Modular solar power and energy storage systems and methods

Abstract

A power generation device is provided. The power generating device includes a photovoltaic panel configured to generate a first type of electrical power, a power converter electrically coupled to the photovoltaic panel and configured to convert the first type of electrical power to a second type of electrical power for transmission to a grid and / or load, and at least one energy storage device electrically coupled to the power converter, the at least one energy storage device configured to store electrical energy provided by the power converter. The power generating device further includes at least one heat management component and at least one back housing physically attached to the photovoltaic panel and defining a space between the photovoltaic panel and the at least one back housing. The power converter, the at least one energy storage device, and the at least one heat management component are positioned in the space.

Description

MODULAR SOLAR POWER AND ENERGY STORAGESYSTEMS AND METHODSBACKGROUND

[0001] The field of the disclosure relates generally to solar power generation systems, and more particularly, to photovoltaic (PV) systems having integrated energy storage.

[0002] PV systems utilize PV panels to produce electrical power when the PV panels are exposed to light such as sunlight. As a renewable power source, PV panels are becoming increasingly popular. PV systems generally include power converters to convert the power produced by PV panels to power suitable for transmission to a load, and energy storage devices that enable the PV system to provide power when little or no sunlight is present. Generally, larger PV systems require more of these associated components, which increases the cost of the PV system in terms of material, electrical complexity, and space. Additionally, PV panels generally operate more efficiently at a certain temperature range, and may benefit from cooling systems that prevent the PV panels from overheating. A modular PV system is therefore desirable.BRIEF DESCRIPTION

[0003] In one aspect, a power generation device is provided. The power generating device includes a photovoltaic panel configured to generate a first type of electrical power. The power generating device further includes a power converter electrically coupled to the photovoltaic panel and configured to convert the first ty pe of electrical poyver to a second type of electrical power for transmission to a grid and / or load. The poyver generating device further includes at least one energy storage device electrically coupled to the poyver converter, the at least one energy storage device configured to store electrical energy provided by the poyver converter. The poyver generating device further includes at least one heat management component and at least one back housing physically attached to the photovoltaic panel and defining a space between the photovoltaic panel and the at least one back housing. The power converter, the at least one energy storage device, and the atleast one heat management component are positioned in the space between the photovoltaic panel and the at least one back housing.

[0004] In another aspect, a method for manufacturing a power generation device is provided. The method includes electrically coupling a photovoltaic panel configured to generate a first type of electrical power to a power converter configured to convert the first ty pe of electrical power to a second type of electrical power for transmission to a grid and / or load. The method further includes electrically coupling at least one energy storage device to the power converter, the at least one energy storage device configured to store electrical energy provided by the power converter. The method further includes physically attaching at least one back housing to the photovoltaic panel to define a space between the photovoltaic panel and the at least one back housing, wherein the power converter, the at least one energy storage device, and at least one heat management component are positioned in the space between the photovoltaic panel and the at least one back housing.

[0005] In another aspect, a grid-independent power system is provided. The grid-independent power system includes a load and a power generation device. The power generation device includes a photovoltaic panel configured to generate a first type of electrical pow er. The power generation device further includes a pow er converter electrically coupled to the photovoltaic panel and configured to convert the first type of electrical power to a second type of electrical pow er for transmission to the load. The power generating device further includes at least one energy storage device electrically coupled to the powder converter, the at least one energy storage device configured to store electrical energy provided by the power converter. The power generating device further includes at least one heat management component and at least one back housing physically attached to the photovoltaic panel and defining a space between the photovoltaic panel and the at least one back housing. The pow er converter, the at least one energy' storage device, and the at least one heat management component are positioned in the space between the photovoltaic panel and the at least one back housing.DRAWINGS

[0006] These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

[0007] FIG. 1 depicts an exploded view of example power generation device.

[0008] FIG. 2 is a diagram of an example power generation system including the power generation device shown in FIG. 1.

[0009] FIG. 3 is a cross-sectional diagram of the pow er generation device shown in FIG. 1.

[0010] FIG. 4 is a graph illustrating a relationship between time of day, temperature, and PV efficiency for an example power generation device.

