ES1310948U - SOLAR PARKING - Google Patents

Abstract

A solar parking lot comprising: at least one support structure and a roof supported by the at least one support structure, the roof being arranged to support at least one solar panel, the at least one support structure being formed from a fiber reinforced plastic (FRP) material and comprising an outer shell enclosing an interior volume and at least one hydrogen storage tank located within the interior volume for storing hydrogen fuel for dispensing to a vehicle. (Machine-translation by Google Translate, not legally binding)

Description

DESCRIPTION

Solar parking lot

Field of invention

The invention relates to an improved solar parking lot for the generation and storage of energy for use in a grid-supported, business, domestic and/or electric vehicle charging facility, as well as the storage and distribution of hydrogen fuel for hydrogen-powered vehicles.

Background

Carports are covered structures that provide a roof or canopy, under which one or more vehicles may be parked, thereby providing, to some extent, shelter for the vehicles. It is also known to use the roof of such structures to accommodate solar panels and/or solar modules, for example, to generate electricity and/or heat water and such structures may be designed to accommodate a small number of vehicles, or may cover large parking areas accommodating large numbers of vehicles. Existing solar carports are typically made of steel and have support structures connected to and supporting a roof, to which a photovoltaic (PV) solar panel is attached to generate electricity. Any associated additional components, such as electrical components (e.g. cables, inverters and/or charging connectors) or water drainage equipment, are either fixed to the outside of the solar carport, contained internally, or housed separately in the carport.

There is a need for car parks that can effectively support solar PV panels or solar thermal modules over large spans and that can contribute to the sustainability of existing properties and, in particular, new property developments by meeting the needs for the use of sustainable and renewable materials and the generation and storage of renewable energy.

WO 2019/064010 A1 describes a solar car park comprising hollow support structures.

Summary of the invention

The present invention provides a car park, in particular a solar car park, according to claim 1. In another aspect, the invention provides a car park according to claim 6. The invention provides a car park in which the supporting structure(s) preferably comprises a hollow FRP (fibre reinforced plastic/fibre reinforced polymer) structure in the form of an outer shell which is strong, easy to manufacture and which contains an interior space or interior volume which can advantageously be used to house various different components related to the functionality of the system, as set out below. The interior volume can be used for the storage of hydrogen fuel and/or can be used to contain liquid electrolytes to form a flow battery, in particular for the storage of electrical energy generated by PV solar cells provided on the roof of the car park. In one embodiment, the invention provides a solar carport comprising at least one support structure, wherein the at least one support structure comprises a trunk portion located on a surface and a branch portion coupled to, or integrally formed with, the trunk portion, the trunk portion and the branch portion each having a hollow interior that when coupled together define an interior volume or cavity within the support structure. The support structure may comprise at least one support tray and/or a beam located on the branch portion of the support structure, supporting at least one solar panel for absorbing solar energy. At least one electrical component connected to the at least one solar panel may be located within the interior volume of the support structure. The invention advantageously integrates energy storage, for example in the form of a battery or storage of a fuel such as hydrogen, within at least one support, which shields the components used for such storage from the outside environment and restricts access to the components. Embodiments of the invention also advantageously combine electricity generation, for example in the form of PV solar cells, with energy storage, for example in the form of a flow battery and/or the provision of energy to vehicles, for example in the form of electric vehicle (EV) charging and/or a hydrogen fuel dispenser.

Each support structure may comprise a substantially vertical central trunk portion for ground mounting and a branch portion for supporting the roof. The branch portion comprising at least one laterally extending branch member shaped to provide a substantially flat upper surface for supporting the roof. Preferably, the upper surface provides a substantially flat surface [curved roofs are also needed to be covered in light of the advancement of flexible solar materials and paint] on which a substantially flat roof structure may be supported, which is advantageous for supporting large spans of flat solar cells, for example. However, other forms of roof structure may be supported and the upper surfaces of the support structures may be shaped accordingly. The term "ground" herein may refer to surfaces other than the ground itself, such as an above ground level of a multi-storey car park, for example a rooftop or other platform on which vehicles may be parked and on which the car park is installed. It will be appreciated that the car park may also be used in facilities housing a number of different types of vehicles including, but not limited to, cars, vans, motorcycles, bicycles, scooters and the like and may provide shelter and optionally electrical charging and/or hydrogen refuelling for any such vehicles. Support structures may also be arranged to support a roof structure in other applications, such as over water, for example a reservoir, river, sea or lake, in which case the support structures may be either fixed or floating.

In one embodiment, the branch portion and the trunk portion of the support structure each comprise single piece continuous molded fiber constructions. Alternatively, the entire support structure may comprise a single molded component. This advantageously provides simplicity in assembly and avoids structural vulnerabilities where components would be connected. These constructions may be used to advantageously provide a single continuous volume within the support structure to maximize the interior volume for storage of components such as storage tanks for electrical components, water, gases, and/or battery electrolytes as will be described below. The branch portion may comprise one branch member or two branch members extending laterally in opposite directions. In a preferred embodiment, the branch portion and the trunk portion are each made from a continuous fiber reinforced plastic.

In a preferred embodiment, the branch portion has a variable moment of inertia. This increases the overall strength and achievable spans of the branch portion and also reduces deflection along its length. The roof structure may also have a variable moment of inertia along its length to increase the strength and achievable span of the roof. In some embodiments, the branch portion may be reinforced with carbon fiber, flax fiber, or other high modulus materials to further improve the above parameters.

