Background

The present invention relates generally to sustainable energy generation and in particular to solar energy and water collection.

Combined solar energy and rainwater collection devices are known in the art. For example, CA 2164989 to Sheuren discloses a transportable outside shower unit; with lighting and solar processing of hot water. The unit comprises a water catchment tank for closed water circulation, and has a fast connection to the domestic water supply system and to alternative water suction equipment by means of a 12V suction and pressure pump. The unit is employable in lakes, rivers and rainwater storage containers.

JP60033452 to Sakagami discloses a device to supply water and energy to a building utilizing rain water and underground water, an independent electric power generator operated by solar heat, and a large size battery. The device comprises a semi-spherical type reflecting roof and a water reserving tank equipped for securing household water, and a water pump and an underground water well which are equipped for supplementing the shortage of rain water. Solar heat is converted into high pressure steam energy by the semi-spherical type reflecting roof and a spherical heat exchanger to generate electric power by a steam turbine generator. A stable supply of electricity may be effected by providing the battery in parallel.

Summary

We have realised that there is a need for combined water collection and power generation devices. We have further realised that it would be advantageous to have an efficient and space saving rainwater collection and power generation device. It is therefore an object of the present invention to seek to provide a device for collecting rainwater and generating power from solar energy. It is a further object to provide such a device which is efficient and compact. It is a yet further object to provide such a device which can use the generated power to heat the collected water. According to the invention, there is provided an apparatus for collecting solar energy and rainwater comprising: at least one panel; at least one solar cell mounted on said panel; at least one ridge around at least a portion of said panel; and at least one rainwater tank; whereby rainwater falling on said panel can be collected in said tank. An advantage of the embodiment of the present invention is that it is efficient and compact in that the same components which collect solar energy also collect rainwater. A further advantage is that the invention is efficient and compact in that water pipes are disposed around the photovoltaic cells to enable collection of both solar heat by the water pipes and solar energy by the photovoltaic cells. A further advantage is that the device protects a damaged roof from rainwater by covering large areas of the roof and collecting and redirecting water falling thereon. A yet further advantage is that the device is adapted so that the generated energy can be used either to heat the collected water or to provide electricity for other appliances. Brief Description of the Drawings

Various embodiments of the invention will now be decided, by way of example only, with reference to the following drawings, in which: Figure 1 shows the panel of an embodiment of the present invention; and

Figure 2 shows an operational flow diagram of an embodiment of the apparatus of the present invention affixed to a building. Detailed Description

In a preferred embodiment of the invention, shown in Figures 1 and 2 wherein like numerals refer to like components, an apparatus for collecting solar energy and rainwater, is disclosed, comprising: at least one panel 100; at least one solar cell 102 mounted on said panel; at least one ridge 104 around at least a portion of said panel; and at least one rainwater tank 105; whereby rainwater falling on said panel can b e collected in said tank.

The panel provides a dual purpose surface - rainwater collection and solar energy collection via the solar cell.

The panel may be any substantially flat, non-porous and weatherproof material, for example polycarbonate or any other suitable material, and may be any size or shape. There may be one panel or more than one panel, which panels may be interconnected. In the case where more than one panel is provided, the panels may be identical or non- identical and may be the same or different sizes, and may comprise different components or arrangements of components. In a most preferred embodiment, there are two panels which are connected via a hinge 109 such that the panels can be angled for maximal rainwater and/or solar energy collection.

The solar cell may be any component for converting solar energy to electrical energy and may be any photovoltaic cell or other such component known in the art. Preferably, the photovoltaic cells are arranged to cover a large area of the panel, and most preferably the panel is entirely covered by a combination of photovoltaic cells and pipes (described below) to maximize solar energy use.

In the most preferred embodiment, the panel comprises a ridge around most of its edges as shown in the Figures. Gaps 107 between the ridges provide water outlets enabling collected water to flow out therefrom and be collected and directed to the tank as described herein. It is envisaged that the panel will be mounted to a roof or otherwise arranged outside where solar energy can be collected. In such a location, the ridges ensure that all, or at least most, rainwater falling on the panel can be collected and directed - via a channel, vessel, pipes, guttering or the like - to the rainwater tank. The ridge may be any shape and may comprise guttering along the bottom, top, or parts thereof of the panel, and further gutters, channels, vessels or other water collecting means may be arranged on or proximate to the panel for collecting water falling on or close to the panel, for example on a roof to which the panel is mounted. The preferred arrangement of ridges and gutters is that shown in Figure 1. An advantage of the arrangement of ridges and gaps shown in Figure 1 is that the gaps act as gutters and thus any rain falling on the panel is directed down through the gutters. The arrangement of the ridges and gutters on all sides of the panel enables the panel to be arranged flat or at any angle, with any side uppermost, and still enable water collection. This is achieved with the minimum of materials, therefore providing an efficient and lightweight design. A water collecting vessel may be arranged beneath the panel for collecting water from the gutters, which vessel may be connected to the rainwater tank or may itself comprise the rainwater tank.

