GB2525853A

GB2525853A - A solar array

Info

Publication number: GB2525853A
Application number: GB1407699.6A
Authority: GB
Inventors: Richard Wakefield
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-05-01
Filing date: 2014-05-01
Publication date: 2015-11-11
Also published as: GB2528742B; GB201407699D0; GB2528742A; GB201507572D0

Abstract

A solar array 1 comprising at least one photovoltaic module 2 arranged in use to extend in a hemispherical, spherical or cylindrical manner, and at least one lens array 3 to focus light onto the photovoltaic modules. The lenses may be arranged in a spherical geodesic dome configuration. A helical solar water heater may also be arranged within the assembly.

Description

A solar array

Field of the Invention

The present invention relates to a solar array. More particularly, the present invention relates to a solar array for providing electrical power that is configured so that sunlight falls directly onto the array for all positions of the sun throughout the day and year.

Background

The use of solar arrays for the provision of power is becoming increasingly common.

Solar arrays generally consist of a number of individual cells or panels arranged in a flat planar array, mounted on a support structure so that the array is held angled towards the sky. Generally, solar arrays will be mounted in a fixed orientation. For example, in the northern hemisphere, the sun rises in the east, and sets in the west, tracking through south in the middle of the day. Solar arrays in the northern hemisphere will generally be arranged facing southwards so that the maximum amount of ambient sunlight will shine on them over the course of a day. Solar arrays can be mounted on a support framework, or can use existing features such as angled roofs to provide support.

One issue with the use of fixed planar arrays is that light from the sun will only impinge directly onto the array (that is, substantially perpendicular to the panels of the array) over certain limited periods of the day and year. At all other times, the light impinges at an angle, which does not provide maximum efficiency. Mounting the array in a fixed position is a compromise between increased efficiency (by angling the array directly towards the sun at all times), and increased complexity (by including a moving or movable mount and a means to move this to the most efficient angles for any given location of the sun). Generally, for the sake of simplicity and reliability, arrays are fixed rather than moving or movable.

Prior Art

Accordingly a number of patent applications have been filed in an attempt to resolve the problem or similar, including the following: JP2011181540 describes and shows a spherical rotating body having a solar cell as part of the surface. The cell has a rotary shaft at the surface on an axis passing through the centre of the spherical body from the surface of the spherical body, and has a curved reflecting plate covering at least a part of the spherical body. The axis of the spherical body is combined with the shaft of a motor to rotate. The motor is supported by a supporting member.

KR20120029870 describes and shows a solar cell module that includes a spherical surface, a spherical transparent outer part, and a spherical transparent inner part.

The inner part includes a receiving groove corresponding to a shape of a solar cell panel. The solar cell panel is electrically connected in series or parallel.

JP2009170749 describes and shows a spherical power generating system comprising solar cells arranged side by side in a frame of a spherical body. The system provides a power generation system comprising solar cells arranged side by side in a frame of a polyhedron such as for example a spherical body, a trigonal pyramid, or a hexahedron. The system is mounted at the upper end of one bracing strut via a joint, a circular cone, and a cylindrical body.

In contrast the present invention provides a solar power array that is better configured so that sunlight falls effectively onto the array for all positions of the sun throughout the day and year.

Summary of the Invention

According to the present invention there is provided a solar array comprising: at least one photovoltaic module arranged in use to extend in a non-planar manner, and; at least one light directing means arranged in use to receive light remote from the at least one photovoltaic module and transmit this light through the light directing means towards and onto the at least one photovoltaic module.

The light directing means allows the harvesting of increased amounts of light as light that would otherwise not fall directly on the photovoltaic module can be harvested, and the non-planar photovoltaic module allows a greater proportion of the light incident on the photovoltaic array to fall substantially more effectively and/or directly than if a planar module was used, increasing efficiency.

Preferably, the at least one photovoltaic module comprises a plurality of solar voltaic modules. Using a plurality of modules allows a greater variety of configurations.

Preferably, the light directing means comprises at least one light-transmitting lens supported remotely from the at least one photovoltaic module and configured to receive incident light and transmit this to the at least one photovoltaic module. The properties of lenses are well understood, and lightweight and robust lenses can be produced easily and inexpensively.