The roof may comprise a plurality of roof elements each extending in a direction so as to form a span between two spaced apart support members, each roof element arranged parallel to, and connected to, an adjacent roof element. Each roof element may comprise a substantially planar base and side walls extending substantially perpendicularly from the base to a U-shaped cross section, the roof elements (also referred to herein as "trays") being arranged such that the side walls of adjacent roof elements abut each other and are connected to each other along the length of the span. This arrangement has been found to provide rigidity to the roof and enables the roof to achieve long spans (e.g. 15-18 m) between adjacent support structures. At least one roof element, and preferably every other (i.e. staggered) roof element, is provided with a flange extending from a distal edge of at least one side wall and arranged to seat against the distal edge of the side wall of an adjacent roof element. This further increases the rigidity of the roof and may also be used to provide a watertight joint between adjacent roof elements. Roof elements may be formed from materials including, but not limited to, FRP, for example, fiberglass with a core of balsa wood, foam or PET or other lightweight core material. This arrangement has been found to provide a lightweight yet rigid roof structure that is also water resistant.

In some embodiments, the solar panel is a PV solar panel. In a preferred embodiment, the PV solar panel is connected to the power grid through the cavity in the support structure. This synergistically protects the grid connection from the outside environment while preserving the environment of the grid connection.

In some embodiments, the solar panel is a solar thermal panel that provides hot water.

In some embodiments, a battery system may be housed within the cavity of the support structure. In a preferred embodiment, the battery system may comprise a charging point for an EV. In embodiments comprising both PV solar panels and a battery system, power generated by the PV solar panels may be used to charge the battery system. In some embodiments, the trunk portion and/or the branch portion of the support structure may house a flow battery comprising storage tanks for storing cathodic and anodic liquid electrolytes, a pair of electrodes separated by a membrane, and one or more pumps for circulating the electrolytes past the membrane. The electrolyte storage tanks may be housed in, or integrally formed with, the support structure itself or within separate support structures. In other embodiments, the hollow support structures may be used to house cylinders and/or tanks for storing hydrogen, for dispensing to hydrogen-powered vehicles. In the embodiments described below it will be appreciated that the described embodiments which are arranged to store hydrogen may alternatively be used to store other fuels such as, but not limited to, LPG.

Brief description of the drawings

Embodiments of the present invention are now described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 shows a solar parking layout;

Figure 2 shows a cross-sectional view of a tray arrangement for use as the roof structure on a solar car park;

Figure 3 shows a side view of a support structure and a plan view of a footprint of the base of the support structure;

Figure 4 shows, schematically, the interior of a support structure housing hydrogen storage tanks and Figure 4a shows a cross section through line a-a in Figure 4;

Figure 4b shows an alternative configuration of a support structure, schematically showing the interior of the support structure housing the hydrogen storage tanks and Figure 4c shows a cross section through the line a-a in Figure 4b;

Figure 5 shows, schematically, an alternative arrangement of the support structure housing an integral hydrogen storage tank and Figure 5a shows a cross section through the line a-a in Figure 5;

Figure 6 schematically shows the interior of a support structure configured to provide a flow battery for storing generated electrical energy, Figure 6a shows a cross section through the line a-a in Figure 6 and Figure 6b shows a cross section through the line b-b in Figure 6; and

Figure 7 shows, schematically, an alternative arrangement of support structures configured to provide a flow battery, Figure 7a shows a cross section through line a-a in Figure 7, Figure 7b shows a cross section through line b-b in Figure 7 and Figure 7c shows a cross section through line c-c in Figure 7.

Detailed description of embodiments

Numerous modifications, adaptations and variations in the embodiments described herein will be apparent to one skilled in the art having the benefit of the present disclosure and such modifications, adaptations and variations resulting in additional embodiments of the present invention are also within the scope of the appended claims.

The solar parking lot described in the embodiments below allows for the generation of renewable energy for business, domestic use, and/or for recharging electric vehicles. Embodiments also additionally or alternatively provide for energy storage in the form of gas tanks, such as hydrogen tanks, and/or battery systems, either or both of which may be located within the support structures of the parking structure itself. Where the parking structure provides hydrogen storage, it may be provided for dispensing stored hydrogen to hydrogen-powered vehicles. The system contains many novel and inventive design benefits as detailed further below.

Figure 1 shows a car park 10 comprising a plurality of support structures 12, spaced at intervals along the length of the car park and separated by a span between the support structures. The support structures support a roof, which is arranged to support or house solar panels or solar thermal boxes for electricity production or water heating etc. The support structures are typically spaced at intervals (i.e. spans) of 8 to 14 m and typically these spans correspond to several adjacent vehicle parking spaces on the ground below. Multiple spans between support structures may be achieved and in some cases spans of around 18 m may be used. Depending on the installation, the roof may extend between a single support structure and a building, rather than between multiple support structures.

Each support structure 12 is arranged such that the roof is supported at an angle (typically a few degrees) to the horizontal as appropriate for the location, preferably to maximize sunlight exposure thereby improving solar performance. Means may be provided to adjust the angle of the solar panels relative to the roof or the angle at which the roof is supported by the support structures relative to the ground. The support structure 12 comprises a hollow structure, typically molded from glass-reinforced plastic (GRP) or fiber-reinforced plastic (FRP) to form a base, or trunk, portion 14 and a roof support, or branch, portion 13. The composite material of the hollow structure may be reinforced with carbon fiber or other types of fibers, in particular sustainable materials such as hemp fibers, flax fibers, and/or basalt fibers. Sustainable plant-based epoxy resins may also be used in the construction. In the arrangement of Figure 1, the trunk portion is substantially vertical and approximately central to the support structure and extends vertically about a central vertical axis of the structure (not shown), although other configurations of the support structure may be provided, for example as described below in connection with Figure 4b. As shown in Figures 1 and 3, the trunk portion is fixed to the ground to anchor the parking structure. In the illustrated embodiment, the branch portion 13 extends from the trunk portion 14 to form two branches 13a, 13b extending in opposite directions outwardly from the trunk portion and providing a flat upper surface 13c providing support for the roof 20 (shown in an exploded view in Figure 1, separated from the support structures on which it rests in the assembled parking structure). In some embodiments, as shown, the branches 13a, 13b may be substantially equal throughout their lateral extension from the trunk while in other embodiments (not shown), they may vary in length such that the branch portion may extend predominantly in the direction of one or the other branch only. The arrangement of the branches is typically such that the roof covers the length of one or two car parking spaces arranged perpendicular to the direction of the span, plus a small additional amount of overhang to provide added weather protection for vehicles parked in said parking spaces.