The rainwater tank may be any vessel capable of containing water and may be open or covered. The tank may be disposed below the panel and water may flow from the panel to the tank under the force of gravity, or alternatively the tank may be above the panel and water may be pumped thereto via a pump and connecting pipes and/or channels as known in the art. At least one channel or pipe may be disposed between the ridge or ridges (or guttering or other water collecting means) and the rainwater tank for connecting the ridge to the tank, whereby rainwater falling on said panel can be collected in said tank. Alternatively the tank may be positioned below the panel and the ridges, guttering, or other water collecting means may feed directly into the tank.

The tank may be connected via pipe 120 to the water supply of the building to which it is attached, or any building, or may be connected to a mains water supply, or to any water supply, or may be connected directly to any application requiring water, such as an outdoor tap 124, an irrigation system, a sewage system, a water purification system, etc, for feeding water thereto. Furthermore the tank may be connected to the heat absorbing pipe of the present invention or to the boiler of the present invention, as described below.

The apparatus preferably further comprises at least one pipe 103 connected to and fed by a water supply; wherein at least a portion of said pipe is mounted to said panel whereby water in said portion can be heated by solar energy.

The at least one pipe is any water pipe as known in the art and most preferably is a pipe adapted to absorb heat from solar rays, that is, made from relatively thin, heat conductive material such as a metal, and coated with a heat absorbing surface coating such as a matt black coating, although it may be any pipe with any coating. Preferably at least the portion of the pipe which is mounted on the panel comprises such heat conductive material and heat absorbing coating, although this material and coating may comprise the whole of the pipe. The heat absorbing pipe 103 is preferably arranged around the edges of the solar cell as shown in the Figures, such that substantially all of the flat part of the (or each) panel is covered either by a solar cell or by heat absorbing pipes. This arrangement takes best advantage of the space available on the panel or panels. It will be readily appreciated that the pipes may be arranged in other ways than that shown in the Figures, such that the panel is still substantially covered by a combination of pipes and cells, and any such arrangement would be advantageous. Furthermore, the pipes and cells may be otherwise arranged in any configuration on the panel or panels, under the scope of the invention, whether or not substantially all of the panel or panels are covered. Still further, the apparatus may comprise one or some panels having only cells mounted thereon, and/or one or some panels having only pipes mounted thereon.

The water supply to which the heat absorbing pipe is connected may be an external water supply, for example the mains water supply (not shown in the Figures), or may be provided by the rainwater tank or boiler of the apparatus. In the latter case a pump 1 18 may be provided as known in the art whereby the water supply is provided by the rainwater tank or boiler. Figure 2 shows the preferred arrangement wherein cold or partially warmed water from the boiler is fed via the pump and pipe 126 to the heat absorbing pipe. Alternatively there may be no pump and any connecting means - pipes, gutters, or the like - may be provided to connect the rainwater tank to the pipes and the water may flow under gravity from the tank to the heat absorbing pipes.

Heated water from the heat absorbing pipe or pipes may flow via pipes 122 to a boiler as described below and shown in the Figures. Alternatively the heated water from the heat absorbing pipe may flow to a radiator, a generator, or to any application requiring heated water.

The apparatus preferably further comprises a boiler 106. The boiler may be connected to the rainwater tank directly (via regular pipes or guttering as known in the art) and thus the rainwater tank may feed water to the boiler for heating. Alternatively the heat absorbing pipe or pipes may be connected to the boiler and feed water to the boiler, such that water entering the boiler is pre-heated by solar heat, reducing the energy required by the boiler to heat the water. This is the preferred arrangement and as such is indicated in Figure 2 by pipe 122. The solar cell or cells convert solar energy into electricity, and thereby supplies electricity. The electricity supplied 1 14 may be connected, (for example via pipe 1 12 as shown in Figure 2) to the mains electricity supply (to which it may be sold), or to an independent electricity supply, for example for powering a building to which the apparatus is mounted, or to any appliance where electricity is required.

Furthermore, means may be provided for creating electricity from the heat collected in the heat absorbing pipes, for example via a steam powered generator or any other means known in the art. This means may similarly be connected to the mains electricity supply (to which it may be sold), or to an independent electricity supply, for example for powering a building to which the apparatus is mounted, or to any appliance where electricity is required.

The apparatus may furthermore be supplemented by mains electricity, that is, the electricity provided by the solar cell and/or heated pipes may be supplemented always or only when required, by a connection 1 13 to mains electricity. Additionally, the apparatus may be supplemented by an external water supply, that is, the water provided by the rainwater tank may be supplemented, always or only when required, by a connection to a mains water supply, a reservoir or other water tanks. The apparatus may further comprise a monitor 108 for monitoring and displaying the amount of electricity available, as known in the art. Most preferably the monitor comprises a button for displaying the available electricity only when requested, thereby saving energy. The apparatus may further comprise a battery for storing unused energy as known in the art. The apparatus may further comprise mounting means attached thereto for mounting the panel to a building or other location, which may be a bracket 1 10 or any mounting means known in the art.

In an alternative embodiment, the apparatus comprises a UV purification unit to cause water to be purified by the action of UV radiation. In a further alternative embodiment, the rainwater tank may be arranged to be stored internally of the building, for example in the roof or loft space of the building.