step size during the second phase. Likewise, it will be appreciated that the gradual fall in the water temperature could be implemented in any suitable manner (rather than necessarily using the step motor 132 and/or valve 140 as shown in Figure 1).

In some implementations, the valve control unit 130 is configured so that during the second phase and the transition from the valve being open to the valve being closed, the rate of flow reduction for the hot water from the hot water supply 112 is greater during a first portion of the transition than during a second, subsequent portion of the transition. This may be accomplished, for example, by using larger step sizes for the stepper motor 132 and actuator 135 during the first portion of the transition and smaller step sizes for the stepper motor 132 and actuator 135 during the second portion of the transition.

By way of example, we can write T as the total transition time (i.e. the duration of the second phase). Typically (but without limitation), T is defined to be in the range T1-T2, where T1 may, for example, be any of 10s, 20s, 30s, 1 minute, 2 minutes or 5 minutes, and T2 may, for example, be any of 30s, 1 minute, 2 minutes, 5 minutes, 10 minutes, or 20 minutes (subject to T1<T2). In addition, we can write AF as the total reduction in hot water flow from the hot water supply 112 between the start of the transition (the position shown in Figure 3A corresponding to the start of the second phase) and the end of the transition (the position shown in Figure 3B corresponding to the end of the second phase), Tm as the midpoint of the transition time, AF1 as the hot water flow reduction from the start of the transition time to Tm, and AF2 as the hot water flow reduction from Tm to the end of the transition time (so that AF1+AF2=AF). Having the hot water flow reduction greater during the first portion of the transition than during a second portion of the transition can be expressed as AF1 > AF2. For example, AF1 may represent between 51% and 65% of the total flow reduction (AF) and AF2 may represent the remaining 49% to 35% of the flow reduction; e.g. in some installations, AF1 may be approximately 55% and AF2 may be approximately 45%. One reason for having this steeper reduction in hot water flow at the start of the transition time (second phase) is to ensure that it is noticed by a user. This then provides the user with an appropriate warning of the amount of time to complete their shower before losing some or most (if not all) of the hot water. The implementation shown in Figures 3A and 3B is based on a linear actuator 135, whereby the valve transitions between the open position and the closed position by linear motion into or out from the hot water pipe 114. However, it will be appreciated that many other types of valve are known to the skilled person and might be utilised in the shower system 100 described herein. For example, the valve might be implemented as a flat surface which in a first orientation for the closed position is perpendicular to the flow direction of hot water through the hot water pipe 114. This valve might then be rotated by 90 degrees about an axis corresponding in direction to a diameter of the hot water pipe 114 so that the flow direction of the water now lies in the plane of the flat surface for the open position. In effect, the flat surface now extends in a direction from upstream to downstream and so provides minimal impedance to the hot water flow. Other implementations of the valve 140 will be apparent to the skilled person and are also discussed below.

Figure 4 is a high-level schematic diagram providing an example flowchart for operating the shower system of Figure 1 . In particular, whereas Figure 2 illustrates an example flowchart for configuring the valve control unit 130, Figure 4 illustrates operations performed by the valve control unit 130 after such configuration, namely when users have a shower in the shower system 100.

The processing of Figure 4 commences with detecting the start of flow through the hot water pipe 114 by using the flow detector 118 (operation 410). In some implementations, the flow detector 118 may itself explicitly determine that a start or end of the hot water flow has occurred, and indicate such a circumstance directly to the valve control unit 130. For these implementations, the flow detector may only provide notification to the valve control unit 130 in respect of such transitions (starting or stopping the flow), but without providing any notification during a continuous period without any such transition, i.e. while there continues to be an existing (previously notified) flow, or there continues to be a previously notified absence of a flow. In other implementations, the flow detector may provide the valve input unit 130 with a continuous binary signal indicating that there either is or is not a flow. In these latter cases, the valve control unit 130 is itself responsible for monitoring the binary signal from the flow detector 118 to detect the start or the end of hot water flow within the pipe 114 (as indicated by a transition in the binary signal from the flow detector 118).

In response to the detection of the start of flow at operation 410, the valve control unit starts a timer (operation 420). The duration of the timer corresponds to the value of the predetermined shower duration (first phase) as set by the smart device in operation 230 of Figure 2 (assuming that the valve control unit 130 has been configured to perform the restriction of shower duration as described herein, i.e. that this functionality is switched on). The user then showers as normal, until the timer expires at operation 430. The expiry of the timer causes the valve control unit 130 to enter the second phase, in which the actuator 135 starts to move the valve 140 in the direction of closing the valve, namely from the state of Figure 3A towards the state of Figure 3B. This movement of the actuator 135 leads to a reduction in the hot water flow rate through the hot water pipe (operation 440) to the hot water feed 152. During this reduction in hot water flow, the valve starts to draw in cold water from branch pipe 111 to compensate for the loss of water flow from the hot water supply 112. As a consequence, the overall flow rate arriving at the hot water feed 152 remains approximately constant, however, the temperature of the water arriving at the hot water feed 152 starts to drop, since this flow now contains an increased contribution of cold water from branch pipe 111 (compensating for the loss in hot water from the hot water supply 112). The reduction in flow continues until the valve arrives at the closed position shown in Figure 3B at the end of the second phase. At this point, the shower unit receives little or no hot water from the hot water supply 112 (receiving instead cold water into the hot water feed 152 from the branch pipe 111), and users will generally have chosen to exit the shower.

In the example of Figure 4, the length of the first phase is specified by a duration and the timer is set accordingly. However, in other implementations, the first phase could be controlled by some other physical parameter rather than time. For example, a flow meter may be included to measure the rate (volume) of hot water flowing through the hot pipe 114 from the hot water supply 112. In this case, the first phase may be configured to end once a set amount of hot water has been supplied through from the hot water supply as measured by the flow meter. The set amount of water to flow during the first phase may be specified by the smart device during configuration as per the flowchart of Figure 2 (analogous to setting the duration of a timer). This volume-based approach for determining the end of the first phase may be particularly appropriate when the primary focus is on reducing water and energy use, whereas the time-based approach for determining the end of the first phase may be particularly appropriate when the primary focus is on reducing occupancy of the shower system 100 (although there is clear overlap between the two different approaches).

Similarly, although the length of the second phase is also specified by a time duration in the example of Figure 4, the second phase could be controlled by some other physical parameter rather than time. For example, the hot water pipe 114 downstream of the valve 140 may be provided with a temperature sensor such as a thermocouple or any other suitable form of thermometer, potentially in combination with the flow detector 118 shown in Figure 3A (or in combination with a flow meter as discussed above). One or more of the electrical leads 134 may then be used to report the sensed temperature to the valve control unit 130 (or alternatively a wireless link might be employed). With such a facility, the valve control unit 130 is typically configured to control the valve position based on two parameters, namely (i) time since the start of the second phase (as discussed above with respect to Figure 4) and also (ii) sensed water temperature of the hot water feed 152.

Figure 4A is a schematic diagram showing examples of the variation of water temperature with time for a shower system such as shown in Figure 1 (referred to herein as a temperature-time profile). At the top left of the diagram, there is a horizontal line labelled P1. This represents the concluding portion of the first phase with the valve 140 still in the open position to deliver the maximum amount of hot water. At the end of the first phase, the shower system 100 now progresses into the start of the second phase at time T2s. At this point, Figure 4a depicts two potential profiles to follow: (i) the track (profile) denoted C1 has a straight-line (linear) decrease in temperature with time, while the track denoted C2 is a curved line, in which the rate of decrease in temperature is rapid near the beginning of the second phase (T2s) and has slowed near the end of the second phase (T2f). The profile C2 therefore has AF1 > AF2 (using the nomenclature discussed above). The shapes of possible control tracks are not limited to the profiles of C1 and C2, but may follow other shapes - e.g. the drop in temperature may be relatively rapid at the start and end of the second phase, but more moderate in the middle portion of the second phase.

Although Figure 4A shows two potential tracks C1 and C2, a given valve control unit 130 may support one track or multiple (two or more) tracks. In the latter case, an administrator may be able to select a given curve for the valve control unit to apply in a particular installation. The selected control curve for temperature versus time may for example be specified to (selected on) the smart device 120 and then loaded from the smart device into the valve control unit 130.

It will be appreciated that a user directly experiences water temperature in the shower unit 150. However, the valve control unit does not directly control temperature, but rather controls the actuator position and hence the setting of the valve, and this in turn determines the water temperature supplied to the hot water feed 152 of the shower unit 150. If the temperature is not sensed, then the shower system 100 generally relies upon some advance calibration (at manufacture and/or installation) of the valve control unit 130 and valve 140 to determine how to change the valve setting with time to produce the desired variation in water temperature with time. However, the calibration may not be able to account for all factors - for example, hot water supplied from a solar heating system may vary in temperature during the day.