The use of materials such as GRP/FRP to form a hollow structure allows the support structures to be repaired in response to damage, for example caused by collisions with vehicles using the car park, by cutting out and replacing the damaged portions of the structure shell. Portions of the structure can also be replaced in the same way for other reasons, for example to replace or upgrade EV charging sockets as required, thus allowing flexibility in the functionality of the car park.

The support structure may be formed from a single component or, as shown in Figure 3, the trunk portion 14 and the branch portion 13 may be separate components that are connected, for example bolted, to each other. At least some portions of the support structure may be provided with a composite core to improve structural rigidity, which may be formed from, for example, a PVC or PET foam.

As shown in Figures 1 and 2, the roof itself may be formed from one or more roof elements extending between adjacent support structures in the span direction and preferably from a plurality of such roof elements extending in parallel between adjacent support structures. Each roof element may be configured in the form of a tray 22, 24 comprising a flat base 25 and side walls 26a, b extending substantially perpendicularly from the base, as shown in cross section in Figure 2. Figures 1 and 2 show a portion 20 of a roof, the illustrated portion comprising three side trays of a length arranged to extend between two adjacent support structures 12. In some embodiments, a complete roof may comprise nine parallel trays, for example, each typically having the length of the span between adjacent support structures, although it will be appreciated that other arrangements are possible (for example, roof elements having the length of two or more spans or roof elements joined together along the span between support elements).

As shown in Figure 2, in a preferred embodiment, the roof-forming trays are arranged side by side and connected to each other along their side walls 26a to form the roof. The trays 22, 24 may be bolted together or joined by other means to form a rigid roof structure. Typically, the trays are connected to each other to form a complete roof span and then connected (e.g., by bolting) through their ends to the vertical support structures to form the carport. The trays may be made of FRP/fiberglass and may have a foam core or a PET plastic core (e.g., made from recycled plastic bottles) or other lightweight foam core material.

As shown in Figure 2, every other tray 22, 25 may be formed with a covering flange 27, typically 50 mm wide, along the distal edges of its extended side walls 26a, b. Staggered trays 24 may then seat against the flanges of adjacent trays. This provides increased rigidity and may also be used to form a watertight seal between adjacent trays. In some embodiments, this watertight seal may also provide an escape route to direct rainwater to a storage tank within the support structure 12 on which the roof is supported. This arrangement of trays has been found to provide a strong roof structure capable of supporting a greater weight of solar panels than conventional parking lot roof structures. Alternatively, each tray may be identical and the cover tab may be formed on a side wall of each tray such that the side wall of each tray that is provided with a cover tab abuts against the side wall of an adjacent tray that is not provided with a tab and seats against the tab of the adjacent tray.

When the roof elements are formed as trays (as shown in Figure 2), such trays may be fitted in one of two orientations, i.e., (i) in an “upright” configuration with the base 25 at the bottom and the side walls 25 extending upward; or (ii) in an “inverted” configuration (shown in Figure 2) in which the base 25 is at the top and the side walls 25 extend downward. The choice of orientation may depend on the type of solar panel technology being supported by the roof, for example, solar PV, solar thermal, or other. For solar PV panels, an inverted configuration may be preferred to provide a flat surface to allow air to flow beneath the solar PV panels to provide cooling. In such a case, the solar PV panels may be bolted or clamped to the trays. In an installation that includes solar thermal panels, it may be preferred to locate said panels using the trays in a vertical configuration, such that the panels sit within the trays and the walls 26a, b assist in locating the panels, although the panels may still be attached by bolts or clamps to the trays.

It will be appreciated that other forms of roof structure may be provided instead of the arrangement shown in Figure 2. For example, the roof structure may comprise one or more beams of an appropriate cross section, for example "T" beams or "I" beams.

Referring to Figure 3, a support structure 12 is shown in more detail. As mentioned above, the support element 12 extends between the distal tips of the two branches 13a, 13b over a distance typically slightly greater than the length of one or more parking spaces, depending on the configuration of the parking lot relative to the parking spaces below it. The width of the support structure 12 in a perpendicular direction (i.e. in the span direction) may typically be in the region of 400 mm.

In the embodiment shown in Figure 3, the trunk portion 14 and the branch portion 13 are formed as separate components and are bolted together or joined by other means. The bottom of the trunk portion 14 is anchored to the ground, in this case by bolts 16. Figure 3 also shows a plan view of the footprint 30 of the trunk portion 14 of the support structure 12, showing that the trunk portion comprises a hollow structure having a substantially elliptical cross section. In one embodiment, the trunk portion is anchored to the ground by providing a flange (not shown) extending inwardly from the perimeter to the bottom of the trunk portion where it meets the ground so as to provide a substantially horizontal surface abutting the ground within the hollow trunk portion. The flange may then be fastened to the ground surface, for example using a plurality of bolts, before the branch portion is connected to the trunk portion (so that access to the interior of the trunk portion is provided before the branch portion is fixed) or alternatively the inner flange may be accessed through an access panel or inspection hatch provided in the trunk portion. This arrangement provides a mechanism for securing the support structure to the ground whilst being hidden from view from the exterior of the structure.