[0011] FIG. 5 is a flowchart of an example method for manufacturing a power generation device.DETAILED DESCRIPTION

[0012] In the following specification and the claims, reference will be made to a number of terms, which shall be defined to have the following meanings.

[0013] The singular forms “a,” “an / ’ and “the” include plural references unless the context clearly dictates otherwise.

[0014] Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about,” “substantially,” and “approximately,” are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument formeasuring the value. Here and throughout the specification and claims, range limitations may be combined and / or interchanged, such ranges are identified and include all the subranges contained therein unless context or language indicates otherwise.

[0015] The embodiments described herein include a power generation device including a PV panel configured to generate a first type of electrical power such as direct current (DC) power. The power generation device further includes a power converter physically attached to and electrically coupled to the PV panel and configured to convert the first type of electrical power to a second type of electrical power, such as alternating current (AC) power, for transmission to a grid and / or load. The power generation device further includes at least one energy storage device physically attached to the PV panel and electrically coupled to the power converter. The energy storage device is configured to store electrical energy that is generated by the PV panel and provided to the energy storage device by the power converter. In some embodiments, the power generation device further includes a housing that, with the PV panel, defines an enclosure that contains the power converter and energy storage device.

[0016] Because the PV panel, power converter, and energy storage device are integrated into one package, the disclosed power generation devices are easy to deploy (e.g., as plug-and-play devices) and do not require separate, external power converters, energy storage devices, or other associated infrastructure, such as racks and heating, ventilation, and air conditioning (HVAC) systems. The disclosed power generation device is therefore particularly suitable in relatively small-scale applications and / or remote applications in which a connection to the grid may not be practical. For example, the power generation device can be used to implement a grid-independent power system to supply power for remote applications such as, for example, community microgrids, deployable energy (e.g., combat support or other mobile hospitals), remote airports, and / or off-grid electric vehicle charging or for other remote devices. Further, because the power converters and energy storage devices are self-contained within the power generation device, any grid or microgrid including the disclosed power generation devices has energy storage distributed among the power generation devices, reducing a need for larger and more expensive standalone energy storage systems and associated power conversion systems.

[0017] In some embodiments, the disclosed power generation device further includes a cooling system, such as a heat sink, phase change material, heat fins, heat pipes, or any combination thereof, which is configured to cool and / or maintain a relatively constant temperature of the PV panel throughout the day. Because PV panels generally operate more efficiently at a specific temperature (e.g., as opposed to a higher temperature), the cooling system enable the PV panel to operate more efficiently on average. In some cases, the cooling system may reduce a peak daytime temperature of the PV panel by about 40 degrees Celsius, and may improve an efficiency of the PV panel by about 30 percent. Further, by reducing temperature vanation of the PV panel and other components of the power generation device, the cooling system reduces wear and tear due to heat, potentially prolonging a lifetime of the power generation device and reducing maintenance costs.

[0018] FIG. 1 is an exploded view of an example power generation device 100. In the example embodiment, power generation device 100 includes a PV panel 102, a power converter 104, an energy storage device 106, and back housing 108. In some embodiments, power generation device 100 further includes a heat management component 110 and a heat spreader 112.

[0019] In the example embodiments, PV panel 102 is configured to generate a first type of electrical power, such as DC power. As shown in FIG. 1, PV panel 102 and back housing 108 together form an internal space to contain power converter 104, energy storage device 106, heat management component 110, and heat spreader 112.

[0020] In the example embodiment, power converter 104 is physically attached to and electrically coupled to PV panel 102 and is configured to convert the first type of electrical power output by PV panel 102 to a second type of electrical power for transmission to a grid and / or load. In certain embodiments, power converter 104 includes silicon, silicon carbide, and / or gallium nitride power devices, and / or power devices constructed from any other suitable semiconductor material.

