This invention relates to a power grid to which solar photovoltaic systems mounted onboard vehicles or other moveable objects can be connected.

Photovoltaic power from the sun is a source of clean energy which can help reduce our dependence on power from fossil fuels and so reduce carbon emissions.

However solar photovoltaic systems have disadvantages:

The sun is not a continuous power source. Power is produced during daylight hours only, and, unless it can be stored, is not available to meet demand for power during the hours of darkness.

The amount of area required to produce power is large in comparison to other sources of power.

Traditionally solar panels are placed on the roofs of buildings, but installation costs are high and the number of suitable roofs is limited.

Photovoltaic panels could be sited on vehicles and other moveable objects such as freight containers and power could be stored onboard in power storage facilities such as batteries. This would make many more sites available for the production and storage of solar PV power.

This would be of little practical use unless there was a means by which the PV power produced and stored on so many individual vehicles and moveable objects could be harnessed and made available for use in commercial quantities.

To solve this problem the present invention proposes an inventive power grid to which solar photovoltaic systems sited wholly onboard a vehicle or other moveable object can be connected so that power generated or stored by them can be readily transferred and processed so that a significant source of photovoltaic energy would be available in commercial quantities, some of which, by virtue of the power stored by onboard storage facilities such as batteries and by power storage facilities built into the power grid, could be available to meet power needs during the hours of darkness and periods of peak demand. The invention comprises:

1. A power grid to which solar photovoltaic systems wholly contained onboard a vehicle or other moveable object can be connected for the purpose of transferring photovoltaic power generated or stored by them to the grid, (the power grid )

2. Preferably the inventive power grid has at least one power inlet socket or power inlet of any kind whatsoever to enable power to be transferred to it from any solar photovoltaic system, wholly mounted onboard a vehicle or other moving object, connected to it.

3. Preferably the grid will have one or more housings (grid housing) which can be weatherised and can be in a variety of suitable forms, such as, for example, a kerb-side post or pillar, a wall mounted container or any other form of housing for the purpose of housing one or more or a variety of grid components of any kind such as grid power inlets, system controls, power processing devices and equipment, smart recognition touch pads, display panels, cabling etc. Preferably the grid power inlets are sited at places where the power outlets of solar PV systems mounted onboard vehicles or other moveable objects can readily be connected to them.

Preferably the grid contains whatever system controls, devices or equipment as are necessary or desired to process, transform, or convert the electric power supplied to it in any way desired by the operator of the grid, and further, that the grid comprises a network of electric cables to transfer or convey the electric power from the grid power inlets to the system controls and power processing devices and equipment forming part of the grid system and from there to any place where there is an end user or market for the electric power as processed by the grid system.

Preferably the inventive power grid system will have at least one power inlet which is capable of being connected to the power outlet of an onboard PV system by means of a suitable connection cable or by any other means.

Preferably the grid power inlets can take different forms in different embodiments of the inventive system. For example, but not exclusively, they can take the form of a power inlet connector placed in a road surface and designed so that a corresponding power outlet connector mounted on the underside of a vehicle parked over it can make connection and so enable power to be transferred from the onboard PV system to the inventive power grid, or it can take the form of a power inlet connector placed on an overhead gantry so that a corresponding power outlet connector mounted on the roof of on a vehicle can make connection and so enable power to be transferred from the onboard PV system to the inventive power grid. Both examples meaning that power can be transferred to the grid from a vehicle automatically and without the need for a manually fitted connection cable.

Preferably, in some embodiments of the system, the system controller and system devices and power processing equipment will be housed in one location and be connected by cabling to grid power inlets located at other locations. For example, in an urban street, there could be a number of weatherised grid posts each housing one or more grid power inlets, situated beside designated street parking bays, with each grid power inlet connected by cabling to a centralised control unit housing the system controller, user recognition equipment and display, power processing equipment and other grid devices.

Preferably in some embodiments of the inventive system, the housings for the grid power inlets will contain, in addition to the grid power inlets, some or all elements of the system controls, power processing equipment and other system devices. For example they may house a smartcard reader and interaction equipment, performance and information display panels, dc to dc transformers and dc to ac inverters etc.

Preferably the inventive power grid will have a system controller and an arrangement of one or more power inlet sockets to enable the transfer of power from an onboard solar PV array only, a transfer of power from an onboard power storage facility only or a transfer of power from both an onboard solar PV array and power storage facility. Preferably the inventive power grid system will have controls enabling it to set the times when at least some grid power inlets are connected to or disconnected from the rest of the power grid. This will enable the grid system to control, for example, the times when power can be transferred from the power storage facilities of any onboard PV systems connected to the grid power inlets and to call for power to be transferred at times of peak demand or during the hours of darkness.