Providing a temperature sensor to measure the temperature of water entering the hot water feed 152 provides for a feedback process, since the temperature sensor is directly measuring the parameter of interest (water temperature). Thus if a user selects a given profile (path) such as C1 , the valve control unit 130 can use the sensed temperature to determine whether or not the selected path is being properly followed. For example, if the profile C1 is being followed, and a measurement of water temperature is made at a given time corresponding to the point x1 (see Figure 4A), this shows that the measured temperature is below the desired track. This would imply that the rate of closing the valve 140 should be reduced, i.e. the valve should be closed more slowly, to return the temperature to the desired track. Conversely, if the profile C2 is being followed, and a measurement of water temperature is made at a given time corresponding to the point x2, this shows that the measured temperature is above the desired track. This would imply that the rate of closing the valve 140 should be increased, i.e. the valve should be closed more quickly, to return the temperature to the desired track.

Accordingly, such a feedback process based on measuring the water temperature being received by the hot water feed 152 generally results in the valve control unit 130 being able to follow the desired profile (e.g. C1 or C2) more closely than in the absence of such feedback. The use of the feedback process generally makes the control of water temperature more robust in the presence of noise. For example, a residence may use a heat pump and solar heating to produce hot water, but the former may provide hot water with a significantly lower temperature (say 45 ° C) than the latter (say 85 ° C), which in turn may result in some variation in the temperature of water from the hot water supply 112 arriving at the valve 140. The use of a feedback control process for the valve control unit 130 to drive the actuator based on the sensed temperature of the water flowing to the hot water feed 152 may help the valve control unit to follow the desired track (e.g. C1 or C2) for temperature against time even in the presence of some noise (such as some variability in the temperature of the hot water received from the hot water supply 112). The use of such temperature control sensing may also be regarded as a safety feature to help protect against any sudden, undesired rise in hot water temperature through the shower unit 150.

Returning to Figure 4, a normal output of the processing of Figure 4 is that a user switches off the shower following the start of the flow reduction 440, either during the second phase, i.e. between operations 440 and 450, or after the end of the second phase, i.e. after operation 450. In this situation, the valve control input 130 may be configured to maintain the valve 140 in the closed position for a predetermined wait time (corresponding to a third phase), for example between 1 and 10 minutes, or between 1 and 4 minutes. This predetermined wait time might typically be initiated from (i) the end of the second phase or from (ii) the detected time at which the user switches off the shower. After the valve 140 has been static for the predetermined wait time, the valve control unit 130 returns the valve to the fully hot, open position (such as by using actuator 135) and the shower system 100 is now ready for returning to the normal operation, for example, to restart the procedure shown in the flowchart of Figure 4.

It will be appreciated that in some cases the shower may be switched on during the predetermined wait time, thereby causing water to flow to the shower unit 150. However, with the valve 140 still in the static closed position, the shower would remain cold until the predetermined wait time has expired. At this point, the valve control unit 130 is now able to return the valve 140 to the hot, open position, and the user is then able to have a warm shower.

The shower system 100 may be supplied (preconfigured) with a predetermined wait time, such as 2 minutes, but this may be configurable by an administrator, such as by using smart device 120. The predetermined wait time may be relatively long if the primary focus is on reducing water and energy use, whereas the predetermined wait time may be relatively short if the primary focus is on allowing multiple people to use the shower system 100 in quick succession. In some implementations, the administrator may have a facility, e.g. using the smart device 120, to return the valve directly from the cool, closed position to the hot, open position. In effect, this facility would override the predetermined wait time, and may again be appropriate where the primary focus is on allowing multiple people to use the shower system 100 in quick succession.

In some cases, a user may turn off the shower while the system is still in the first phase, i.e. between operations 420 and 430 in Figure 4. There are various ways in which the shower system 100 may respond to such an early termination of the shower. For example, one possibility is for the valve control unit 130 to respond to this early termination by advancing directly to operation 430 (in effect, ignoring any remaining time on the timer), and then following the processing described above. In particular, the valve 140 may be cool or closed during the second phase and a predetermined wait time applied before the valve is reopened to the hot, open position

Another possible response to early termination of the shower is to suspend the timer for a set duration (say one or two minutes). If the shower is re-started while the timer is still suspended, the timer restarts from the value it had when suspended, and processing is then able to continue in normal fashion as described above and as shown in Figure 4. However, if the shower is not restarted while the timer is still suspended, then the valve control unit 130 may respond to this early termination by advancing directly to operation 430 (in effect, ignoring any remaining time on the timer), and follow the processing described above based on having a predetermined wait time. Note that in some cases, the behaviour in response to an early termination of the shower (e.g. whether to advance directly to the second phase, or whether to suspend the timer for a predetermined period as specified above) may be configured by an administrator using the smart device 120.

Accordingly, an approach described herein includes a first phase and a second phase. At the start of the second phase, the shower system (unit, etc) is controlled to start a reduction in temperature of the shower water. In other words, the start of the reduction in the shower water temperature can be considered as demarcating the transition from the first phase to the second phase. The reduction in shower water temperature at the start of the second phase is not a sudden or abrupt drop in water temperature, but rather the start of a gradual decrease in the shower water temperature which is spread out over a prolonged period encompassed by the second phase. In other words, the shower water temperature may be continuously reduced on an ongoing basis over this prolonged period of the second phase. This prolonged period may (for example) be at least 10 seconds in length, and may be longer, such as at least 20 seconds, at least 30 seconds, at least 1 minute, at least 2 minutes, at least 5 minutes or at least 10 minutes (or any value or range therebetween).

In contrast to a sudden drop (step down) in shower water temperature, which may be an unpleasant experience for a user, and possibly also a shock, the gradual decrease in the shower water temperature which is spread over the prolonged period mentioned above provides the user with a gentler notification that the shower control unit has transitioned to the second phase. In addition, a user may be able to estimate the time remaining for the shower based on the rate of temperature change in the water coming through the shower head. For example, if the cooling is relatively rapid, this may indicate that the remaining duration for operating the shower is relatively short. These aspects help a user to manage his or her time in the shower based on the understanding that there is only a limited duration remaining for the shower.

Although the above description has related primarily to a single shower system 100, many homes include two or more showers. Accordingly, the app 124 on the smart device 120 may support the operation of multiple showers as described herein. Table 1 below shows an example of current configuration settings for a house having 3 showers, one located in a family bathroom, one in an ensuite, and one on the ground floor, as specified in the first column of Figure 1 . During the configuration procedure described above with respect to Figure 2, the administrator may enter these names and link them to the appropriate physical devices (shower systems 100) based for example on model and serial number.

Table 1 The second column in Table 1 shows that time control for a shower such as described herein is currently active (switched on) for the showers in the family bathroom and on the ground floor, but not for the en-suite shower. The duration for a shower in the family bathroom has been set to 8 minutes, and the duration for a shower in the ground floor shower has been set to 12 minutes.

The final column in Table 1 provides a link to additional functionality and/or information. For example, this link may be used to select a profile of temperature against time, such as shown in Figure 4A. Another possibility is that selecting such a link might be used to set and/or manually override the predetermined wait time at the end of the shower before the shower system 100 becomes operational (with hot water) for another shower. The link might also be used to access usage data maintained by the smart device app 124, such as the number of showers taken for each shower system over a given time period (say the last month) and/or the estimated consumption of water in such showers. The link might also be used to access data relating to the shower itself, such as model number and manufacturer.

Figure 5 is a high-level schematic diagram providing an example implementation of a valve control unit 130 for use in a shower system as disclosed herein. Although the valve control unit is shown in Figure 5 as a single device or system, it may be implemented as a set of one or more devices, interlinked as appropriate to provide the desired functionality. The power supply for the valve control unit 130 may typically be based on mains 240 or 120 Volts transformed to e.g. 12 DC volts or 24 DC volts depending on the stepper motor 132 or other form of actuator 135 being used (such power may be provided to the stepper motor over the lead 134 shown in Figures 3A and 3B).

The valve control unit 130 includes various software programs 324 which run on controller 362 which may be implemented using one or more processors that execute the software programs 324. The valve control unit stores and uses data 326 which may include, for example, configuration data such as installed at manufacture and/or data provided or updated by smart device 120, such as illustrated in the procedure shown in Figure 2 above. For example, the default duration of the first phase might be set at 10 minutes during manufacture, but a user (administrator) may be able to adjust this setting as desired. The data 326 may also include operational data, such as received from a flow detector 118, which is then utilised by the software programs for determining further operation of the valve control unit 130.

Figure 5 also shows the valve control unit 130 as including a user interface 322. This interface may be used for entering control instructions and/or data into the valve control unit 130, either as an alternative or in addition to using the smart device 120 for this purpose. In other implementations, the user interface 322 may be omitted in favour of using the smart device as the only facility for exchanging user input/output with the valve control unit 130. In some cases, user interface 322 might be used to identify a particular user to the valve control unit 130, and the valve control unit might be configured to personalise the settings applied to the shower system 100 based on the user identity.

The valve control unit 130 further includes a timer 361 which may be used as described above for determining the duration and ending of the first phase and also (if so desired) the duration and ending of the second phase. The timer 361 may also be used to follow the desired temperature versus time profile (such as shown in Figure 4A). Note that this timer 361 may be provided as separate hardware, or may be implemented as a software component by a program 324 running on the controller 362.