[0021] As described in further detail below, power converter 104 may convert DC power to AC power to transmit to the grid and / or load. Accordingly, power converter 104 enables power generation device 100, in some circumstances, to be coupled directly to a grid without a need for any intervening power conversion circuitry. For thisreason, the system is scalable down to relatively small sizes without a potentially high overhead cost of such circuitry. For example, one or a small number of power generation devices 100 may be installed in a home or business. In various example embodiments, power generation devices 100 can be ground-mounted, roof-mounted, installed above and / or floating on bodies of w ater such as lakes, or in other locations. In another example, multiple power generation devices 100 can be used in parallel, in a single location or remotely, to form a virtual power plant.

[0022] In the example embodiments, energy storage device 106 is also physically attached to PV panel 102, and is electrically coupled to power converter 104. Energy storage device 106 is configured to store electrical energy7provided by power converter 104, enabling energy storage device to store energy when, for example, enough solar radiation is present for PV panel 102 to produce more power than is required by the load, and to discharge to provide power when demanded. Examples of energy storage devices 106 include lithium-ion cells of vary ing chemistries including, but not limited to, nickel manganese cobalt, lithium iron phosphate, or other non-flammable lithium-ion battery7types, solid state batteries, capacitors, or combinations thereof. The energy storage devices 106 may include, but are not limited to, pouch, prismatic, can types, or combinations thereof.

[0023] In the example embodiment, heat management component 110 is physically attached to and in thermal communication with PV panel 102. Heat management component 110 is configured to reduce an average temperature of PV panel 102 by accumulating heat when PV panel 102 is hot (e.g., during the day) and dissipating the heat to the surrounding environment when temperatures have cooled (e.g., at night), as well as reducing a transfer of heat between PV panel 102 and internal components of power generation device 100 such as power converter 104 and energy storage device 106. In some embodiments, heat management component 110 includes a phase change material (e.g., paraffin, pure hydrocarbons, molten salts, eutectic alloys, etc.) that undergoes a phase change (e.g., melting from a solid to a liquid or freezing from a liquid to a solid) while within a normal operating temperature range of PV panel 102. During such phase changes, a temperature of the phase change material remains constant even as the surrounding environment becomes warmer, enabling heat management component 110 to efficiently cool PV panel 102 and other components of power generation device 100. In some embodiments,heat management component 1 10 includes insulation, heat sinks, and / or other materials or devices for managing a transfer of heat throughout power generation device 100. Heat spreader 112 enables heat to be transported to and from the heat management component 110 efficiently and dissipated from heat management component 110, for example, though back housing 108. In some embodiments, back housing 108, heat management component 110, and / or heat spreader 112 includes fins and / or heat pipes to enhance dissipation of heat.

[0024] FIG. 2 is a diagram showing an electrical architecture of power generation device 100 showing additional detail of power converter 104. As shown in FIG. 2, in the example embodiment, power converter 104 includes a controller 202, an inverter 204, a transformer 206, and a DC to DC converter 208. Inverter 204 is configured to convert DC power output by PV panel 102 or energy storage device 106 to AC power for transmission to the grid and / or load. Transformer 206 is electrically coupled between inverter 204 and the grid and / or load and is configured to convert the AC power output by inverter 204 to a voltage appropriate for the grid and / or load. In some embodiments, inverter 204 is a grid forming inverter (GFM) that can transition seamlessly from grid-present to no-grid operation.

[0025] DC to DC converter 208 is electrically coupled to energy storage device 106. DC to DC converter 208 is configured to convert DC electrical power output by PV panel 102 at a first voltage to DC power having another voltage for supplying to energy storage device 106, and to convert DC power output by energy storage device to DC power having the first voltage.

[0026] Controller 202 is configured to control inverter 204 and DC to DC converter 208 based on sensor data (e.g., a measured voltage at PV panel 102 and / or the grid and / or load), external commands, and other data. For example, as described above, controller 202 may control inverter 204 and DC to DC converter 208 to send excess PV power to the grid, to send excess PV power to energy storage device 106 for charging, or to curtail in case energy storage device 106 is fully charged, loads are insufficient, and / or the grid is not present.

[0027] FIG. 3 is a cross-sectional diagram of power generating device 100. As shown in FIG. 3, power generation device 100 includes a support structure 302 disposed between PV panel 102 and back housing 108 and configured to support the internal components of power generation device 100 within the space between PV panel 102 and back housing 108. In some embodiments, support structure 302 may be structurally integrated with PV panel 102, back housing 108, and / or heat management component 110. In some embodiments, support structure 302 includes insulation.