In an extreme view (not shown), the lower portions of the branches 13a, 13b are elliptical becoming concave as the branch approaches the trunk portion. The upper portion 13c of the branch portion 13 is flat but is usually inclined a few degrees from the horizontal, as shown in Figure 3.

Inspection hatches may be provided in the side or top of the support structure to allow access to bolts, cables and other equipment housed within the support structure which may include antennas, inverters, data recorders, mobile phone transmitter receivers, Wi-Fi boosters and other electronic equipment. More generally the support structure may be used to house, internally or externally, antennas for all types of telecommunications including Long Term Evolution (LTE) for wireless broadband communications for mobile devices and data terminals, currently based on GSM(Global System for Mobile Communications)/EDGE (Enhanced Data Rates for GSM Evolution) and UMTS (Universal System for Mobile Telecommunications)/HSPA (High Speed Packet Access) technologies. The support structures described provide an advantage in not being formed from metal, therefore avoiding interference with wireless signals which is the biggest barrier to all wireless technologies, in particular the latest developments in 5G.

As shown in Figure 3, the legs 13a, 13b of the branch portion 13 form a variable inertia beam, in which each leg tapers towards its distal tip so that the weight of each leg (and its moment of inertia) is reduced towards its tip, reducing the load towards the ends of the cantilevered legs. In particular, this is achieved in the arrangement of Figure 3 by a tapered curve on the underside of the branch portion, opposite the flat upper surface 13c.

The hollow volume of the support structures described above may advantageously be used to provide a battery storage compartment for storing one or more batteries, used to store electricity generated from the car park's PV solar panels and/or for use in EV charging and/or for use as back-up batteries to maintain the car park's electrical functionality in the absence or failure of another power source. In particular, the hollow structure may be used to store lithium ion (Li-ion) or lithium iron phosphate (LiFePO) batteries with spaces provided in the hollow internal volume of the structure. The battery system may have connection means on the exterior of the support structure (e.g. in the form of an EV charging point or other type of power terminal for any of a variety of known uses) or the batteries may be used to power other functionality of the car park such as a mobile device charging point or an electronic display for use as information displays, advertising spaces, user interfaces, payment points for EV charging or parking, etc. The battery can be charged by one or more PV solar panels located on the roof of the parking garage above the supporting structure.

Variations of these arrangements are described below with reference to Figures 6 and 7, in which a flow battery is integrally formed within the hollow structure of the support structure itself, rather than a preformed Li-ion or LiFePO battery being housed within the hollow structure.

Alternatively, an EV charging point may be provided on the support structure with power supplied via a connection to the mains in which case any required components may be housed within the storage compartment within the support structure as required. In this arrangement, power may also be supplied to the grid from the PV solar panels housed by the car park. In some cases power may also be supplied to the grid by batteries stored within the support structure and/or by vehicles connected to an EV charging point, for example to provide grid support if the grid is under heavy load.

Figures 4 through 7 show several additional arrangements of support structures and other features which can be used in the parking lot of Figure 1.

Referring first to Figures 4 and 5, these figures illustrate arrangements in which the hollow structure of a support structure is used to store hydrogen, in particular for dispensing to hydrogen-powered vehicles such as hydrogen fuel cell vehicles or hydrogen internal combustion engine vehicles.

Figure 4 shows an arrangement in which the hollow support structure 40 is substantially as described above in which the internal cavity within the structure is used to house one or more hydrogen storage tanks 41, 42, 43, 44 for storing hydrogen that is used to fuel hydrogen powered vehicles. Such vehicles may conveniently be parked proximate to or below the parking structure. Figure 4 shows two tanks 42, 43 located within the central portion of the structure 40 and additional tanks 41, 44 located within the branches of the structure. It will be appreciated that any of the illustrated tanks may be provided in combination or individually as alternatives. Although two tanks 41, 44 are provided within the respective branches, which may provide an even more even load distribution on the structure, in some examples a tank or tanks may be provided in only one of the branches of the support structure. The tank or tanks provided within the support structure 40 may be configured to have any shape and in particular a shape that provides a required structural integrity and/or makes efficient use of the available space within the hollow support structure. In one example, as illustrated, the tank or tanks may be substantially cylindrical, particularly where the tanks store hydrogen at high pressures.

Figure 4a shows a cross section of the support structure 40 through the line a-a in Figure 4 and shows that the tank 42 is located within the structure such that it is completely surrounded by the material of the support structure 40. This allows the outer material of the support structure to be configured to provide the tank with appropriate impact protection, thermal protection, fire protection, chemical protection, etc., as may be required to enable hydrogen storage tanks to meet required safety standards and as set out in more detail below.

In the illustrated arrangement of Figures 4 and 4a, tanks 42 and 43 extend from substantially ground level to the top of support structure 40. However, in other examples, these tanks may be elevated above ground level and in particular above a level at which they would be susceptible to direct impact damage from a vehicle impacting the support structure 40. This protects the tanks from the risk of damage and potential rupture in the event of a vehicle impacting the structure. Similarly, any tanks located in the branches of the structure, such as tanks 41 and 44 illustrated, are protected from damage since they are located above the height of the vehicles that the parking structure is intended to accommodate. The location of one or more tanks in these branches therefore makes convenient use of the available space within the hollow structure, while locating the tanks away from the risk of a direct impact by a vehicle.

Where the structure is made from a FRP material, it will be appreciated that it can, advantageously, be repaired in the event of impact damage, for example by cutting out and replacing damaged sections of the structure with new FRP panels.