The valve control unit 130 further contains a drive or actuator, such as stepper motor 132 shown in Figures 3A and 3B, to operate the valve 140, and a communications interface 328 supporting one or more forms of data connectivity. For example, the flow detector 118 might be connected to the communications interface via a wired USB link (e.g. corresponding to electrical lead 134 in Figure 3A), or by a wireless communications link such as Bluetooth. As described above, a smart device 120 may also use the communications interface 328 to support wired and/or wireless communications between the valve control unit 130 and the smart device 120 for allowing smart device 120 to configure the valve control unit 130 as desired.

In some cases, operational data about the shower, such as the settings of the valve control unit, may be transmitted back to the cloud server, either directly from the valve control unit 130 (using, for example, a suitable Internet connection) and/or via the smart device 120. The communicated information may be provided by way of backup for the settings of valve control unit. In addition, this feedback may be analysed and pooled from multiple different users of many different systems to give practical insight into the use of the device, which may support various activities, such as helping to guide further development of the offering, personalisation and apps.

Figures 6A, 6B, 6C and 6D are high-level schematic diagrams providing an example of a valve for use in a shower system as disclosed herein, including the operation of such a valve. In particular, Figures 6A and 6B are sections through a pipe 610 having a valve positioned within the pipe. In Figure 6A, the valve is shown in the open position so that there is water flow both upstream and downstream of the valve (as indicated by the arrows marked U and D). However, in Figure 6B, the valve is in the closed position, which in effect shuts off or removes the downstream flow.

The valve may be implemented as ball 612 which is large enough to block the entire crosssection of the pipe 610, so that no water is able to flow around the ball 612. The ball 612 is provided with a hollow bore 614 that extends through the centre of the ball. The valve is provided with an actuator 135A which extends out from the pipe (via a sealed opening). The actuator 135A is a rotary actuator in that it is used to rotate the ball 612 between the open position of Figure 6A and the closed position of Figure 6B. In the open position of Figure 6A, the bore 614 is parallel to the flow direction through the pipe 610, extending from the upstream portion of the pipe to the downstream portion of the pipe. This then allows water upstream of the ball 612 to flow through the bore 614 and into the downstream section of the pipe 610. In contrast, for the closed position of Figure 6B, the bore 614 is now transverse to the flow direction. In this orientation, the bore 614 no longer provides a flow path from the upstream section of the pipe to the downstream section of the pipe 610.

In some implementations of the shower system 100 disclosed herein, the valve 140 may comprise two (separate) valve units (components), a first valve unit for controlling the flow of water from the hot water supply 112 via the hot water pipe 114, and the second valve unit for controlling the flow of water from the cold water supply 110 via the branch pipe 111. Each of the two valve units may be implemented, for example, as per the configuration shown in Figures 6A and 6B. The valve control unit 130 is then responsible for ensuring that the two valve units of valve 140 operation in proper synchronism with one another. In particular, the valve control unit 130 opens the second valve unit to increase the intake of cold water from branch pipe 111 at the same time as it closes the first valve unit to reduce the intake of hot water from the hot water supply 112, thereby maintaining an approximately constant flow of water through the valve 140.

Figure 6C shows another potential implementation of valve 140. The basic operation of this valve matches that shown in Figures 6A and 6B, however, rather than forming valve 140 from two separate valve units, the valve 140 is provided as a single device. In particular, the valve 140 of Figure 6C is a four-port device, having two inputs and two outputs. The first input is to receive hot water from the hot water pipe 114, while the second input is to receive cold water from the branch pipe 111. The two outputs are short branches of pipe 114A, 114B which are then combined to provide a single output flow to the hot water feed 152.

As described above with reference to Figures 6A and 6B, the valve 140 of Figure 6C comprises a ball 612 with a central bore 614. The ball can be rotated using a rotary actuator (not shown) between two positions (corresponding to the ends of the double-headed arrow in Figure 6C). In the first position (as illustrated in Figure 6C), the ball 612 cuts off the hot water supply 112 from the hot water pipe 114, but instead the bore 614 allows cold water from branch pipe 111 to flow through the valve to provide the output via pipe section 114B to the hot water feed 152. In the second position (not illustrated in Figure 6C), the ball 612 is rotated in position so as to cut off the cold water from the branch pipe 111 , but to allow hot water from the hot water pipe 111 to flow through the valve and pipe section 114A to provide the output to the hot water feed 152.

The valve 140 also supports intermediate positioning of the ball 612, for example with the bore at an angle of 45 degrees (in effect, midway between the first and second positions described above). In such an intermediate position, the bore 614 is partly connected to both inputs, namely branch pipe 111 and hot water pipe 114. This partial connectivity is supported by providing a flared opening 616 for the bore 614, which ensures that as the flow from one input starts to close with rotation of the ball 612, the flow from the other input starts to open, thereby supporting the provision of an approximately constant flow of water to the hot water feed 152.

Figure 6D shows another possible implementation of the valve 140. The valve comprises a housing 690 including top and bottom surfaces 691 , 692 (references to top and bottom are for ease of description, since the valve 140 may be installed at any appropriate orientation). The housing may have a cross-section (in a plane perpendicular to the top-bottom axis) which is circular, but other shapes such as square or rectangular are also feasible.

The housing is provided with a first pipe coupling forming part of the hot water pipe 114. In particular, there is a coupling to pipe 114i representing the input from hot water pipe 114 to the valve 140, and a coupling to pipe 114o representing the output from the valve back to the hot water pipe 114. The housing 690 is further provided with a second pipe coupling 111 i representing the input from the branch pipe 111 for cold water to flow into the valve 114. For convenience of access, the second pipe coupling 11 1 i is offset by 90° from the first pipe coupling 114i, 114o (but other configurations may be adopted). The second pipe coupling also includes an outflow pipe (not shown in Figure 6D) opposite to the branch pipe 111 i; this outflow pipe links up with pipe 114o to provide the combined output from valve 140, i.e. both hot and cold water contributions to the hot water feed 152 of the shower unit 150.

The valve 140 further includes a piston 676. The piston 676 includes two through-bores, 674 and 684, which are perpendicular to one another (matching the 90° offset between the first and second couplings. The through-bore 674 extends in the same direction as hot water pipes 114i and

1140. As discussed in more detail below, the piston 676 is able to move in a vertical direction within the housing 690, as indicated by the double-ended arrow. If the piston 676 is positioned at the appropriate height, then the bore 674 is aligned with the hot water pipes 114i and 114o, allowing water from the hot water supply 112 to flow through the valve (including inlet pipe 114i, bore 674, and outlet pipe 114o) and onto the hot water feed 152 for the shower unit 150. Thus the configuration shown in Figure 6D corresponds to the open position for valve 140.

If the piston 676 is lowered, the bore 674 in effect drops down below the inlet and outlet pipes

1141, 114o. This misalignment prevents hot water from the inlet 114i from flowing through the valve 140 (in particular, through bore 674) to the outlet 114o. Accordingly, in this configuration, the valve 140 is in the closed position. Note that in this closed position, the cold water input 111 i from the branch pipe is now aligned with the through-bore 684. In this configuration therefore, the cold water from branch pipe 111 is able to flow through valve 140 (including the branch pipe 111 i and through- bore 684). This is in contrast with the situation shown in Figure 6D, in which the through-bore 684 is not aligned with the inflow pipe 111 i, so that the body of the piston 676 effectively blocks or prevents cold water inflow from pipe 111 i from passing through the valve 140. It will be appreciated that the valve may also be set with the piston 676 at an intermediate position, between the open and closed positions, in which case a limited amount of both hot and cold water will generally flow through the valve 140 and onto the hot water shower feed 152.

Figure 6D further shows a screw 630 or other form of shaft which has a head 638 and an outwardly directed thread 635. The piston includes an internal bore or hole corresponding to the size and shape of the screw 630. This internal bore of the piston includes an inwardly directed thread 675 to receive the outwardly directed thread 635 of the screw 630. The screw head 638 is held in a cage 640 which may be made, for example, from polytetrafluoroethylene (PTFE). The cage typically has a toroidal shape or similar. The screw head 638 is further connected to the actuator 135 in any suitable manner to allow the actuator 135 to rotate the head 638 within the PTFE cage. The lubricant properties of PTFE allow the screw head 638 to rotate within the PTFE cage 640 with relatively little friction, thereby increasing the efficiency and durability of the valve 140. Note that during the rotation of the screw head 638, the screw 630 is unable to translate longitudinally, since it is held in position within the cage 640 and between the actuator 135 and the top surface 691 of the housing. Rotation of the screw (shaft) 630 by the actuator 135 does however cause motion of the piston 676. In particular, clockwise rotation of the screw 630 (as seen from the head 638) will generally push the piston downwards towards the lower surface 692 of the housing, while anti-clockwise rotation of the screw will generally pull the piston upwards towards the upper surface 691 . (It will be appreciated that in Figure 6D, the piston is already in contact with the top surface 691 of the housing 690, so that further anti-clockwise rotation of the screw 630 is not possible from this starting position, but would become possible if the piston were first lowered within the housing 690). This vertical movement of the piston by rotating the screw 630 allows the piston to transition the valve between the open and closed positions as discussed above. One benefit of using a valve 640 such as shown in Figure 6D is that the torque applied to rotate the screw 630 can be kept relatively low (this does reduce the speed of operating the valve, but the shower system 100 generally does not require very rapid opening or closing of the valve 140).