Preferably, the at least one light-transmitting lens is configured to focus the incident light. Focussing the light allows a lens to be used that is larger than the target area, allowing the harvesting of a greater amount of incident light for a given size of photovoltaic module.

Preferably, the solar array further comprises a plurality of light transmitting lenses arranged and supported remotely from the at least one photovoltaic module, each lens configured to receive incident light and transmit this to the at least one photovoltaic module. The use of a large number of lenses allows the harvesting of a greater amount of incident light.

Preferably, the light transmitting lenses are arranged in a mutually supporting structure. This helps to increase efficiency and keep the weight as low as possible.

Preferably, the light transmitting lenses are arranged in a substantially unbroken array. This helps to increase efficiency and keep the weight as low as possible.

Preferably, the lenses are arranged to maximise the incident sunlight footprint. This allows the maximum amount of incident light to be harvested at all times of the day and throughout the year.

Preferably, the lenses are arranged substantially at least hemi-spherically. This provides an efficient shape for harvesting the maximum amount of incident light at all times of the day and throughout the year.

Preferably, the lenses are arranged substantially spherically. This provides an efficient shape for harvesting the maximum amount of incident light at all times of the day and throughout the year, and ensures that the solar array can be emplaced in any orientation.

Preferably, the at least one photovoltaic module is substantially at least hemi-spherical. This provides an efficient shape for harvesting the maximum amount of incident light at all times of the day and throughout the year.

Preferably, the at least one photovoltaic module is substantially spherical. This provides an efficient shape for harvesting the maximum amount of incident light at all times of the day and throughout the year, and ensures that the solar array can be emplaced in any orientation.

Preferably, the at least one photovoltaic module is substantially a cylindrical segment. This provides an efficient shape for harvesting the maximum amount of incident light at all times of the day and throughout the year.

Preferably, the at least one photovoltaic module is substantially cylindrical. This provides an efficient shape for harvesting the maximum amount of incident light at all times of the day and throughout the year.

Preferably, the solar array further comprises a support stand configured to support the solar array. This allows the solar array to be emplaced.

Preferably, the support stand is configured to connect the solar array to the roof of a domestic residence. This allows the solar array to be fitted easily without the requirement for fitting large planar solar panels.

Preferably, the solar array further comprises a water heating means adjacent to the at least one photovoltaic module and configured to heat water via incident heat recovery. This maximises the efficiency of the overall unit.

Preferably, the water heating means comprises a metal coil configured to allow a stream of water to pass therethrough. This provides a simple and inexpensive construction.

Brief Description of Figures

Figure 1 shows a perspective view from one side and above of a first embodiment of solar array, having an array of photovoltaic modules configured in a spherical arrangement, and an array of lenses arranged spherically around the photovoltaic module array so that they can receive and transmit light from locations remote from the photovoltaic module array and transmit this to the photovoltaic module array, the solar array having a stand that extends from the bottom of the array to allow the array to be emplaced.

Figure 2 shows a perspective view of the solar array of figure 1 emplaced on the roof gable of a domestic residence.

Figure 3 shows a perspective detail view of the photovoltaic module array and the lens array of the solar array of figures 1 and 2.

Figure 4 shows a perspective view from one side and above of a second embodiment of solar array, having an array of photovoltaic modules configured in a cylindrical arrangement, and an array of lenses arranged spherically around the photovoltaic module array so that they can receive and transmit light from locations remote from the photovoltaic module array and transmit this to the photovoltaic module array, the solar array having a stand that extends from the bottom of the array to allow the array to be emplaced.

Figure 5 shows a perspective view of the solar array of figure 4 emplaced on the roof gable of a domestic residence.

Figures 6a -6c show views of the solar array of figures 1 to 3 in use in a variety of locations, and suitably scaled for use at each location.

Detailed Description of Figures

A first embodiment of the solar array of the present invention will now be described with reference to figures 1 to 3.

The solar array 1 of the first embodiment has two main parts: a photovoltaic module array 2, and an array of lenses 3.

The photovoltaic module array 2 comprises a number of individual photovoltaic modules, arranged in a spherical shape.

The lenses 3 are arranged in a sphere around the photovoltaic module array 2, the centres of each of the spheres (the lenses 3 and the photovoltaic module array 2) generally coincident). Each of the lenses 3 has the overall shape of a regular pentagon, connected at each edge to a neighbouring lens 3 to form the lens sphere.