The structure 40 may also be provided with appropriate means (not shown) for filling the tank(s) with hydrogen and for dispensing stored hydrogen to vehicles. Such means may comprise compression and cooling means for dispensing hydrogen to vehicles at pressures above, but not limited to, about 700 bar and will be known to one skilled in the art. The tanks provided in the support structure may be arranged to store hydrogen at pressures of between 20 and 200 bar (2 to 20 MPa). During a refueling operation, hydrogen may be supplied from the storage tanks via a compressor to a smaller high pressure storage tank immediately prior to refueling to allow transfer of hydrogen fuel to a vehicle tank at up to about 700 to 1000 bar (70 to 100 MPa). Alternatively, a compression system may be used to transfer hydrogen fuel directly from storage tanks in the support structure to the vehicle fuel tank, without intermediate high pressure storage. It will be appreciated that one or more high pressure storage tanks may be provided within one or more of the support structures, for use as high pressure tanks during the refuelling operation.

Although the support structures of Figures 1, 3 and 4 are each shown comprising an upper branch portion having two branch members extending laterally in opposite directions, the branch portions may be arranged in different configurations. In particular, the support structure may comprise only a single laterally extending branch member. Where only a single branch member is provided, the single branch member may be either of the branch members illustrated in these figures, for example, either the upper branch member 13a or the lower branch member 13b as shown in Figure 3.

Figure 4b shows an alternative example of a hollow support structure 46, arranged to house hydrogen storage tanks in a manner similar to Figure 4a but in which the support structure comprises a trunk portion and only a single laterally extending branch member 46a, corresponding approximately to the upper branch 13a of the structure shown in Figure 3. The arrangement in Figure 4b is generally similar to that shown in Figure 4 and similar reference numerals are used to indicate similar components. In the arrangement shown in Figure 4b, hydrogen storage tanks 41, 42 and 43 are shown located within the hollow support structure 46, with the storage tank 41 located in the branch member 46a and the storage tanks 42 and 43 located within the trunk portion of the structure 46. Figure 4c shows a cross section of the support structure 46 through the line a-a in Figure 4b and shows the tank 42 located within the trunk of the structure 46 and the tank 41 located with the branch member 46a with both tanks being completely surrounded by the material of the support structure 46 to allow the outer material of the support structure to be configured to provide the tank with appropriate impact protection, thermal protection, fire protection, chemical protection etc. as set forth further below.

It will be appreciated that a support structure arrangement having only a single laterally extending branch member, for example as shown in Figure 4b, may be used in any of the other described embodiments of a parking structure and may be substituted in place of the support structure arrangement illustrated in any of the figures.

Figure 5 shows an arrangement similar to that of Figure 4, but in which the hollow support structure 50 is used to provide an integral storage tank for the storage of a volume of hydrogen 52. To meet appropriate safety requirements, the hollow structure may be a FRP structure as described above and the inner surface of the hollow structure may be provided with an additional protective material to provide a robust integral storage tank for safe and effective containment of the hydrogen. Such protective material may be selected to provide impact protection, thermal protection, fire protection, chemical protection, etc. as set out in more detail below.

Figure 5a shows a cross section of the support structure 50 through the line a-a in Figure 5 and shows that in this arrangement substantially the entire interior volume of the hollow structure 50 may be used as an integral storage tank although it will be appreciated that any portion of the hollow structure may be used to form such an integral storage tank. For example, in an alternative arrangement only the upper branch portions of the structure may be used to allow hydrogen to be stored in the volume of the hollow structure above a height at which the structure would be susceptible to impact damage from a vehicle impacting the support structure, as described in connection with Figure 4.

As with the arrangement of Figures 4 and 4c, the structure 50 may also be provided with suitable means (not shown) for filling the hydrogen tank(s) and for dispensing stored hydrogen to vehicles.

Referring now to Figure 6, there is shown an arrangement in which a battery is provided within the hollow support structure 60 and in particular in which the battery is provided as a flow battery. In the illustrated arrangement, the flow battery is provided as an integral flow battery in which the hollow volume of the support structure is used to provide integral electrolyte storage tanks as described below which are formed from the support structure itself but the flow battery may also be implemented using separate storage tanks which are housed or mounted within the hollow volume of the support structure.

As shown in Figure 6, the hollow support structure 60 is provided with a positive electrolyte (anolyte) tank 61, a negative electrolyte (catholyte) tank 62 and an electrochemical cell 63. The electrochemical cell comprises two electrodes 64, 66 separated by a semi-porous membrane 65. Figure 6a shows a cross section along the line a-a in Figure 6 and illustrates the membrane 65 located between the two electrodes 64, 66. Figure 6b shows a cross section along the line b-b in Figure 6 and illustrates the surface of the membrane 65 and its shape in this particular example. It can be seen that the membrane in this case runs the entire height of the support structure 60 and has a narrower width corresponding to the depth of the support structure.

Pumps 67a, 67b are provided to pump the respective electrolytes from the electrolyte tanks through the electrochemical cell and past the membrane where ion exchange takes place to convert chemical energy into electricity. The electrolyte circulated through the electrochemical cell 63 by the pumps returns to the respective electrolyte tanks through return lines 68a, 68b.

The battery may be used to store electrical energy generated from solar cells mounted on the roof of the support structure as described above and/or to store electricity provided from the power grid or generated by other means, in particular other forms of renewable energy generated at or around the site on which the parking structure is located. The battery may also be used to supply electricity to electric vehicles located beneath or around the parking structure, for example from a charging point (not shown) provided in the trunk of the support structure and therefore readily accessible to a vehicle parked beneath the parking structure. The battery may alternatively or additionally be used to supply electricity to the grid. An inverter 69 may be provided to convert direct current (DC) from the battery to alternating current (AC) for use in charging electric vehicles or to supply other loads or electricity transmission requirements.