Preferably in some embodiments of the inventive grid system the housings for the grid power inlets may contain a grid power inlet connector on an extendable and retractable flexible cable for connection to an onboard PV system.

Preferably some embodiments of the inventive grid system will have smart recognition or identification equipment and facilities such as a smartcard reader fitted in grid housings, and associated smartcards, or other means, which can be issued to potential users of the grid, such as owners of vehicles fitted with an onboard PV system, to enable them to connect to and use the grid ; to check the electrical characteristics of the connected onboard PV system in order to ensure it is compatible with the power grid, and if so, to enable connection and transfer of power from it to the grid; to enable the measurement, and any other details desired, of the amount of power transferred from an onboard PV system during the time connected and to credit, to the associated smartcard or by whatever other means desirable, the value of that power to the user, the vehicle owner or person entitled to payment.

Preferably, in some embodiments of the inventive system, the system will have controls and power processing equipment to automatically recognise and enable a range of onboard PV systems with different current and voltage outputs to be connected and transfer power to it.

Preferably in some embodiments the grid will contain controls and equipment to modify or transform or convert the electric power supplied to it into whatever form is required and to transfer that electric power to an end user, or market or electric storage facility or to existing or other electric power distribution networks. Preferably in one embodiment, the grid system can serve, though not an exclusive list of potential uses; vehicles or moveable objects parked in urban streets or roads, bus parking yards, airport or other long stay vehicle parks, railway yards or sidings, vehicle manufacturer's stock yards, shipping or freight container storage yards, boat, barge or yacht moorings or marinas, goods storage yards etc.

Preferably in some embodiments of the inventive power grid, there will be a facility with appropriate system controls whereby one or more power storage batteries or other power storage facilities which have been removed from an onboard PV system can be connected to the grid, and any power stored by them can be transferred to the grid when the grid system controls make a call for the transfer of such stored power. An example of such a facility would be a "battery bank" to which a freight company, operating a fleet of lorries fitted with rapid battery removal and replacement facilities, could connect fully charged batteries removed from lorries coming into after their various journeys, and from which they could take discharged batteries to replace in the lorries, so enabling the lorries to continue on another journey with an empty storage battery.. The battery bank facility would be an integral part of the power grid. The grid would be able to draw off the stored power when required, for example at times of peak demand, or during the hours of darkness.

18. Preferably in some embodiments. The grid will have a power storage facility, such as a battery bank, which can store power transferred to the grid from any solar PV systems connected to it, including power from solar arrays and power storage batteries, and can draw on any power stored in the power storage facility for processing and delivery to a market or customer for power from the grid.

19. Preferably in one embodiment, the inventive grid system can simply be added on as an extension to an existing photovoltaic installation, to connect it to areas nearby where vehicles or moveable objects can be parked.

20. Preferably the inventive power grid system will contain all safety features

necessary and which are known in the art.

Drawings

The invention will now be described solely by way of example and with reference to the accompanying drawings in which:

Figure la and lb show an embodiment of the inventive power grid, suitable for an indoor car park .

Figures 2a, 2b and 2c show an embodiment of the inventive power grid applied to an urban street setting.

Figures 3a and 3b show an embodiment of the inventive power grid applied to buses parked in a bus parking yard or a bus garage.

Figures 4a and 4b show another embodiment of the inventive power grid which can be applied to a car park or an urban street setting.

Detailed description of the drawings

Figure la shows an inventive grid comprising five grid inlet housings 11 connected by low voltage direct current [dc] cabling 14a to a central processing unit 15 which houses the system controller, a dc/ac inverter and ancillary system equipment etc, (for clarity details are not shown). Grid cabling 14b carries high voltage ac power from the central processing unit to the local utility power network.

Five cars 6, each of which have an onboard PV system which includes a solar PV array and a power storage battery, are shown with their PV systems connected to the power grid inlet housings 11 by means of connection leads 8.

Figure lb shows a magnified view of one of the grid power inlet housings 11. This is in the form of a wall mounted box in which is fitted a grid power inlet 9 and a smartcard reader 15d. Cabling 14a connects the grid power inlet to the grid central processing unit 15 [not shown].

A car 6, is shown with an onboard PV system (not shown) connected by connection cable 8 to the grid power inlet 9.

The grid has smartcards 27 to enable users of the grid to connect to it.