[0028] As shown in FIG. 3, in some embodiments, heat management component 110 is divided into a plurality of sections contained within respective compartments of support structure 302. Each of these sections of heat management component 110 is in thermal communication with and configured to cool or manage a temperature of a respective component of power generation device 100 (e.g., partially or completely covering the component). For example, as shown in FIG. 3, PV panel 102, energy storage device 106, controller 202, inverter 204, and DC to DC converter 208 may each have respective sections of heat management component 110 thermally coupled thereto. In some embodiments, each of these sections may include a different type of phase change material with thermal characteristics (e.g., melting point) selected to be appropriate for the corresponding component. One or more of these sections also interface with one or more sections of back housing 108 to facilitate dissipation of heat through back housing 108 into the ambient environment and to serve as an protective cover for the enclosed components from water, dust, or other contaminants. Back housing 108 may include fins 304 or other extended surfaces of different shapes and profiles, or be coated with a spectral film, to facilitate this transfer of heat. In some embodiments, back housing 108 and support structure 302 may be formed from metal, plastic, conductive plastic, and / or plastic with thermally conductive fillers.

[0029] In some embodiments, power generation device 100 is configured to be tilted or otherwise reoriented to facilitate heat management of power generation device 100. For example, during the day, power generation device 100 may be oriented with PV panel 102 upward or facing the sun so that PV panel 102 may generate power. During this time, heat management component 110 may absorb heat so that a reduced or constant temperature is maintained in PV panel 102, energy storage device 106, and other componentsof power generation device 100. At night, power generation device 100 may be tilted so that back housing 108 is oriented upward, to enhance dissipation of heat to the surrounding environment. In some embodiments, additional electric power may be generated at this time using a space coupled thermo-electric generator or other device capable of converting heat energy stored in back housing 108 and / or heat management component 110 to electric power. In certain embodiments, power generation device 100 is installed on a tracker that can track the sun during the day (e g., over one or more axes) so that power generation device 100 can be oriented toward the sun.

[0030] In some embodiments, power generation device 100 includes and / or is covered in a spectral film that is opaque to certain wavelengths of radiation. This spectral film may allow light that PV panel 102 can use to generate electric power through while radiating thermal energy back to the outer surroundings, thereby reducing heating of power generation device 100. The spectral film may further allow longer wavelengths of radiation through, enabling heat to radiate from power generation device 100 at night. A thermal emissivity of PV panel 102 and / or back housing 108 and size or thickness of heat management components 110 can also be selected to enhance dissipation of heat from power generation device 100.

[0031] FIG. 4 is a graph 400 illustrating a temperature and energy PV efficiency of two example PV panels over the course of a day. PV efficiency refers to the percentage of energy in the form of light that can be converted into electrical energy by the PV panel. Graph 400 includes a horizontal axis 402 representing time of day expressed in hours. Graph 400 further includes a first vertical axis 404 representing temperature expressed in degrees Celsius. Graph 400 further includes a second vertical axis 406 representing PV efficiency.

[0032] Graph 400 includes a first temperature curve 408 and first PV efficiency curve 410 corresponding to a first PV panel having no cooling system, and a second temperature curve 412 and a second PV efficiency curve corresponding to a second PV panel having a cooling system similar to that illustrated in FIG. 1 with respect to power generating device 100. As shown in graph 400, a temperature of the first PV panel (shown by first temperature curve 408) increases during the day. As the temperature increases a corresponding PV efficiency (shown by first PV efficiency curve 410) decreases. In contrast,a temperature of the second panel (shown by second temperature curve 412) remains relatively constant throughout the day, and accordingly, the PV efficiency of the second PV panel (shown by second PV efficiency curve 414) remains relatively constant.

[0033] FIG. 5 is a flowchart illustrating an example method 500 for manufacturing a power generation system such as power generation device 100 (shown in FIGS. 1 and 2).

