Solar Power Production and Metering
Systems and methods for positioning photovoltaic panels above agricultural land are disclosed. The photovoltaic panels can be suspended over agricultural land and supported by vertical holders, which are generally arranged in a two-dimensional grid. Sufficient clearance exists between the base surface and the photovoltaic panels for the operators and the agricultural machinery. The position of the photovoltaic panels can be adjusted using panel orientation systems. A decision about the photovoltaic panel angle with respect to the incoming sunlight can be based on the insolation/shade needs of the agricultural plants beneath the system and also on the need to generate electrical energy by insolating the panels. Furthermore, the systems and methods can be used for a net metering of energy. An energy ratepayer who is also a sole or fractional owner of the renewable energy production capacity can subtract the energy production from the energy consumption, thus resulting in the net metering of energy.
The present invention relates generally to solar, wind or other renewable energy production. More particularly, the renewable energy is produced in conjunction with harvestable plant production on agricultural land. The renewable energy produced can be used to offset the renewable energy consumed at a ratepayer's residence or business, thus resulting in a net energy metering.
Due to the concerns over global warming and the limited amount of fossil fuels, alternative methods of energy production are desired. Such alternative sources of energy are solar energy produced by photovoltaic solar panels, which utilize the photoelectric effect to convert the energy of sun's radiation into electricity, wind energy that is converted to the electrical energy by wind turbines and electrical generators, or other renewable sources of energy.
While the average solar power density reaching Earth is 1.3 kW/m2 to 1.4 kW/m2, depending on the time of year, the local solar power density can vary greatly depending on the presence of clouds, flatness of the area, presence of tall natural or manmade objects, and the orientation of the base surface with respect to the incoming sunlight. Thus, flat, cloudless deserts receive more insolation per unit area than some cloudy and hilly areas. Furthermore, for better economies of scale it is preferred to install a large number of photovoltaic panels in a common location, because the panel mounting infrastructure, transmission lines, maintenance, and metering can be shared by the collocated photovoltaic panels. While sizeable areas of flat and mostly cloudless land are available in many desert regions, such regions are often far away from the urban locations, where most of the energy is ultimately consumed. Suitable electrical transmission lines extending from the desert regions to the urban regions do not exist in many cases. Constructing the electrical transmission lines can cost up to $3,000,000 per mile according to some estimates, depending on the required capacity of the transmission lines and the type of the terrain where the transmission lines are installed. Furthermore, excessive temperatures and sand erosion in the deserts can reduce the conversion efficiency and shorten the lifespan of the photovoltaic panels, resulting in a more expensive renewable energy. On the other hand, there are many areas with a desirable combination of insolation, pre-existing transmission lines, and proximity to urban zones, but those areas are already in use as the agricultural land. The production of electricity by photovoltaic panels should preferably not degrade the agricultural value of the land in order not to reduce the profits that are derived from such a land. Therefore, a need exists for systems and methods that can be used in the photovoltaic production of the electricity, while not impeding, and possibly even improving, the agricultural utility of the land where the systems are installed.
Furthermore, renewable energy that is produced at a remote location, for example, an energy installation collocated with a farm or a ranch, can be owned by a single entity or fractionally, meaning that multiple owners have rights to a certain fraction of the energy produced. For example, each fractional owner may have rights to the energy produced by a certain number of the photovoltaic panels. When electricity is produced close to the ratepayer's site, that electricity may be fed directly to the ratepayer without using a common utility distribution grid. If the ratepayer produces more energy than he or she needs, the excess is transferred to the common utility distribution grid, and further to other ratepayers on the grid. Some existing methods and devices use electrical meters that, essentially, spin backwards when energy is delivered from the ratepayer's site to the common utility grid, thus reducing the renewable energy producer's total electricity bill. However, these methods and devices are only practicable for energy production sites that are collocated with or close to the respective energy consumption sites.
Whether the energy is produced close or remote to the ratepayer's site, the energy can be delivered to the shared electrical grid, wherefrom it can be transported to any ratepayer connected to the grid. Some existing methods and devices measure the energy produced at the production site, and send an itemized, per-fractional-owner accounting to a public utility, which also receives an accounting of the energy used by the ratepayers at their residences or businesses. The public utility then subtracts the electrical energy produced by a given ratepayer from the energy consumed by the same ratepayer, thus arriving at a net energy accounting that the ratepayer will be charged for. However, with this method the burden of the accounting paperwork and reconciling the ratepayer's produced vs. consumed energy is shifted to the public utility.