This embodiment of the grid is designed for use in indoor parking situations such as a multi-storey car park or a basement car park for residents of a block of apartments.

In operation, the owner of a car fitted with an onboard PV system 6, parks beside a grid housing 1 1 and connects his onboard PV system to the grid power inlet 9. He then swipes his smartcard 27 to the smartcard reader 15d. If recognition is successful the grid activates the connection and low voltage DC power can be transferred from the onboard power storage battery to the central processing unit 15 of the power grid. The power is then converted into suitable high voltage AC power by the dc/ac inverter and transferred by grid cabling 14b to the local utility power grid. The amount of Ac power transferred is recorded by a smart meter.

When the vehicle owner wishes to disconnect from the grid, he again swipes his smartcard 27 on the smartcard reader 15d. The grid measures the amount of power transferred to the grid during the period of connection and credits its value to the smartcard 27 and deactivates the connection. The car owner can then disconnect from the grid.

On leaving the car park, the car will have a discharged power storage battery which can be recharged by its PV array when on the move or parked outdoors in sunlight.

In Figure 2a three streets 18a, 18b, and 18c are shown. The street pavements are fitted with four sets of an embodiment of the inventive grid system. Each set consists of a number of kerbside grid power inlets 9 connected by system cabling 14 to a central unit 15 which contains grid controls, smartcard reader, display panel and processing equipment. High voltage AC cabling connects the central units 15 to the local utility power grid 13.

Cars 6 and 6a are shown parked on the streets. Cars 6 are fitted with an onboard solar PV system and these are connected to the grid power inlets 9 by a temporary connection cable 8.. Cars 6a are not fitted with onboard solar systems and are thus not connected to the grid- Figure 2b shows a panoramic view of the same embodiment of the inventive grid system as shown in figure 2a.

Three grid power inlets 9 are shown housed in weatherised upright kerbside posts 11. These are connected by grid cabling (not shown) to a grid central unit 15. A car 6, with an onboard photovoltaic generating system and power storage batteries (not shown) has its onboard PV system connected by means of a temporary connection cable 8 to one of the grid power inlets 9. Direct current dc power generated by the car's onboard photovoltaic array and from its storage batteries is transferred via the connecting cable 8, the grid power inlet 9 and the grid cabling (not shown)to the central unit 15 where it is converted into high voltage alternating ac current and transferred to the local urban power distribution grid. Figure 2c refers to the same embodiment of the system as shown in figures 2a and 2b and shows a detailed view of the kerbside posts 1 1 and the grid central unit 15 .

Three grid power inlets 9 are shown housed in weatherised upright kerbside posts 11. These are connected by low voltage direct current (dc) cabling 4a to a weatherised grid central unit 15.

The grid central unit 15 houses a dc to ac inverter 15a, which converts the direct current from the grid power inlets 9 to high voltage alternating current (ac) and this is conveyed by high voltage cables 14b to the market or end user, which in this case is the local urban utility power distribution grid 13.

The grid central unit 15 also contains system controls and equipment 15b to monitor and control the performance of the grid; smart controls to identify users of the grid and permit them to connect to the grid; controls to identify and interact with solar PV systems contained onboard vehicles and connected to the grid power inlets 9; controls to measure the amount of power transferred to the grid by PV systems connected to it and to enable the value of that power to be credited to the users of the system;

controls to measure the amount of power supplied by the grid to any end user; safety controls and any other necessary controls. The grid central unit 15 also has other features such as a smartcard reader 15d where system users having an appropriate grid smartcard 27 can sign in to enable connection to the grid, and an interactive display 15c to show details of users, power transferred etc.

In some embodiments, some of the controls, such as the smartcard reader, interactive display panel and sign in systems, can be located at the power inlet housings 11 instead of at a grid central unit 15.

In operation, a person using the system parks his vehicle 6 next to a grid post 11 and connects his onboard PV system to the grid power inlet 9 using a connection cable 8. He signs in to the power grid using his grid smartcard 27 and if all is satisfactory, the grid controller activates the connection.

Power is then transferred from the onboard solar array to the central unit 15. This converts the low voltage dc power to high voltage alternating current (ac) and transfers it to a market destination or end user, which in this case is the local utility power grid 13. The arrows indicate the direction of electric flow.

In the same way, the power stored by the onboard power storage batteries of the car 6 can be transferred to the power grid and onward to the end user 13, but in this case, the times at which the stored power is transferred can be timed, either by the grid controls in the central units 15, or by the control systems onboard the cars 6, so that power can be transferred whenever required, for example, at times of peak demand on the utility power grid.