[0034] In the example embodiment, method 500 includes electrically coupling 502 a photovoltaic panel (such as PV panel 102) configured to generate a first type of electrical power to a pow er converter (such as pow er converter 104) configured to convert the first type of electrical power to a second type of electrical power for transmission to a grid and / or load.

[0035] In the example embodiment, method 500 further includes electrically coupling 504 at least one energy storage device (such as energy storage device 106) to the power converter. The energy storage device is configured to store electrical energy provided by the power converter.

[0036] In the example embodiment, method 500 further includes physically attaching 506 a back housing (such as back housing 108) to the photovoltaic panel to define a space therebetween, wherein the power converter, the at least one energy storage device, and at least one heat management component (such as heat management component (such as heat management component 110) are positioned in the space between the photovoltaic panel and the back cover.

[0037] In some embodiments, the heat management component reduces an average temperature of the photovoltaic panel.

[0038] In some embodiments, the heat management component includes a phase change material.

[0039] In some such embodiments, the phase change material includes a plurality of sections, and each section of the plurality of sections is thermally coupled to one of the photovoltaic panel, the power converter, and / or the at least one energy storage device.

[0040] In some embodiments, the heat management component includes insulation.

[0041] In some embodiments, the back housing includes a heat sink.

[0042] In some such embodiments, the heat sink includes heat pipes and / or fins.

[0043] In some embodiments, the first type of electrical power is DC power and the second type of electrical power is AC power, and the power converter includes an inverter (such as inverter 204) configured to convert the DC power to the AC power.

[0044] In some embodiments, the first type of electrical power is DC power having a first voltage, the power converter further includes a DC to DC converter (such as DC to DC converter 208) configured to convert the first type of electrical power to a third type of electrical power to charge the at least one energy storage device, and the third type of electrical power is DC power having a second voltage different from the first voltage.

[0045] In some embodiments, the DC to DC converter is further configured to convert DC power received from the at least one energy storage device and having the second voltage to DC power having the first voltage.

[0046] In some embodiments, method 500 further includes electrically coupling the power converter to the grid and / or load via a transformer (such as transformer 206).

[0047] In some embodiments, one or more of the photovoltaic panel and / or the back housing are attached to a spectral film.

[0048] An example technical effect of the methods, systems, and apparatus described herein includes at least one of: (a) plug-and-play capability for a PV power generation device by incorporating a PV panel, power converter, and energy storage into a single package; (b) reduced costs associated with a PV power generation system by including power conversion and energy storage capabilities distributed among individual PV devices rather than centralized power conversion and energy7storage; and / or (c) improved coolingPV efficiency and energy efficiency by incorporating a heat sink and / or other cooling components into a PV power generation device.

[0049] Example embodiments of a power generation device are provided herein. The systems and methods are not limited to the specific embodiments described herein, but rather, components of systems and / or steps of the methods may be utilized independently and separately from other components and / or steps described herein. For example, the methods may also be used in combination with other electronic systems, and are not limited to practice with only the electronic systems, and methods as described herein. Rather, the example embodiments can be implemented and utilized in connection with many other electronic systems.

[0050] Some embodiments involve the use of one or more electronic or computing devices. Such devices typically include a processor, processing device, or controller, such as a general purpose central processing unit (CPU), a graphics processing unit (GPU), a microcontroller, a reduced instruction set computer (RISC) processor, an application specific integrated circuit (ASIC), a programmable logic controller (PLC). a field programmable gate array (FPGA), a digital signal processing (DSP) device, and / or any other circuit or processing device capable of executing the functions described herein. The methods described herein may be encoded as executable instructions embodied in a computer readable medium, including, without limitation, a storage device and / or a memory device. Such instructions, when executed by a processing device, cause the processing device to perform at least a portion of the methods described herein. The above embodiments are examples only, and thus are not intended to limit in any way the definition and / or meaning of the term processor and processing device.

[0051] Although specific features of various embodiments of the disclosure may be shown in some drawings and not in others, this is for convenience only. In accordance with the principles of the disclosure, any feature of a drawing may be referenced and / or claimed in combination with any feature of any other drawing.

[0052] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing anyincorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.