In one example, the flow battery may be a vanadium flow battery or a vanadium redox battery which may utilize vanadium-based electrolytes and carbon-based electrodes. Alternatively, the flow battery may be a zinc-bromine battery. However, other battery chemistries and flow battery operations may be provided which may make use of the ability to conveniently store the relevant components within the hollow volume of the support structure 60.

The electrolyte tanks may conveniently be provided on respective opposite branches of the support structure and the substantially vertical trunk portion of the support structure may be used to house the electrochemical cell 63. In this manner, the hollow volumes of the branches, which form a significant portion of the internal volume of the support structure, advantageously provide volumes for the electrolyte storage tanks, which volumes determine the storage capacity of the battery and the substantially vertical trunk portion conveniently provides a large linear contact area between the electrolyte storage tanks to facilitate the electrochemical reaction along the electrodes when the electrolytes are circulated.

By using electrolyte storage tanks that are integrally formed within the hollow structure of the support structure, particularly at the branches, it is possible to maximize the effective use of the hollow space within the structure and increase the energy density of the battery.

Furthermore, due to the configuration of the support structure, it may be possible, in some flow battery arrangements, to make use of gravity to assist with the circulation of electrolyte from the storage tanks through the electrochemical cell, in particular where the electrolyte storage tanks are located in the branches of the support structure. Pumps may then be used to assist with the circulation of electrolyte back through the storage tanks.

Figure 7 shows a further arrangement of a flow battery system in which multiple individual support structures of the parking structure are used as different elements of the flow battery. In particular, Figure 7 shows an arrangement in which three adjacent support structures 70, 72, 74 are used respectively to provide a negative electrolyte tank, an electrochemical cell and a positive electrolyte tank. The flow battery operates in substantially the same manner as in the arrangement of Figure 6, but the flow battery elements are housed in different parts of a parking structure comprising multiple hollow support structures. For example, the three support structures 70, 72 and 74 may support a roof structure (not shown) via at least the three support structures which in turn may support a solar cell array (not shown) as described above and may provide space to house parked vehicles below the roof and between the support structures. By deploying the battery across the multiple support structures that are used to support the roof of the parking garage that extends between them, the parking structure is provided with a battery having a larger total volume that can accommodate the electrolytes and the electrochemical cell and thus a battery with a larger storage capacity can be provided. This arrangement also advantageously combines the structural elements of the parking garage with elements that form the flow battery to make efficient use of the space at the parking site.

The flow battery arrangement of Figure 7 operates in substantially the same manner as the arrangement of Figure 6 except that the electrolyte tanks and the electrochemical cell are provided in separate hollow structures and are connected by appropriate supply lines to allow electrolyte to circulate between the structures to operate the flow battery. Support structures 70 and 74 are used to provide a negative electrolyte tank and a positive electrolyte tank respectively, which may be integrally formed from the hollow structure of the support structure itself to maximise the available tank volume within the structure or may be formed using one or more storage tanks housed within each support structure. Figure 7a shows a cross section of the support structure 70 through the line a-a in Figure 7 and shows that in this arrangement substantially the entire interior volume of the hollow structure 70 may be used as an integral storage tank although it will be appreciated that any portion of the hollow structure may be used to form such an integral storage tank. For example, in an alternative arrangement, only the upper branch portions of the structure may be used to store electrolyte in the volume of the hollow structure above a height at which the structure would be susceptible to direct impact damage from a vehicle impacting the support structure. Figure 7c similarly shows a cross section of the support structure 74 through the line c-c in Figure 7 and shows that in this arrangement, substantially the entire interior volume of the hollow structure 74 may be used as an integral storage tank for storing negative electrolyte although again it will be appreciated that other configurations may be contemplated as described in connection with Figure 7a.

The support structure 72 is arranged to provide the electrochemical cell through which the electrolyte is circulated by pumps 77, 78. Figure 7b shows a cross section along the line b-b in Figure 7 and illustrates the membrane 75 located between two electrodes 81, 83. In the illustrated arrangement the membrane 75 runs vertically between the top and bottom of the interior of the support structure 72 to divide its hollow volume into two sections to separate the negative electrolyte 71 on one side from the positive electrolyte 73 on the other side. The operation of the flow battery uses the same principle as the arrangement of Figure 6. The pump 77 circulates negative electrolyte from the negative electrolyte tank provided by, or within, the support structure 70 through a supply line 84 connected between the support structure 70 and the support structure 72, through a volume within the support structure 72 on a first side of the membrane 75 and past the electrode 81. The circulating negative electrolyte 71 is returned to the negative electrolyte tank through a return line 85 connected between the support structure 72 and the support structure 70. Similarly, pump 78 circulates positive electrolyte from the positive electrolyte tank provided by or within support structure 74 through a supply line 86 connected between support structure 74 and support structure 72 through a volume within support structure 72 on a second side of membrane 75 and past electrode 83. The circulating positive electrolyte 73 is returned to the positive electrolyte tank through a return line 87 connected between support structure 72 and support structure 74. The electrodes, membrane, and electrolytes may be the same as those used in the arrangement of Figure 6 or may be selected from any other material and chemical composition suitable for flow battery operation. Although the positive and negative electrolyte tanks and the electrochemical cell are shown in Figure 7 as occupying the entirety of the respective support structures 70, 72 and 74 it will be appreciated that the tanks and cell may be housed in any suitable portion of the respective structures. Furthermore, the tanks and cell may be housed in more or less than the three illustrated support structures, for example by providing positive electrolyte tanks in two or more support structures, negative electrolyte tanks in two or more support structures and connecting these four or more tanks to a separate support structure configured to provide the electrochemical cell.