Therefore, a need remains for systems and methods that can provide a simple net energy accounting and billing, without burdening the public utilities with additional billing and paperwork.
BRIEF SUMMARY OF THE INVENTIONThe present invention relates to systems and methods for positioning photovoltaic panels above agricultural land. The photovoltaic panels can be supported by vertical holders, which are generally arranged in a two-dimensional grid over a base surface that is used as the agricultural land. Sufficient clearance can be left between the base surface and the photovoltaic panels for the operators and the agricultural machinery. The position of the photovoltaic panels can be adjusted using panel orientation apparatuses. A decision about the photovoltaic panel angle with respect to the incoming sunlight can be based on the insolation/shade needs of the agricultural plants beneath the system and also on the need to generate electrical energy by insolating the photovoltaic panels. Furthermore, the systems and methods in accordance with the embodiments of the present invention can be used for a net metering of energy. An energy ratepayer who is also a sole or fractional owner of the renewable energy production capacity can subtract the energy production from the energy consumption, thus resulting in the net metering of energy. The electricity can be provided to the power grid, while an energy production report can be sent from the energy production site to the ratepayer's metering device, which then performs the required processing to calculate the net energy report. The calculated net energy report can be sent to the public utility, which charges the ratepayer only for the net energy used, while avoiding the overhead and paperwork required for the net energy accounting. The existing power grid or wireless devices can be used to transfer the energy production report to the metering device and the net energy report to the public utility. Additionally, the value of the renewable energy, sent either directly to the end users or to the common power grid, can be adjusted to reflect a price premium placed on the renewable energy in comparison with the energy produced by traditional sources.
In one embodiment, an apparatus for controlling the orientation of photovoltaic panels has: a generally horizontal platform mounted on one or more generally vertical supports, the supports being configured and dimensioned to elevate the platform such as to allow clearance for the agricultural machinery and/or personnel between the platform and a base surface; one or more holders attached with the platform, the holders being configured and dimensioned for pivotably holding the photovoltaic panels; and first orientation means configured to pivot the photovoltaic panels in response to a control signal thus changing a shading on the base surface below the platform, where the control signal is determined at least in part based on the insolation data and plant growth cycle data.
In one aspect, the insolation data contains solar intensity and/or direction of solar radiation.
In another aspect, the plant growth cycle data contains temperature, humidity, light, available nutrients in the soil, and plant age.
In another aspect, the apparatus has one or more frames that extend about a longitudinal axis, the frames being tiltably mounted to the platform and configured and dimensioned for holding the photovoltaic panels parallel to one another, and second orientation means that are configured to adjust a tilt angle of the frames, thus adjusting the tilt angle of the photovoltaic panels held by the holders along the longitudinal axis of the frames.
In another aspect, the apparatus has an energy measuring device configured to measure electrical energy production by the photovoltaic panels and configured to generate an energy production report representative of the energy produced by one or more photovoltaic panels associated with a ratepayer; means for sending the energy production report to a local metering device located locally with the ratepayer; the local metering device being configured to: receive the energy production report from the remotely located energy production facility, measure the energy consumption of the ratepayer, process the energy production report with the energy consumption of the ratepayer to determine a net energy consumption report; and means for sending the net energy consumption report to a utility company.
In another embodiment, a method for controlling the orientation of the photovoltaic panels includes: receiving the insolation data containing solar intensity and/or angle of solar radiation; receiving plant growth cycle data; determining a position of the photovoltaic panel based on the insolation data and/or plant growth cycle; and orienting the photovoltaic panels to the position, where the position of the photovoltaic panels is configured such as to result in a predetermined percentage of a base surface below the photovoltaic panels being shaded.
In one aspect, the method includes: associating at least a portion of the remotely located energy production facility with a ratepayer; generating an energy production report representative of the renewable energy produced at the remotely located energy production facility and associated with the ratepayer; sending the energy production report to a local metering device located locally with the ratepayer, where the local metering device is configured to receive the energy production report and where the local metering device is configured to measure the energy consumption of the ratepayer; receiving the energy production report sent from the remotely located energy production facility at the local metering device; and using the local metering device for processing the energy production report with the energy consumption of the ratepayer to determine a net energy consumption report.