Claims

WHAT IS CLAIMED IS:

1. A power generation device comprising: a photovoltaic panel configured to generate a first type of electrical power; a power converter electrically coupled to said photovoltaic panel and configured to convert the first type of electrical power to a second type of electrical power for transmission to a grid and / or load; at least one energy storage device electrically coupled to said power converter, said at least one energy storage device configured to store electrical energy provided by said power converter; at least one heat management component; and at least one back housing physically attached to said photovoltaic panel and defining a space between said photovoltaic panel and said at least one back housing, wherein said power converter, said at least one energy storage device, and said at least one heat management component are positioned in the space between said photovoltaic panel and said at least one back housing.

2. The power generation device of Claim 1, wherein said at least one heat management component facilitates reducing an average temperature of said photovoltaic panel.

3. The power generation device of Claim 1, wherein said at least one heat management component comprises a phase change material.

4. The power generation device of Claim 3, wherein said phase change material comprises a plurality of sections, each section of said plurality of sections thermally coupled to one of said photovoltaic panel, said power converter, and / or said at least one energy storage device.

5. The power generation device of Claim 1, wherein said at least one heat management component comprises insulation.

6. The power generation device of Claim 1 , wherein said at least one back housing comprises a heat sink.

7. The power generation device of Claim 6, wherein said heat sink comprises heat pipes and / or fins.

8. The power generation device of Claim 1, wherein the first type of electrical power is direct current (DC) power and the second type of electrical power is alternating cunent (AC) power, and wherein said power converter comprises an inverter configured to convert the DC power to the AC power.

9. The power generation device of Claim 1. wherein the first type of electrical power is DC power having a first voltage, wherein said power converter further comprises a DC to DC converter configured to convert the first ty pe of electrical power to a third type of electrical power to charge said at least one energy storage device, and wherein the third type of electrical power is DC power having a second voltage different from the first voltage.

10. The power generation device of Claim 9, wherein said DC to DC converter is further configured to convert DC power received from said at least one energy storage device and having the second voltage to DC power having the first voltage.

11. The power generation device of Claim 1, wherein said power converter is electrically coupled to the grid and / or load via a transformer.

12. The power generation device of Claim 1, wherein one or more of said photovoltaic panel and / or said back housing are attached to a spectral film.

13. A method for manufacturing a power generation device, said method comprising: electrically coupling a photovoltaic panel configured to generate a first t pe of electrical power to a power converter configured to convert the first type of electrical power to a second type of electrical power for transmission to a grid and / or load;electrically coupling at least one energy storage device to the power converter, the at least one energy storage device configured to store electrical energy provided by the power converter; and physically attaching at least one back housing to the photovoltaic panel to define a space between the photovoltaic panel and the at least one back housing, wherein the power converter, the at least one energy storage device, and at least one heat management component are positioned in the space between the photovoltaic panel and the at least one back housing.

14. The method of Claim 13, wherein the at least one heat management component facilitates reducing an average temperature of the photovoltaic panel.

15. The method of Claim 13, wherein the at least one heat management component includes a phase change material.

16. The method of Claim 15, wherein the phase change material includes a plurality of sections, and wherein each section of the plurality of sections is thermally coupled to one of the photovoltaic panel, the power converter, and / or the at least one energy storage device.

17. The method of Claim 13, wherein the at least one heat management component includes insulation.

18. The method of Claim 13, wherein the at least one back housing includes a heat sink.

19. The method of Claim 18, wherein the heat sink includes heat pipes and / or fins.

20. A grid-independent power system comprising: a load; and a power generation device comprising:a photovoltaic panel configured to generate a first type of electrical power; a power converter electrically coupled to said photovoltaic panel and configured to convert the first type of electrical power to a second type of electrical power for transmission to said load; at least one energy storage device electrically coupled to said power converter, said at least one energy storage device configured to store electrical energy provided by said power converter; at least one heat management component; and at least one back housing physically attached to said photovoltaic panel and defining a space between said photovoltaic panel and said at least one back housing, wherein said power converter, said at least one energy storage device, and said at least one heat management component are positioned in the space between said photovoltaic panel and said at least one back housing.

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