Each of the lenses 3 is configured to both re-direct and focus incident light falling on the lens, and transmit this through the lens 3 towards the photovoltaic module array 2.

The relative sizes of the photovoltaic module array 2 and the lens sphere are formed such that maximum efficiency is achieved. The larger size of the sphere relative to the photovoltaic module array 2 allows a greater amount of incident light to be harvested, as light that would otherwise not fall directly on the photovoltaic module can be harvested. This can also be used as efficiently as possible. The maximum amount of light that each individual cell in the array 2 can process can be transmitted onto the surface of the cell -the cells can be flooded with light, allowing maximum efficiency to be achieved. The non-planar shape of the photovoltaic module array 2 and the sphere of lenses 3 means that a greater proportion of the light incident on the photovoltaic array 2 falls substantially more directly (i.e. not at an angle, or at least not a substantial angle) than if the module were flat or planar. This helps to increase the overall efficiency of the solar array 1. Using a spherical arrangement also means that sunlight will be harvested efficiently throughout both the full course of the day, and throughout the year. As the array 1 has a regular shape, whatever orientation it is emplaced in, it will present the same or substantially similar appearance when viewed from the position of the sun in the sky throughout the course of a day and over the course of a year. This ensures the maximum possible efficiency, as the maximum amount of light possible will be directed onto the photovoltaic module array 2 and this will fall substantially directly onto the cells, rather than at an angle.

A stand 4 extends from the bottom of the array 1, and allows the array 1 to be emplaced where required. As shown in figure 2, this could be for example on a roof gable. As the array 1 presents a substantially uniform aspect in all orientations, the orientation of the roof or other emplacement site is immaterial. As long as the location receives light then the array 1 will function at maximum efficiency. This overcomes a problem with planar panels, which in the northern hemisphere are required to be emplaced or positioned facing south -for example on a southwards facing slope of a roof. The use of planar arrays has therefore limited the number of locations at which a solar array can be positioned. Use of the solar array of the present invention assists with overcoming this inherent limitation with planar arrays.

The stand and the cylindrical shape of the array 1 allows quick and easy emplacement in the same manner as a satellite dish or television aerial are emplaced, obviating the requirement for the positioning of a number of flat panels, each requiring multiple fixing points.

A second embodiment of solar array 101 is shown in figures 4 and 5. In this embodiment, the photovoltaic module array 102 is cylindrical rather than spherical, and extends generally axially vertically. The array of lenses 103 is substantially the same as for the first embodiment, as is the stand 104. However, if required the positions or the refractive properties of the lenses 3 can be tuned or varied to take advantage of the cylindrical array 102, for example varying these to ensure that light is evenly dispersed along the length of the cylinder.

In this embodiment, the solar array 101 further comprises a water heating coil 105 wound around the photovoltaic module ariay 102. Water passes along the length of the coil 105 and is heated via incident heat recovery. There are a number of way in which the water is heated as it travels, including: focussed light impinging directly on the coil 105 from the lenses 103, radiated and convecting heat from the cylindrical array 102, and the greenhouse effect of being at least semi-enclosed within the sphere of the lenses 103. Providing hot water in this manner helps to maximise the efficiency of the array 101.

As outlined above, the lenses 3 and 103 are arranged in a sphere. It can be seen that a fully enclosed sphere is not necessary for a permanent or semi-permanent emplacement, as one side of the sphere will always be the dark side', or on the opposite side to the sun as the sun only ever completes a partial traverse (east to south to west in the northern hemisphere, never north). The lenses can be arranged in a suitable shape so that for all days of the year and for all the daylight hours of direct sunlight, the light will fall on the lenses and be redirected to the photovoltaic module array 2 or 102. That is, the lenses are arrayed in a pattern such that they will always be between the photovoltaic module array 2 or 102 and the sun. This allows the maximum amount of incident light to be harvested at all times of the day and throughout the year. Although the position and refractive indexes of each of the lenses in an array could be tuned for maximum efficiency for a given location, for simplicity the lenses can be arranged in a hemi-spherical or substantially hemi-spherical array. This provides a simple and efficient shape for harvesting the maximum amount of incident light at all times of the day and throughout the year, at all locations, and simple regular shapes help to simplify production.