With reference to Figure 3a of the drawings, this depicts eight buses 16, parked in a bus parking yard or bus garage.

All of the buses have onboard solar photovoltaic systems which includes, but not exclusively, a PV array, power storage batteries with a quick battery removal and replacement facility, and a power outlet, (not shown for clarity)

The solar PV systems onboard the parked buses 16 are connected to grid power inlets 9 by means of removable connection leads 8. Any power produced from the onboard solar systems can be transferred by means of grid cabling 14a to the grid central control unit 15 which converts the incoming dc power to high voltage ac power and exports this via cabling 14b to an end user which in this embodiment is the local utility power grid 13.

This embodiment of the power grid includes a battery bank 17 connected to the central processing unit 15 by means of grid cabling 14a. The battery bank 17 enables batteries which are removed from buses to be connected to the grid.

One bus 16b, is shown having a fully charged battery 3 a removed and placed in the battery bank 17. A discharged battery 3b is shown being removed from the battery bank 17 and being placed in bus 16b in place of the fully charged battery. The bus can thus proceed on its next route and its solar array can charge the replacement discharged battery 3b en route. This quick battery exchange facility reduces the need for vehicles to carry an excessive number and weight of batteries, and can mean that large fleets of lorries or transport vehicles can have a large bank of batteries, where power can be stored, as part of the inventive grid system.

Power stored by the batteries in the battery bank 17 is transferred to the grid central processing unit 15 where it is processed and exported to the utility grid 13 as high voltage ac electric.

The grid control unit 15 can set the times at which power stored in the battery bank 17, or in the power storage batteries onboard the buses 16, can be drawn off, processed by the grid central unit 15 and exported to the local utility 13. This means that stored power can be available to the utility grid when required, including during the hours of darkness.

Figure 3b of the drawings shows a bus 16 having an onboard solar PV system which has among its components, a solar PV array 1; power storage batteries 3 a which have quick removal and replacement facilities, and a power outlet 4.

The onboard PV system of the bus 16 is connected to a grid power inlet 9 by means of a removable connection lead 8. The grid power inlet 9 is built into in a weatherised housing in the form of an upright post 11 and is connected to the remainder of the inventive power grid (not shown) by grid cabling (also not shown).

PV Power from the onboard solar array 1 and the onboard storage batteries 3 a can be transferred to the inventive grid system by means of the connection cable 8 which connects the power outlet 4 on the bus to the grid power inlet 9. The PV power can then be transmitted to the inventive power grid for processing and sale to an end user or market.

Figure 4a shows a power grid which consists of a weatherised housing 11 in the form of an upright kerbside post. The post houses a grid power inlet 9 connected by low voltage DC cabling 14a to the system controller and power processing equipment 15a which includes a dc/ac inverter 15b. High voltage ac cabling 14b connects the power grid controller and processing equipment 15a&b to the end market 13, which in this example, is the local urban utility power grid.

A smartcard reader 15d is located on top of the weatherised housing post 11. The system controller 15a enables the smartcard reader 15d to interact with any smartcards 27 designed for the grid and which are an integral part of the grid.

Two power indicator lights 28 are also located on top of the weatherised housing.

Figure 4b shows two of the weatherised grid housing posts 11 in an urban street setting. A car 6 equipped with an onboard solar PV system is shown parked beside one of the grid posts. The solar PV system onboard the car includes a solar panel array 1 , a power storage battery 3 and a power output 4. For clarity, other components of the onboard PV system are not shown.

In operation, the grid user connects the power outlet 4 of the car PV system to the power inlet 9 of the inventive power grid by means of a connection cable 8.

He places his grid smartcard 27 on the smartcard reader 15d and if recognition is satisfactory, the power grid controller 15a activates the connection and low voltage dc power can flow from the vehicle's solar array 1 and power storage battery 3 via the connecting cable 8 to the grid. The grid inverter 15b converts the low voltage dc power into the appropriate high voltage ac current and this is transferred by grid cabling 14b to the local urban utility power grid 13. One of the indicator lights 28 glows green when a connection is satisfactory and activated. The second indicator light glows green when power is being transferred to the power grid.

When the user wishes to disconnect from the power grid, he again presents his smartcard 27 to the smartcard reader 15d. The power grid controller 15a measures the amount of power transferred to the power grid during the period of connection and credits its value to the smartcard.

The connection is then deactivated and the user can disconnect the connection cable 8.