Note that if the housing has a circular cross-section, it is possible for the piston 676 to rotate with the screw 630. In this case, rotation of the screw 630 does not generate any up or down (linear) movement of the piston to open or close the valve 140. One way to avoid this issue is for the housing 690 and piston 676 to have a square cross-section, or any other shape that lacks rotational symmetry, since in this case, the piston 676 is unable to rotate within the housing 690, rather the housing walls generally maintain the piston at a fixed angle (azimuth). Accordingly, for such a non-circular crosssection of the housing 690, rotation of the screw 630 is translated as desired into up/down (linear) motion of the piston 676.

There are also various ways for such a up/down linear motion of the piston 676 to be achieved even with a substantially circular cross-section of the housing 690 and piston 676. For example, the outer surface of the piston 676 may be provided with at least one groove extending in a downwards direction, and the housing is provided with at least one corresponding fin also extending in a downwards direction to engage a respective groove. The at least one pairing of groove and fin breaks the rotational symmetry and prevents the piston 676 from rotating within the housing 690. Accordingly, when the actuator 135 rotates the screw thread 635, this motion is necessarily translated into up/down linear motion of the piston 676 within the housing 690, thereby allowing the valve 140 to be opened and closed as desired.

It will be appreciated that the implementations of valve 140 shown in Figures 6A-6D are provided only by way of example, and the skilled person will be aware of many other valve implementations to support the operation of the shower system 100 as described herein.

The approach described herein may be used to operate the shower control device so as to emulate (simulate) the depletion of hot water from the hot water supply as the shower progresses through the second phase. In such circumstances, the user therefore has the impression or sense that they have exhausted the hot water supply. In other implementations, the valve 140 does not shut the hot water down completely, even at the end of the second period, for example because providing only cold water may not be advisable for people who are relatively frail. Figure 3B illustrates an example of a valve 140 which reduces rather than completely cuts off the hot water supply. Retaining some limited flow of hot water through the valve 140 may be especially beneficial in the winter months, when the temperature of the cold water supply may be several degrees below the temperature of the cold water supply in the summer. Accordingly, valve 140 may be configured to maintain a minimal (reduced) hot water supply, for example, such that the water temperature emanating from the shower head does not fall below a given base level. In some implementations, the setting of this given base level temperature may be configurable by a user or administrator, such as by using smart device 120.

In the example shower system 100 of Figure 1 , the shower unit 150 may be conventional. In this context, the valve 140 and associated components (such as actuator 135 and valve control unit 130) may be retro-fitted to work in conjunction with an existing shower system. The operation of valve 140 and associated components may then be managed using smart device 120 as described above to control the flow of hot water to the shower unit 150.

Figure 7, in contrast, is a high-level schematic diagram which provides another example of a shower system 800 as disclosed herein, in which the functionality to control hot water is incorporated into a (modified) shower unit 850. Thus whereas the valve 140 and associated components in Figure 1 may be provided as add-on functionality for an existing (conventional) shower unit 150, in Figure 7 the valve system 840 (generally analogous to valve 140 in Figure 1) is incorporated into the shower unit itself. The shower system 800 of Figure 7 may again be controlled using a smart device 120, which is generally similar in nature and functionality to the smart device 120 shown in the shower system 100 of Figure 1 .

The configuration of shower system 800 in Figure 7 offers certain simplifications compared to the configuration of shower system 100 in Figure 1 , for example, the shower unit 151 may be connected to conventional pipework for hot and cold water supply 112, 110, without involving any additional (new) pipework or pipe interfaces external to the shower unit 850 itself. Accordingly, the configuration of shower system 800 is especially suited to the provision of a new shower, whether a completely new shower installation, or as a replacement of an existing shower unit. In the latter case, the new shower unit 850 will generally able to plumb into the same pipe connections as used by the previous shower.

As shown in Figure 7, the shower system 800 includes a smart device 120, which as mentioned above is directly analogous to smart device 120 such as previously described. The shower system 800 further includes a hot water feed 112 and a cold water feed 110, both of which supply water to the shower unit 850. The output from the shower is controlled by a valve system 840, which in turn is subject to control from a valve control unit 830 (which generally provides analogous functionality to the valve control unit 130 such as illustrated in Figure 5). The output from the shower unit 850 (as controlled by valve system 840) passes through pipe 843 for discharge through shower head 845. Note that the hot and cold water will generally be mixed within the shower unit 850, hence pipe 843 carries just a single flow of water which has a (substantially) similar temperature across the flow. However, in some implementations, the hot water and cold water flows may be kept separate along pipe(s) 843, so that the hot and cold water are only mixed within (or upon discharge from) the shower head 845.

Figure 8 is a high-level schematic diagram depicting in more detail certain aspects of an example shower system 800 of Figure 7. In particular, Figure 8 shows the shower unit 850 including the valve control unit 830 and valve system 840A, which is an example of valve system 840 shown in Figure 7. The valve system 840A comprises two individual valves, namely valve VH 847 for controlling the hot water from pipe 112 and valve VC 848 for controlling the cold water from pipe 110. The valves VH 847 and VC 848 therefore have only a single input each, and likewise a single output each. The respective outputs from VH 847 and VC 848 may be adjusted independently of one another so as to produce a desired aggregate flow rate and water temperature from the shower head 845.

The valves VH 847 and VC 848 do not perform any mixing themselves, rather this is performed by a separate mixer 852 which sits between the valve 840A and the shower head 845. The mixer 852 receives as a first input the hot water output from VH system 847 and as a second input the cold water output from VC 848. The mixer combines these two inputs to produce a single flow which is passed through pipe 843 to the shower head 845. As indicated above, it is also possible for the outputs from VC 848 and VH848 to be supplied to the shower head along separate pipes (instead of the single pipe 843 shown in Figure 8), so that the hot and cold water are only mixed within (or upon discharge from) the shower head 845.

Figure 9 is a high-level schematic diagram depicting another example of the shower system 800 of Figure 7. In particular, Figure 9 shows the shower unit 850 in more detail, including the valve control unit 830 and the valve system 840B, which is another example of valve system 840 shown in Figure 7. The valve system 840B receives both hot water input from hot water pipe 112 and cold water input from cold water pipe 110. The output from the valve 840B travels along pipe 843 and then exits the shower system 800 through the shower head 845 as previously described.

The valve system 840B has a mixing function (analogous to the mixer shown in Figures 3A and 3B for valve 140), in that the valve system 840B is controlled to adjust the temperature of the water output from the valve system 840B by controlling the proportion of hot and cold water in the mixture output from valve 840B. In other words, the proportion of hot water in the output from valve 840B may be increased relative to the proportion of cold water in the output from valve 840B to increase the temperature of the water output from the shower unit 850; conversely, the proportion of hot water may be decreased relative to the proportion of cold water to reduce the temperature of the water output from the shower unit 850.

Accordingly, the valves 840A and 840B of Figures 8 and 9 provide different respective mechanisms for controlling the temperature of water output from shower unit 850. It will be appreciated that valves 840A and 840B of Figures 8 and 9 are provided by way of example, and the skilled person may be aware of other possible implementations of valve 840.

In Figures 7, 8 and 9, the setting of the valve (including valves 840A, 840B) is controlled by the valve control unit 830. For example, the valve control unit 830 may drive one or more actuators (not shown in Figures 7, 8 and 9) to set the valve system 840 according to a desired temperature of the water to be provided to shower head 845. The valve control unit 830 may generally be implemented to provide the same or analogous user functionality as the valve control unit 130 discussed above and such as shown in Figure 5.

One potential difference between shower system 100 and shower system 800 is that in the former, the shower unit 150 generally provides conventional user controls (not shown in Figure 1) for adjusting water temperature (and also in some cases water flow) as per existing showers. During the second phase of operation shown in Figure 4A, the user temperature control provided by such a conventional shower unit may still be operated by a user, but becomes less effective as the valve control unit 130 acts to increase the cold water component of the water supplied to the shower unit 150 on the hot water feed. Accordingly, in the shower system of Figure 1 , the conventional shower controls may utilise a first valve which operates independently of the additional shower controls provided by a second valve, namely valve 140 and valve control unit 130. The effectiveness of the conventional shower controls (first valve) will decrease as the temperature of the (nominally) hot water supplied to the shower unit 150 by the second valve 140 is reduced during the second phase of operation.

In contrast, in the shower system 800 of Figure 7, there may be only a single valve system 840, rather than the pair of valve systems (implicitly) present in the shower system 100 shown in Figure 1 . To avoid potential conflict between how a user of the shower wants to set valve system 840 and how the valve control unit 830 wants to set valve system 840, the user controls for the shower unit 850 may be provided without a direct mechanical coupling to the valve system 840. Rather, operating a user control may generate a signal for the valve control unit 830 (or the valve control unit 830 may sample the setting of the user control on a regular basis). The valve control unit 830 is then responsible for controlling the valve system 840 in accordance with the user temperature setting, unless this is being overridden by the temperature profile set by the administrator of the shower as appropriate.