Similarly, the photovoltaic module array could be hemi-spherical, or a cylindrical segment, either vertical, horizontal or angled between the two. This provides an efficient shape for harvesting the maximum amount of incident light at all times of the day and throughout the year for a permanent or semi-permanent emplacement. The dark side of the array of lenses 3 or 103 could be replaced by mirrors, possibly shaped to reflect and focus incident light back to the photovoltaic module array 2 or 102.

The solar array of the present invention can be scaled as appropriate for use. For domestic use and emplacement the outer diameter of the array of lenses 3 would be in the region of 1-2 metres, and the array would be mass-manufactured with simple regular shapes help to simplify production. and emplacement (which could be in any orientation). Similar sizes could be used for powering homes, schools, hospitals or similar in remote locations, for example in developing countries, or for emergency use in e.g. refugee camps or after natural disasters. Larger units could be used for office blocks, or on an industrial scale to provide power to a national or local grid. As these are larger items that will be one-offs, it is more cost-effective to tune these as required for the location, creating individually tuned lenses (and possibly mirrors) for the array to maximise efficiency and light harvesting.

The invention has been described by way of examples only and it will be appreciated that variation may be made to the above-mentioned embodiments without departing from the scope of invention. Firstly it will be understood that any features described in relation to any particular embodiment may be featured in combinations with other embodiments.

With respect to the specification therefore, it is to be realised that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.

Therefore, the foregoing is considered as illustrative only of the principles of the invention, with variation and implementation obvious and clear on the basis of either common general knowledge or of expert knowledge in the field concerned. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as set out in the accompanying claims.

Claims

Claims 1. A solar array comprising: at least one photovoltaic module arranged in use to extend in a non-planar manner; at least one light directing means arranged in use to receive light remote from the at least one photovoltaic module and transmit this light through the light directing means towards and onto the at least one photovoltaic module.
2. A solar array as claimed in claim 1 wherein the at least one photovoltaic module comprises a plurality of solar voltaic modules.
3. A solar array as claimed in claim 1 or claim 2 wherein the light directing means comprises at least one light-transmitting lens supported remotely from the at least one photovoltaic module and configured to receive incident light and transmit this to the at least one photovoltaic module.
4. A solar array as claimed in claim 3 wherein the at least one light-transmitting lens is configured to focus the incident light.
5. A solar array as claimed in claim 3 or claim 4 further comprising a plurality of light transmitting lenses arranged and supported remotely from the at least one photovoltaic module, each lens configured to receive incident light and transmit this to the at least one photovoltaic module.
6. A solar array as claimed in claim 5 wherein the light transmitting lenses are arranged in a mutually supporting structure.
7. A solar array as claimed in claim 5 or claim 6 wherein the light transmitting lenses are arranged in a substantially unbroken array.
8. A solar array as claimed in any one of claims 5 to 7 wherein the lenses are arranged to maximise the incident sunlight footprint.
9. A solar array as claimed in claim 8 wherein the lenses are arranged substantially at least hemi-spherically.
10. A solar array as claimed in claim 8 or claim 9 wherein the lenses are arranged substantially spherically.
11. A solar array as claimed in any one of claims 1 to 10 wherein the at least one photovoltaic module is substantially at least hemi-spherical.
12. A solar array as claimed in claim 11 wherein the at least one photovoltaic module is substantially spherical.
13. A solar array as claimed in any one of claims 1 to 10 wherein the at least one photovoltaic module is substantially a cylindrical segment.
14. A solar array as claimed in claim 13 wherein the at least one photovoltaic module is substantially cylindrical.
15. A solar array as claimed in any one of claims 1 to 14 further comprising a support stand configured to support the solar array.
16. A solar array as claimed in claim 15 wherein the support stand is configured to connect the solar array to the roof of a domestic residence.
17. A solar array as claimed in any one of claims 1 to 16 further comprising a water heating means adjacent to the at least one photovoltaic module and configured to heat water via incident heat recovery.
18. A solar array as claimed in claim 17 wherein the water heating means comprises a metal coil configured to allow a stream of water to pass therethrough.
19. A solar array substantially as herein described with reference to the figures.