Although supply lines 84 and 86 are shown supplying electrolyte into the top of the electrochemical cell and return lines 85 and 87 are shown returning electrolyte from the bottom of the electrochemical cell to the electrolyte tanks, other configurations of supply and return lines may be provided to circulate electrolyte through the electrochemical cell. For example, electrolyte may be supplied to the bottom of the electrochemical cell and pumped upward through the cell and returned from the top of supply structure 72 to the electrolyte tanks. Similarly, supply lines 84 and 86 as well as return lines 85 and 87 are shown connecting to the bottom of the negative and positive electrolyte tanks of support structures 70 and 74, but alternative configurations may be used. For example, electrolyte may be supplied from the top of the tanks and returned to the bottom or vice versa. It will also be appreciated that although two pumps 77, 78 are shown for circulating the electrolyte, different circulation arrangements may be provided, including different pumping arrangements, various types of pumps and/or different numbers and positions of the pumps.

In addition, it may be possible in some arrangements to make use of gravity to assist with the electrolyte circulating from the storage tanks through the electrochemical cell. For example, gravity may be used to assist with the feeding of electrolyte from the bottom of the electrolyte tanks into the electromechanical cell by supplying the electrolyte from the bottom of the tanks to the cell.

An inverter 89 may be provided as described in connection with Figure 6.

The hollow support structures illustrated in the figures may be constructed from a variety of materials that enable them to provide the degree of protection required in a given application. For example, hydrogen storage tanks such as those described in connection with figures 4 and 5 may meet certain safety requirements including standards relating to, for example, burst testing, impact testing as well as pressure, leak, fatigue, temperature and fire testing, among others. Similar safety requirements will also apply to the electrolyte storage tanks described in connection with figures 6 and 7, which may need to meet standards relating to, for example, impact resistance, leak testing, mechanical strength and/or temperature testing, among others.

The installation of hydrogen or electrolyte storage tanks within hollow support structures allows the construction of the support structures themselves to provide some or all of the required protection. In some cases, such tanks may be provided as separate components that already meet safety and performance requirements and are housed within the hollow support structures. The support structure may be made of FRP and may be reinforced with carbon fibres, aramid fibres or various forms of flax or hemp fibres. In this case, the support structure may be provided with an additional degree of protection for the discrete tanks by providing additional impact, temperature, fire or chemical protection, for example. Foam material filling may be provided in the gaps between the support structure and a tank housed within it to provide additional thermal insulation, impact protection or fire protection, for example. Any materials provided within the hollow support structure may also be selected and arranged to provide sound insulation, for example to soundproof the pumps 67a, 67b shown in the flow battery arrangement of Figure 6 or any other equipment housed within the support structures. In particular, such soundproofing may be provided by including foam padding at selected locations within the hollow support structure as appropriate.

Where a discrete tank is mounted within the supporting structure, it may also be possible for the supporting structure material to provide additional protection to a tank that would otherwise not be able to meet the specified regulatory requirements, so that the combination of tank construction and supporting structure meets the specified requirements for the entire installation.

Suitable tanks for hydrogen storage may include those used in hydrogen powered vehicles, for example, and such tanks may be used or adapted for location within support structures. Such tanks may be constructed from polymer-based materials and may include composite materials which may utilize an epoxy resin matrix. In particular, epoxy resin may provide the required degree of fire protection in a composite material. Suitable composite materials may be reinforced using carbon fiber, glass fiber or synthetic aramid fibers such as Kevlar in wicks or fabrics. Alternatively, tanks may be made from stainless steel or aluminum, reinforced with carbon fiber, glass fiber or aramid fibers for example wound around a cylindrical metal tank to provide suitable force and impact resistance. In other examples, a coating of aluminum or steel with glass, aramid or carbon fiber may be used to form a metal matrix composite material. In some examples, suitable tanks comprise a carbon fiber coated with a polymer material. Combinations of steel and/or a composite material can provide tanks capable of storing hydrogen at pressures up to around 700 bar (70 MPa).

When the tank is installed within the hollow support structure, the support structure can provide additional structural integrity to the tank and therefore improve the overall performance of the tank.

Where a hollow support structure is used to provide an integral storage tank for hydrogen (such as in Figure 5) or battery electrolyte (such as in Figures 6 and 7), the support structure may comprise a FRP material or be clad with a suitable composite material which is constructed to provide the required pressure rating and meet other performance criteria as set out above.

Suitable tanks for flow battery electrolyte storage, such as may be used in the arrangements of Figures 7 and 8, may include polymer or stainless steel tanks and may be made of other suitable materials conventionally used for flow battery electrolyte storage. Where a hollow support structure is used to provide an integral storage tank for flow battery electrolyte storage, the support structure may comprise a FRP material and may be internally coated or lined to provide suitable chemical resistance to the structure to enable its use as a storage tank. For example, chemically resistant glues, resins or gel coatings may be applied to the interior of the structure to provide a suitable internal surface for use as an electrolyte storage tank and/or the interior of the support structure may be lined with any suitable material that provides the required chemical resistance.

Although the hydrogen storage embodiments of Figures 4 and 5 have been described as separate systems from the flow battery embodiments of Figures 6 and 7, it will be appreciated that hydrogen storage and flow batteries may be combined within multiple support structures of a single solar parking facility. In other words, a parking facility may comprise a plurality of illustrated hollow support structures supporting a roof extending therebetween, preferably supporting solar cells for generating electricity, and providing space between and around the support structures for vehicles to park beneath the roof structure. One or more support structures may be used to provide one or more flow batteries as described above, while other support structures may be used to provide hydrogen storage. In this manner, the parking facility may provide electricity generation and storage, as well as EV charging and hydrogen fuel delivery to vehicles. In some cases, a single support structure may include both hydrogen storage and battery storage and a single support structure may provide both hydrogen dispensing and EV charging points.