Although shower system 100 (see Figure 1) and shower system 800 (see Figure 7) have different hardware implementations, the same functionality may be provided to an end user whichever hardware implementation is adopted. In other words, the choice of hardware implementation may be dependent on the installation circumstances, for example, whether a completely new shower is to be provided, an existing shower is to be replaced, or an existing shower is to be retained but augmented by the functionality described herein. Accordingly, user functionality described in relation to one implementation may also be provided on any other implementation (albeit that the low-level implementation of such functionality in terms of valves, actuator, etc will vary across different devices). Thus the user functionality described in relation to shower system 100, see for example Figures 2, 4, 5 and associated description, may generally also be implemented on shower system 800. This includes the ability of both shower system 100 and shower system 800 to be controlled using a smart device, as described above.

Furthermore, the same user functionality may be provided for different types of shower, in the sense of gravity fed, power shower, or electric shower. The first two of these usually have hot and cold water feeds, and hence can be utilised directly for the implementations shown in Figures 1 and 7. Regarding an electric shower, this typically has only a cold water feed, with the incoming water supply then being electrically heated to a desired temperature. The user functionality described above in relation to shower systems 100, 700 controls water temperature in the second phase based on adjusting the relative mix of hot or cold water supplied to a user (the person having a shower). However, analogous user functionality for an electric shower may be performed by managing the electrical heating level applied to the incoming water to control the water temperature supplied to a user in the second phase. Accordingly, a shower system and a method for controlling a shower system are provided herein. The shower system is configured to provide water at a temperature according to user preference during a first phase of the shower. The shower system is further configured to convert from the first phase of the shower to a second phase of the shower in response to a predetermined level of usage of the shower during the first phase. During the second phase of the shower, the shower system is further configured to perform a reduction in the temperature of water supplied from the shower. The reduction is spread over a period of at least 10 seconds within the second phase.

As discussed above, the first phase is intended to provide a user with a reasonable time for having a shower. After the transition to the second phase, the shower system reduces the water temperature in the shower to indicate to the user that the shower is coming to an end and therefore prompts the user to prepare for this, for example by rinsing. The reduction in water temperature in the second phase is generally smooth or gradual to allow the user sufficient time to complete the shower (including rinsing, etc). In some implementations, at the end of the second phase, the valve control system may turn off the water flow through the shower, so that the user in practice has to leave the shower. In other implementations, a user may continue to use the shower after the end of the second phase, however, the lowered temperature remains, so in most cases a user will exit the shower more quickly than if there had been no reduction in water temperature. Various possible approaches for resetting a shower if the user leaves the shower at different stages of the overall procedure have already been discussed above. In some cases, before the shower becomes active again, the valve will operate a cycle from a fully closed state to a fully open state to limit scale build-up.

Figure 10 is a graphical plot showing an example procedure of reducing the water temperature in a shower and focuses on the second phase (Figure 10 does not show the first phase). In this plot, the x-axis is time (in seconds) and the y-axis is temperature (in °C). The solid line along the top shows an assumed hot water supply temperature of 55°C, which is constant across the plot. The solid line along the bottom shows an assumed cold water supply temperature of ambient water of 20°C, which is again constant across the plot. It will be appreciated that the temperature of the hot water is primarily determined by heating settings, while the temperature of the cold water is determined by the time of year (which impacts the mains supply) and whether the cold water is taken directly from the mains, or is temporarily held in a cold water tank (in which case the cold water may warm a little within a building).

Figure 10 further shows a dashed line at 37°C which corresponds to body temperature and is constant across the plot, and also a dashed line at 40°C which corresponds to the shower temperature as set by a user and is again constant across the plot. The last solid line in Figure 10 represents the shower temperature of the water passing through the shower head 845 according to an approach as described herein. This line starts at 43°C, which is the shower water temperature at the end of the first phase/start of the second phase, followed by a decline in temperature over a reduction period of 90 seconds. After these 90 seconds have passed, the water temperature from the shower head is held steady at the final value, which in Figure 10 is 33°C (significantly below the user set temperature of 40°C. The decline during the reduction period is front-loaded, so that the temperature falls by 5°C from 43°C down to 38°C in the first 4 seconds of the reduction period, and then there is a more gradual fall from 38°C to 33°C in the remaining 86 seconds of the reduction period. Having a steep fall at the beginning of the reduction period gives a clear indication to a user that the second phase has started and there is only a limited time remaining within the shower.

It will be appreciated that the numerical values given above with respect to Figure 10, such as the initial and final temperatures of 43°C and 33°C respectively for the shower water, are provided by way of example only, and other implementations may adopt different temperature values. Likewise, the length of the reduction period and/or the profile of the temperature decline with time may also vary according to the circumstances. Note that some or all of these numerical values may be configurable by an administrator according to individual preferences and efficacy as described above.

In some implementations, the temperature level in the second phase may be reduced, but the flow level may be maintained at substantially the same level across the second phase. This can be achieved by changing the relative proportion of hot and cold water in the shower output to reduce the temperature (rather than say just reducing the flow of hot water, which would reduce the temperature level, but also the flow level). Maintaining a given flow level may be desirable, for example to ensure an appropriate supply of water for rinsing.

The shower system may be provided with one or more sensors, such as a flow meter, a thermometer, and so on, to support the user functionality as described herein. For example, in some implementations which include a flow meter, this may be used to detect the start of a shower, and so trigger the first phase. In some implementations, the duration of the first phase might correspond to the overall flow (volume) of water as measured by the flow meter. When the flow volume is measured to have reached some limit (rather having a fixed timing), the shower may now transition to the second phase. This may allow a user to have longer in the shower by using a lower flow rate. This configuration might be of interest if the main focus is on reducing water/heat consumption or cost, but less so if one objective is to help reduce occupation time in a bathroom having the shower.

A temperature sensor might be used at the start of a shower to detect when the water temperature has reached a reasonable temperature, e.g. 35°C. When such a detection is made, this may trigger the start of the first phase (rather than starting the first phase immediately the shower is turned on, but when the water output from the shower may still be too cold to be useful). A temperature sensor may also be helpful to follow the water temperature in the shower during the temperature reduction of the second phase. For example, if a profile has been defined and stored to represent the decrease in temperature with time, the ongoing measurement of water temperature with time provides in effect a closed-loop (feedback) arrangement to follow the desired profile. In particular, if the measured water temperature at a given time within the period of reduction is below the profile, then the rate of temperature reduction should be slowed, whereas if the measured water temperature is above the profile at a given time, then the rate of temperature reduction should be increased.

Figure 11 is a high-level schematic diagram providing an example of a cloud-based shower management system 1100 which also includes a portion referred to herein as the ShowerKap system. The ShowerKap system of Figure 11 may be implemented, for example, based on or using the shower system 100 shown in Figure 1 or the shower system 700 shown in Figure 8. The particular implementation shown in Figure 11 includes a valve 140 (or 840) linked to a cold water supply 110 and to a hold water supply 112, a (ShowerKap) valve control unit 130 (or 830), and a shower head 845 (or shower unit 150). These components may be generally operated in the manner described above, subject to any modification or additional functionality described below.

The valve control unit 130 may be suitably instrumented to measure physical properties such as time (duration), water temperature and/or water flow rate at one or more locations within the overall shower system. These measurements, shown schematically in Figure 11 as Time and Flow, may be used to control the operation of the shower system. For example, as described above, the shower system may be configured to transform from a first phase to a second phase after a predetermined amount of flow (and/or after a predetermined amount of time), wherein the second phase may implement a cooling compared with the hot or warm water supply of the first phase, such as illustrated above with respect to Figures 4A and 10.

A user of the shower is shown as having a smart device 120. In some implementations, the smart device 120 may be used to identify the user to the valve control unit 130, which in turn may apply different control settings to the shower according to the identity of the user (based on their respective smart device 120). An example of such user-specific control settings is given in Table 1 above.

Figure 11 further shows an administrator having for example a smart device 910 and/or a desktop 911. As described above, the settings of the shower system may be configured by such an administrator, for example to apply the specific control settings shown in Table 1 . The administrator may therefore directly control or set the valve control unit 130 and control what various users can or cannot do with their smart device 120 within the overall ShowerKap system. Note that smart device 910 may be the same as or similar to smart device 120, but the functionality available to the administrator is generally greater than the functionality available to a regular user based for example on permissions within their respective apps.

The operations and interactions within the ShowerKap system are not only used for direct control of the output from shower head 845, but some or all of these operations and interactions, including physical measurements such as time and flow, may be recorded. Thus as shown in Figure 11 , details of these operations, interactions and measurements (collectively referred to herein as system operational data), may be transferred to cloud server 912. For example, such a transfer may be performed by the user smart device 120 transmitting the system operational data to the cloud server over the Internet or any other suitable network.

The cloud server 912 may be used to provide a data warehouse storing with system operational data for many different users. The cloud server may utilise one or more processing engines 913 to analyse and exploit the data accumulated into the data warehouse 912. For example, such analysis may involve one or more machine learning (ML) engines - also referred to as artificial intelligence (Al) systems. By way of illustration, the analysis may show that a certain cooling profile is most effective at reducing time and/or hot water consumption within a shower. Furthermore, in some cases, the most effective cooling profile may be personalised to different users, e.g. based on age, shower routine, etc., and/or customised to one or more parameters, such as time of day, weekend or weekday, weather conditions at the time, and so on.

Although the shower systems described above have primarily been intended for domestic situations, the ShowerKap system may be employed in a wider variety of contexts as illustrated in Figure 11 . For example, Figure 11 indicates that a user of the ShowerKap system may be a domestic shower user (as generally described above), an institutional shower user (such as for a prison, the armed forces, a hospital, etc.), or a commercial shower user (such as in a hotel, airport or fitness club). It will be appreciated that the above environments in which shower control such as described herein may be implemented are provided by way of example only, and other environments for performing such shower control may be apparent to the skilled person.

The shower system of Figure 11 is able to provide domestic users, hotels and hospitality, student campus accommodation users, and so on with clear environmental and financial benefits. The success of this approach does not rely solely on water restriction and changing the user's perception that the hot water supply has been exhausted. Rather, this approach may be used in conjunction with behavioural insights and heuristics, acquired and delivered via the app, whereby the entire ShowerKap system acts to influence the behaviour and decision-making of groups or individuals. The system ‘nudges’ users by influencing them to think in new and different ways about water use. Thus even if such users are granted certain operational freedom with respect to the shower system, they may still be encouraged to choose a decision which is better for the environment, economy, and so on. Such influence may be created and supported based on specific usage data (such as system operational data) collected, for example, by valve control unit 130 and/or smart device 120, thereby developing behavioural insights and a range of effective heuristics. These insights and/or heuristics may be personalised in a suite of apps to help encourage greener behaviour including more sustainable water consumption.

In practice, users may be significantly impacted by the behaviour of other people, and this behaviour may form a baseline of what they deem to be acceptable. This means that the more people engage in a given behaviour, the more likely an individual is to agree with such behaviour or believe it to be fair. This insight may be used to encourage greener behaviour, for example by sharing the number of people making small changes in their daily routine to help save water, so that it can be portrayed as a social norm. This will encourage others in turn to follow suit. More powerful variants of this approach may involve personalised messaging, for example mentioning local comparatives for a given user (or from the same peer group), for example based on town, postcode (ZIP code) and so on.

In addition, if something is framed as part of a competition, at least certain users may feel motivated to try harder. An example of this would be where a local water company or institution uses the app to show maps with water usage so that users can easily compare how much water they consume in relation to others. Users may then be rewarded for attaining certain reductions in water consumption, heating consumption, and so on.

Furthermore, detailed behavioural insights may be used to inform the development of personalised messages and incentives incorporated into the app messaging, so that such engagement is best able to motivate users in different groups to reduce their consumption. This approach may help to promote water conservation via social incentives and appeals to the public good, for example by notifying users about how much money they will save through cutting their water use, or how much it will cost if they do not. The approach may exploit cognitive saliency, which is a measure of how easily accessible given information is in the brain of a user. Information with a high cognitive saliency is more likely to influence thinking and behaviour. Accordingly, increasing the cognitive saliency regarding water and energy consumption, such as by using app data to visualise the volume of water consumed by a particular customer compared with average use of their peers or neighbours, increases the understanding and motivation of a water user to reduce consumption. In addition, behavioural science studies show rational arguments are particularly effective when applied in conjunction with behavioural ‘nudges’. People may be motivated by such behavioural nudges, and then feel obliged to rationalise their behaviour. Although such behaviour is not purely rational, people may prefer to see it as such. Accordingly, delivering relevant conservation facts and figures via the app relating to individual decisions which have been made concerning water consumption may facilitate the post-rationalisation process. This in turn can further reinforce conservation behaviour such as in relation to water in general, including hot water in particular. Cognitive saliency and rational argument heuristics may be further enhanced by competition and reward by way of vouchers or other incentives as discussed above for reaching specific reduction targets.

A shower control system such shown in Figures 1 , 7 or 11 may be employed in a variety of different contexts and the control or management of the shower system(s) as described above may be managed accordingly. For example, in a domestic (family) situation, the shower itself may be considered a resource. Thus multiple people in a family may want to use the shower before travelling to school, work, etc, in the morning, or likewise in the evening before going out. If family members tend to spend too long in the shower such that other family members have very constrained timings in the shower, this may lead to contention about the length of time for which the shower is occupied by certain people and how this impacts other family members. One particular issue is that younger users (aged say 14-16) tend to take longer showers, typically about twenty minutes, compared with older users (aged say 55 or over) who tend to take much short showers, typically about six minutes, and this imbalance may cause tension.

The shower system 100 of Figure 1 helps to alleviate this situation by restricting the shower duration for each family member. Moreover, with such an approach, time in the shower may be fairly distributed, because the limited timing for shower duration (the first and second phases) may be applied consistently by the valve control unit 130 for all users. Even if there is no contention for use of a shower between different family members, restricting the predetermined shower duration may help a user improve his or her timeliness. For example, if a user has to arrive at school by a given time each weekday, ensuring they do not spend overly long in the shower as part of getting ready for school helps to avoid one possible cause of delay. The shower system 100 of Figure 1 may also be provided for a domestic user who is still generally able to live at home but who suffers to some extent from dementia or a similar cognitive impairment. In a hotel context, the value of water used is significant. No hotel can run without water and water plays a major part of everyday operations. Hotels rely on the availability of water fortheir service delivery. A hotel may use an average of 1 ,500 litres per room per day. which may significantly exceed the usage of a local population in water-scarce destinations. For example, in some locations, tourism may use over eight times more water per person on average than the local population. Showers are the largest source of guest-generated expense for hotels, including water waste and damage. A hotel guest averaging a 10-minute power shower will typically go through 150 litres of water and require 5.76 kWh of energy in order to heat the water. In addition, a hotel guest may become distracted while waiting for the shower to heat-up or use the shower to steam their clothes. In addition, a guest may mistakenly leave a shower running even after they have left the premises. These wasteful practices generally result in significantly increased water usage, inflated utility costs and additional long-term damage to bathroom facilities.

A shower system 100 as described herein, for example as illustrated in Figures 1 , 7 or 11 , may help to alleviate this situation by restricting in practice the shower duration. In addition, the provision of external monitoring and/or alarms with respect to water usage and flow data may help hotel management with direct interventions to mitigate the above issues and so help to reduce overall energy and water consumption. In some implementations, specific usage data gathered from a shower control (e.g. control unit 130 or smart device 120) may be used to provide nudges to help encourage guests towards greener behaviour and sustainable water consumption. For example, in much the same way as maintaining a hotel key card in a given receptacle may be required to utilise electrical facilities such as lighting, the shower system and app may provide a guest with a choice of remaining ‘opted in’ to a restricted predetermined shower duration. Such a choice may be rewarded, for example, with loyalty programme points or some other benefit for monitored reduced energy use and reduced water consumption. Many hotel guests have indicated they would be willing to act as an “eco-customer” and adopt environmentally friendly behaviours in exchange for a discount or some other benefit or compensation.

A shower system 100 as described herein, for example as illustrated in Figures 1 , 7 or 11 , may also be utilised in a campus situation, in which encouraging a rational use of water may be a powerful tool to promote sustainability. Such intervention could offer significant benefits, for example because a study exploring the water consumption habits of more than 8,000 students in university halls of residence revealed students to use as much as 180 litres of water every day. The majority of this usage relates to showering, whereby on average 18-24 year olds were found to spend 11 .5 minutes in the shower compared with 8 minutes for the over thirties. The adoption of shower system control such as described herein (see also Figure 1 , Figure 7 or Figure 11), would help to alleviate this situation by allowing users to opt into a restricted shower duration. In addition, the provision of external monitoring and/or alarms with respect to water usage and flow data may help campus management with direct interventions to mitigate the above issues and so help to reduce overall energy and water consumption.

The adoption of such a shower system on a campus may also involve a campus-specific variant of the app to help encourage behavioural change and reduction in consumption by tapping into intrinsic values of student users and a ‘common good’ value system to encourage everyone on campus to save water for the shared benefit - e.g. reduced cost.

Table 1 above showed a simple example of app settings to control water usage in a domestic situation. Table 2 below shows an analogous example of app settings to help control water use in a more complex setting having a much larger number of users, for example a hotel or student (campus) accommodation. In particular, Table 2 below shows an example of configuration settings for a hotel or student accommodation having a relatively large number of showers - for example (by way of illustration only) 10 showers located on the first floor, 5 showers located in a gym changing area, and 5 showers on the ground floor (as specified in the first column of Table 2). During configuration, an administrator for these showers may link each individual shower to its group (namely the corresponding row in Table 2), for example based on the model and serial number of each shower.

Table 2

The second column in Table 2 shows for each group of showers whether or not the shower time control described herein is active. As shown in Table 2, this control is currently active (switched on) for the showers on the first floor and on the ground floor, but not for the gym showers. The duration for a shower on the first floor has been configured to 4 minutes, and the duration for showers on the ground floor showers has been configured to 8 minutes. (In this context, the duration may correspond to any suitable timing parameter as used for a given implementation, such as the duration of the first phase, or the duration of the first phase plus the cooling period of the second phase).