Furthermore, by providing hollow support structures that can accommodate both electrolyte storage tanks for use in a flow battery and hydrogen storage tanks, it is possible for these storage tanks to be interchangeable such that electrolyte storage tanks can be replaced with hydrogen storage tanks and vice versa. In this way, it is possible to provide a parking facility that is flexible and can be adapted to the needs of a particular location that change over time and also provides future-proofing for changing technologies. For example, the use of hydrogen storage in a solar parking structure may become more prevalent with the increasing use of technologies for the production of hydrogen from solar energy in which case greater capacity may be required for the storage of hydrogen produced on-site from the solar energy generated by the parking structure itself.

In particular, by configuring the support structures to provide adequate structural protection against impact, fire, etc., as discussed above, the structures may be suitable for both hydrogen storage and electricity storage. Similarly, by selecting appropriate materials and constitutions or the storage tanks, whether installed within support structures or integrally formed from the support structures themselves, the storage tanks may be configured to suitably store either hydrogen or a flow battery electrolyte without changing the tanks. The support structures may then be reconfigured in the future, if required, to change a support structure being deployed as a hydrogen storage tank to a flow battery or vice versa, without having to replace the tanks.

The exterior surface of the described support structures may be used to provide a space for advertising and/or other means of user communication, such as display screens providing information or instructions, flexible or TFT electronic panels mounted flush with the surface of the support structure, or user interfaces such as touch screens for processing payments for EV charging, parking, etc. The contoured support structures (shown in more detail in Figure 1) may be covered with a PVC or synthetic film wrap to display advertisements or other branding or information.

It will be appreciated from the above description that the car park may be formed from support structures having a number of different advantageous features and the arrangements described in connection with the figures may be implemented in any combination.

The hollow nature of the structures allows for, without limitation, the following to be incorporated into the design of the structures: cables, conduits, electrical components, water pipes, water storage, battery integration. The hollow parking and support structures may also be used as a cellular telephone or Wi-Fi signal boosting apparatus since the support structures are preferably not formed using conductive materials (and are preferably formed from GRP and FRP) and will not act as an antenna or interfere with other Wi-Fi or signal boosting apparatus located within the cavity of the support structures. This provides a significant advantage over conventional parking structures which are typically constructed from steel and also do not provide an interior space to house such equipment. In some embodiments, the interior space of the support structures may be used to house Wi-Fi or cellular antennas or boosters instead of conventional antennas located anywhere in close proximity.

Although reference is made in this description to the use of GRP and FRP materials to form the parking support structures, other suitable materials, preferably other than electrically non-conductive materials, may also be used, particularly where these can be used to form a hollow support structure of the type illustrated to achieve advantages similar to those described.

Claims (15)

1. A solar parking lot comprising: at least one support structure and a roof supported by the at least one support structure, the roof being arranged to support at least one solar panel, the at least one support structure being formed from a fiber-reinforced plastic (FRP) material and comprising an outer shell enclosing an inner volume and at least one hydrogen storage tank located within the interior volume for storing hydrogen fuel for dispensing to a vehicle. 2. The solar parking lot of claim 1, wherein the at least one hydrogen storage tank is configured to store hydrogen at a pressure between 2 and 20 MPa. 3. The solar parking lot of claim 1 or 2, wherein the at least one hydrogen storage tank is formed from stainless steel surrounded by carbon fiber. 4. The solar carport of any preceding claim, wherein the at least one hydrogen storage tank is integrally formed by the interior volume of the at least one support structure. 5. The solar parking lot of any preceding claim, wherein at least one support structure comprises dispensing means for dispensing hydrogen stored in the storage tank to a vehicle. 6. The solar carport of any one of the preceding claims, wherein each support structure comprises a substantially vertical central trunk portion for mounting on the ground and a branch portion for supporting the roof, the branch portion comprising at least one laterally extending branch member. 7. The solar carport of claim 6, wherein at least one laterally extending branch member is shaped to provide a substantially flat upper surface for supporting the roof. 8. The solar carport of claim 7, wherein the branch portion comprises two branch members extending laterally in opposite directions and is formed from a single piece of fiber reinforced plastic (FRP) material. 9. The solar carport of claim 8, wherein the at least one storage tank is located above ground level, within at least one of the laterally extending branch members. 10. The solar carport of any one of the preceding claims, wherein the roof comprises a plurality of roof elements each extending in a direction so as to form a span between two spaced apart support members, each roof element arranged parallel to, and connected to, an adjacent roof element. 11. The solar carport of claim 10, wherein each roof element comprises a substantially planar base and side walls extending substantially perpendicularly from the base to form a U-shaped cross section, the roof elements arranged such that the side walls of adjacent roof elements abut each other and are connected to each other along the length of the span. 12. The solar carport of claim 11, wherein at least one roof element and preferably every other alternating roof element is provided with a laterally extending flange extending from a distal edge of at least one side wall and arranged to seat against the distal edge of the side wall of an adjacent roof element. 13. The solar carport of any one of claims 10 to 12, wherein the roof elements are formed of fiber reinforced plastic (FRP), for example fiberglass, with a foam or polyethylene terephthalate (PET) core. 14. The solar parking lot of any of the preceding claims, further comprising at least one solar panel, in particular a photovoltaic (PV) solar panel or a thermal solar panel, mounted on the roof. 15. The solar parking lot of any of the preceding claims, further comprising at least one solar thermal panel, mounted on the roof and a storage tank located within the cavity of the at least one support structure, the at least one solar thermal panel arranged to heat water for storage in the storage tank.