The final column in Table 2 may be used to provide a link to additional functionality and/or information. For example, this link may be used to select a profile of temperature against time, such as shown in Figure 4A. Another possibility is that selecting such a link might be used to set and/or manually override the predetermined wait time at the end of the shower before the shower system (e.g. 100) becomes operational with hot water for another shower. The link might also be used to access or upload usage data maintained by the smart device app 124, such as the number of showers taken for each shower system over a given time period (say the last month) and/or the estimated or measured consumption of water in such showers. The link might also be used to monitor excess use in which a shower may have been left on or conversely a lack of use, in which a shower has not been used for a set calendar period. The link might also be used to access data relating to the shower itself, such as model number, serial number and/or manufacturer. It will be appreciated that in some implementations, the link may be used for two or more of the above purposes (and/or for any additional purposes as appropriate). Accordingly, the approach described herein may accumulate system operational data for a shower system (or ensemble of such shared systems) and this data may be exploited in a number of different ways. For example, rather than trying to change what the user thinks by coercion, the system operational data may be used to generate heuristics or similar to encourage (nudge) a user to behave in more sustainable way, but while still allowing such a user to own their experience by choosing to save energy or save water. In other words, while a user may still be free (able) to make their own selection of one or more parameters (such as maximum shower duration), the heuristics and nudges point and encourage the user in the direction of enhanced sustainability, so that a user is more likely to choose actions and/or functionality that better support the environment. This can be regarded as a ‘soft’ approach, in which the shower system provides messages and inputs to a user to encourage, but not strictly require, a desired form of behaviour, in contrast to a ‘hard’ approach in which the shower system is configured to enforce certain behaviours (such as by reducing or terminating hot water flow). It will be appreciated that in some implementations, a combination of both ‘soft’ and ‘hard’ techniques may be used to control and/or encourage user behaviour in a desired direction.

Accordingly, various methods and implementations have been described for operating a shower such as to encourage and incentivise limited usage of the shower, thereby helping (inter alia) to save costs, natural resources, and time. Such methods and implementations may include collecting usage data for multiple different shower units or shower systems, the usage data specifying at least one of hot water consumption, overall water consumption, water temperature and power consumption. This usage data may be provided to a remote system, such as a cloud server, and the usage data for the multiple shower systems may then be analysed on the remote system. Such analysis may involve comparing usage data for two or more different users, including analysis (comparisons) by location, by person, by date/time, and/or by any other parameters of interest.

In some implementations, based on the results from the analysis above, the remote server (system) may automatically adjust the operation of individual shower systems as appropriate. Additionally (or alternatively) the results of the analysis may be used to inform and influence user behaviour. In some implementations, the shower or a connected smart device may provide a user with direct information about their usage of the shower. For example, in some implementations, a user who has relatively high temperature showers compared with other users might be offered an incentive to reduce their hot water consumption, such as points under a hotel reward scheme, and/or a donation from a hotel chain to a charity. Accordingly, personalised data about the shower use of an individual or group of individuals may be used as a (soft) way to influence the behaviour and decisionmaking of individuals or groups of individuals, for example based on social norms, nudge initiatives, heuristics and/or gamification. In addition to personalised messaging, for example comparing water consumption by an individual with that of a peer group for that individual, heuristics may be used to influence and engage with users, having regard where appropriate to strategies such as competition and reward, cognitive saliency and rational arguments.

Furthermore, the system operational data collected as described herein in relation to shower usage may be used for a wide range of tasks, including analytics that support specific water management and monitoring, flow use and reminder alarms. In one example, the system operational data may be used to confirm whether or not a particular shower has been utilised within a given calendar period (such as one month). In some contexts, it is generally desirable that a shower does not go unused for too long, for example as part of a regime to help prevent leg ionella . It will be appreciated that the system operational data collected herein may be used to determine whether a particular shower has not been used for a given number of days, in which case the shower might be automatically operated to flush through water (or an alert may be generated for a human to perform such flushing on a manual basis).

Such an approach may be implemented by determining whenever a shower unit has been activated - this may be assessed for example by using a flow meter to monitor the flow through the shower to obtain usage information. When the usage data indicates that the flow through the shower exceeds a set amount, such that all water held within the shower system since the previous usage has been fed through the shower head to be replaced with fresh water, then this is identified as a shower having occurred. The shower system may collect and store the time and date of each detected shower. As long at the shower system is used without overly long gaps, this generally avoids the potential growth of unwanted organisms in the water held within the shower system.

To ensure that the unwanted organisms are kept under control, the shower system may be set with a threshold period such as some number of days. The stored information regarding the time/date for the most recent shower can be monitored and analysed on an ongoing basis to determine whether the most recent shower is older than the threshold period with respect to the current date. For example, if the threshold period is a calendar period such as a week, a check is made to see whether the last shower performed by the shower system is over a week old. If not, no action may be needed; however, if so, the shower system may control the shower to flush through with water (enough water to remove any microorganisms or other impurities) - either by performing the flush through automatically, or by sending an alert to an operator to trigger such a flush. The threshold period may for example be a number of days, such as 5 days, 7 days, 10 days, 14 days, 20 days or 30 days (or any number of days or range therebetween).

In some cases, the shower system may include a control facility provided in a server or cloud system for preventing potential water contamination as above. This control facility may collect and analyse usage information from multiple different shower units, such as might be found in a hotel, hotel chain, university hall (or halls) of residence and so on. The analysis may be used to determine whether each shower (from the multiple different shower units) has been operated for a shower or similar within the threshold period. If this is not the case, i.e. if a shower unit has not been utilised within the past threshold (calendar) period, the control facility might automatically perform a flushing operation of the relevant shower(s) using remote control of the valves on the shower unit as described above (or any other suitable approach). The control facility may also generate an alert if a shower unit has not been used within the past threshold period to trigger the subsequent performance of such flushing, e.g. by a human operator such as cleaning staff.

Figure 12 is a high-level schematic diagram providing another example of a shower system 1200 as disclosed herein and in many respects is similar to the shower system of Figure 1. In particular, Figure 12 shows a hot water input 112 and a cold water input 110. The hot water goes directly to the valve 140, whereas the cold water input 110 is split into two branches, one of which 111 feeds into the valve 140. The valve 140 is provided with an actuator 135 which in turn is controlled by a valve control unit 130. A hot water feed 152 for the shower head or shower unit (not shown in Figure 12) is taken from the valve 140, while a corresponding cold water feed 151 is taken from the other branch of the cold water input 110 (i.e. the branch other than branch 111).

The valve control unit 130 powers the actuator 135 to move between two position limits as illustrated in Figures 12A and 12B. In the first limit position, as shown in Figure 12A, the actuator 135 locates the valve 140 to allow hot water from feed 112 to flow unimpeded through the valve 140. In contrast, in the second limit position as shown in Figure 12B, the actuator 135 has located the valve

140 so that the cold water from branch 111 is able to flow unimpeded through the valve 140, but the valve is closed to flow from the hot water pipe 112.

In the first position of Figure 12A, the shower system 1200 generally acts as a conventional shower, with both hot and cold water available (in effect, as if valve 140 were not present). In contrast, for the second position of Figure 12B, the shower system 1200 generally acts as (emulates) a shower system which has run out of (exhausted) the hot water, in other words, the supply at pipe 112 has become cold.

Figure 12A generally represents the configuration of the shower system 1200 during the first phase, while the second phase occurs as the actuator 135 is gradually moved in a controlled fashion from the position of Figure 12A to the position of Figure 12B. Accordingly, the movement of the actuator 135 is not a sudden step change between Figures 12A and 12B, but rather a gradual transition over the duration of the second phase. During this transition, the actuator is generally intermediate the two limit positions shown in Figures 12A and 12B, such that a mixture of hot water from pipe 112 and cold water from pipe 111 are passed through the valve 140 to provide warm (but not hot) water.

Note that in some implementations, the valve position corresponding to Figure 12B may still allow a certain amount of hot water to pass through, such that the output water is cool or lukewarm, rather than cold. Such a configuration may still be effective for encouraging a user to terminate the shower, but without becoming unpleasant. In some cases, a user may be able to configure the temperature of the water passing through the valve 140 at the end of the second phase using the valve control unit 130.

Figure 12 further shows one or more sensors 141 which may be used, for example, to measure the flow rate of liquid through feed 152 (such as to detect when a shower has started or terminated) and/or the temperature of the water passing through the feed 152. A temperature sensor

141 may be used, for example, to provide feedback to the valve control unit 130 so that the valve control unit 130 can control the actuator 135 to position the valve 140 such that the water fed to the hot water feed 152 follows the desired temperature profile during the second phase - for example, according to the profile such as shown in Figure 4A.

Figure 12 further shows a smart device 120 which may have an app to interoperate with the valve control unit 130. For example, the smart device 120 may be able to send instructions to the valve control unit, such as to specify the duration and temperature profile for the second phase. The smart phone may also receive data from sensor unit(s) 141 , either directly of via the valve control unit 130. This sensor data may be used, for example, for performing real-time control operations on the shower system, such as managing the valve position and hence the water temperature. The sensor data may also be retained to maintain a record of shower usage, which may be subsequently analysed, for example to help encourage users to reduce their water and power consumption (and provide data for quantifying savings in such consumption).

In some implementations, on user operation of a shower, the shower system may send a start signal to initiate local flow sensors (with thermocouples to measure water temperature). The sensors may be located on the hot and cold feeds 151 , 152. A control unit such as smart device 120 and/or the valve control unit 130 may directly measure or calculate the volume of water flowing through the shower system 1200 and start the cycle of the valve control unit 130 for managing the shower (based on the second and third phases). Usage data such as the duration, plus hot and cold volumes, are recorded and used for real-time control of the shower system, as well as being stored for future analysis.

The valve 140 is configured to receive cold water from a cold water supply 110. The shower system is configured to open or close the valve 140 to control the flow of hot water from the hot water supply 112 through the valve 140 to the hot water feed 152 of the shower. The shower system is further configured to maintain an approximately constant flow of water from the valve 140 to the hot water feed 152 by using the cold water received from branch 111 to compensate for any reduction in the flow of hot water from the hot water supply 112 through the valve 140 to the hot water feed 152 of the shower as the valve 140 closes. (Valve 140 of Figure 12 can therefore be considered as a linear version of the rotary valve 140 depicted in Figure 6C).

The shower system also comprises a control system (such as smart device 120 and/or valve control unit 130) which is configured to maintain the valve in an open condition (with respect to the supply of hot water) over the first phase of the shower for a duration set by an authorised user. The control system then transitions the valve 140 over a second phase of the shower by gradually limiting the flow of hot water to reduce the shower delivery temperature, for example by 3-4 degrees C. In some cases, a user may set the temperature fall, as a single value, and the system adopts a temperature profile which is compatible with this temperature reduction over a set period for the second phase. In other cases, a user may also set the duration of the second phase for the temperature fall, and potentially other aspects of the temperature profile. In general terms, reducing the shower temperature in this gradual manner leads to a shower experience which is somewhat less comfortable, simulating that available hot water is running out.

Accordingly, a shower system 1200 as described herein may include a smart device or smart box which collects usage data that may be analysed to design customised user interactions and content. This usage data helps to tailor nudges and heuristics for diverse user groups to encourage sustainable water consumption. As more usage data is collected over time, machine learning algorithms may be used to develop personalised nudge heuristics to steer entire systems towards sustainability. At the same time, powerful tools may be developed to provide support for managers and operators to manage water usage and energy consumption in a detailed and targeted manner. Macro-monitoring and usage data may also provide real-time information to superusers (system managers or administrators) about leaks. Furthermore, such users may be able to track exactly where the water is being used, thereby helping with prediction, smarter decision-making, and the prevention of waterborne diseases.

The approach described herein offers a comprehensive solution for managing water usage and energy consumption in buildings. Flow meter/thermocouples (FMTs) may be installed within a shower system on hot and cold feeds to a bathroom (shower room, etc), thereby allowing for local monitoring, for example with respect to a bath, sink, shower, and/or toilet. Real-time data on water flow and temperature may then be transmitted to a cloud system (server) for monitoring and analysis, enabling identification and management of areas of high water usage.

A valve such as disclosed herein provides additional user control over water usage, allowing for the fine-tuning of duration, volume usage, flow rates and/or temperature settings. The system can be expanded to include multiple point installations of remote FMTs in water feeds throughout a building, enabling detailed system-wide monitoring and control of energy use, water flow, safety, and usage. Overall, a water management system as described herein provides a powerful tool for building managers and operators to manage water usage and energy consumption, reduce waste, lower costs, and promote sustainability.

According to some aspects of the present approach, a shower system has been designed to nudge users towards changing their water usage habits and to encourage sustainable water consumption. A valve 140 may be controlled to gradually reduce the flow of hot water over a preset time period, simulating the sensation of the hot water supply running out. The shower system also supports smart monitoring, which allows users to control the operating parameters of the valve and to track usage data, including: date, time, duration, and water volume used. This data may then be collected (aggregated) and used to design specific user interactions and content, tailored to the behaviours and heuristics of different user groups, to encourage sustainable water consumption. As more and more usage data is collected over time, this will lead to deeper insights into human decision-making and social interactions, and supported the use machine learning to evolve increasingly personalised nudge heuristics that will steer entire systems towards sustainable solutions.

Figure 13 is a high-level schematic diagram providing another example of a cloud-based shower management system 1500 as disclosed herein. Many aspects of the shower management system 1500 are the same as those of the cloud-based shower management system 1100 as shown in Figure 11 ; accordingly, the discussion of Figure 13 will focus primarily on the aspects of the shower management system 1500 that differ from shower management system 1100.

The shower management system 1500 includes (for example) a shower system 1200 as generally described in Figure 12. The shower system 1200 included in cloud-based shower management system 1500 is instrumented with various sensors 1510 to provide physical information about the operation of the shower system 1200. For example, the sensors 1510 may include thermometers or other temperature sensing devices to determine temperature at appropriate locations in the plumbing network, and/or flow meters to determine the water flow rate at appropriate locations in the plumbing network. It will be appreciated that although sensors 1510 are shown as located together in a group, they may be positioned at any suitable location (or locations) within the shower network 1200 at which relevant information ono water temperature and/or water flow rate is desired.

The shower system 1200 shown in Figure 13 is depicted in the wider context of monitoring water usage within a building with respect to devices 191 such as sinks, baths and toilets. Other example of devices which might be monitored in respect of water usage include washing machines, dishwashers, outside taps, and so on. Information on water usage collected from the sensors 1510 by the ShowerKap control system130 and/or associated smart box 131 may be transmitted to a data warehouse which is part of a cloud server 912. The cloud server 912 may also receive information from smart devices 120 relating to users 917A via any suitable route - e.g. by direct communication between the smart devices 120 and the cloud server 912, and/or by routing via the ShowerKap system 130, 131 to the cloud server 912. The cloud server 912 may further receive information from smart device 910 belonging to an administrator (super user) 917B. The super user is able to change settings within at least some portions of the shower management system 1500, for example to change the timings of the first and second phases for different users 917A having a shower (as described above).

Figure 13 further shows a cloud engine 913 performing various processing on the data received into the data warehouse. This processing may include analytics, such as looking at statistics concerning water usage using different showers by different users, and so on. The processing may further include learning, such as machine learning or artificial intelligence (Al). The machine learning may be used to develop an Al model that (for example) predicts the level of water usage in difference contexts for various control settings within the shower system 1200. The processing by cloud engine 913 may further perform personalisation, such as adapting an output from the Al model to reflect the particular circumstances of a given user, for example based on the daily or weekly shower usage of that user.

In order to support the processing of the cloud engine, shower usage is generally tracked at the individual level as discussed above. This is relatively straightforward in a domestic environment, but may be more involved in a communal setting, for example, one having multiple ShowerKap installations (e.g. shower systems 100, 700, 1200) for use by multiple different users 917A. Accordingly, the shower management system 1500 may adopt a range of different methods and devices for associating an individual user with a specific ShowerKap system 130, 131 in such a communal setting. Various facilities for confirming such an association are indicated by box 1505 in Figure 15). For example, this association may be facilitated through the use of a personalised RF ID device, or by using biometric recognition, such as fingerprint or palm scanning. Such devices/methods may be used to uniquely identify and associate users with respective ShowerKap devices 130, 131. This association may be valid for just a single shower, or for multiple showers such as over a given time period. Additionally, the present approach may allow users to connect and link their personal profiles to one or more corresponding ShowerKap devices 130, 131 through a wireless link, such as one providing Bluetooth or Wi-Fi connectivity. A further approach may involve the use of smart cards embedded with unique identifiers, which users can tap or swipe on the ShowerKap device (e.g. the smart box 131) to establish a personalised association between a given user (the card holder) and a ShowerKap device. A further approach may employ QR codes whereby users may (for example) scan the code using their smartphones to initiate a connection between their profile and a ShowerKap device 130, 131. A further approach may involve using individualised PIN codes or passwords which are assigned to respective users 917A, whereby such a code/password may be entered into a user interface device provided as part of the ShowerKap system to link the account for a given user to a respective shower system.

Once a user 917A has been connected to a ShowerKap device 130, 131 and associated account (such as may be maintained on the cloud server 912), variously functionality may be provided to the user, for example by using an app 124. As one example, users 917A may establish a personalised shower schedule. Other interactions between a user and the shower management system 1500 may allow a user to earn rewards and/or engage with other heuristic functionalities.

This functionality may be used (for example) in a normal domestic environment, but provides particular benefits in communal settings, such as university or campus accommodations 1351 , camping sites, gyms, selected commercial premises 1352, and so on. In such circumstances, users 917A can be linked to a designated ShowerKap device 130, 131 or associated account to actively manage and optimise their water consumption. All usage data is securely gathered and transmitted to the data warehouse managed by cloud server 912. Consequently, this approach has the potential to reduce charges for individual users based on their individual water and energy usage patterns. For example, a user might receive a partial rebate on a subscription fee (or rewards vouchers, etc) if their water usage at a communal facility is comparatively low (since this would help to reduce cost for the operator of the communal facility).

In conclusion, while various implementations and examples have been described herein, they are provided by way of illustration, and many potential modifications will be apparent to the skilled person having regard to the specifics of any given implementation, including the combination of elements or features from different implementations and examples (unless clearly unsuitable). Accordingly, the scope of the present case should be determined from the appended claims and their equivalents.