In yet another aspect, the method includes sending the energy production report wirelessly or over an existing power grid to the local metering device.
For a further understanding of the nature and advantages of the invention, reference should be made to the following description taken in conjunction with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the embodiments of the present invention.
The present invention relates to systems and methods for positioning photovoltaic panels above agricultural land. The photovoltaic panels can be supported by vertical holders, which are generally arranged in a two-dimensional grid over a base surface that is used as the agricultural land. Sufficient clearance can be left between the base surface and the photovoltaic panels for the operators and the agricultural machinery. The position of the photovoltaic panels can be adjusted using panel orientation systems. A decision about the photovoltaic panel's angle with respect to the incoming sunlight can be based on the insolation/shade needs of the agricultural plants beneath the system and also on the need to generate electrical energy by insolating the photovoltaic panels. Furthermore, systems and methods can be used for a net metering of energy. An energy ratepayer who is also a sole or fractional owner of the renewable energy production capacity can subtract the energy production from the energy consumption, thus resulting in the net metering of energy. The electricity can be provided to the power grid, while an energy production report can be sent from the energy production site to the ratepayer's metering device, which then performs the required processing to calculate the net energy report. The calculated net energy report can be sent to the public utility, which charges the ratepayer only for the net energy used, while avoiding the overhead and paperwork required for the net energy accounting. The existing power grid or wireless devices can be used to transfer the energy production report to the metering device and the net energy report to the public utility. Additionally, the value of the renewable energy, sent either directly to the end users or to the common power grid, can be adjusted to reflect a price premium placed on the renewable energy in comparison with the energy produced by traditional sources.
Shaded %=L sin(α+β)/D sin(α) Eq. (1)
Different combinations of L, D, α, and β will result in different percentages of the base surface being either insolated or in the shade, as explained in more detail below in reference with
The above described photovoltaic panel positioning apparatuses can be used in conjunction with the net metering of energy described below.
Still describing the embodiment illustrated in
As will be understood by those skilled in the art, the present invention may be embodied in other specific forms without departing from the essential characteristics thereof. For example, the photovoltaic panels do not necessarily have to be parallel to each other over the entire positioning mechanism. The positioning mechanism may subdivide the photovoltaic panels into zones of different panel orientation, resulting in different electrical energy production and shading in the zones. A business entity may provide hosting, maintenance, cleaning, metering, and accounting for a group of fractional owners. Such a business entity may provide a real-time energy production information for the fractional owners, over the internet or otherwise. Furthermore, the net energy metering can be used for green credit or green rebate accounting by, for example, sending the net energy report or the renewable energy production report to green credit or green rebate accounting entities. Wealthy individuals may assign their fractional ownership or produced energy to a cause they want to support, like, for example, a school, a pet hospital, or an opera house. A donation of renewably energy may be left in a will. Many other embodiments are possible without deviating from the spirit and scope of the invention. These other embodiments are intended to be included within the scope of the present invention, which is set forth in the following claims.
Claims
1. An apparatus for controlling the orientation of photovoltaic panels, comprising:
- a generally horizontal platform mounted on one or more generally vertical supports, said supports configured and dimensioned to elevate the platform such as to allow clearance for agricultural machinery and/or personnel between the platform and a base surface;
- one or more holders attached with the platform, said holders configured and dimensioned for pivotably holding the photovoltaic panels; and
- first orientation means configured to pivot the photovoltaic panels in response to a control signal thus changing a shading on the base surface below the platform, wherein said control signal is determined at least in part based on insolation data and plant growth cycle data.
2. The apparatus of claim 1, wherein said insolation data comprises solar intensity and/or direction of solar radiation.
3. The apparatus of claim 1, wherein said plant growth cycle data comprise temperature, humidity, light, available nutrients in the soil, and plant age.
4. The apparatus of claim 2, further comprising a measurement device configured to measure intensity and direction of the solar radiation.
5. The apparatus of claim 1, wherein:
- said platform is mounted substantially over at least one greenhouse, and
- said supports comprise parts of said at least one greenhouse.
6. The apparatus of claim 5, wherein said control signal is determined at least in part based on the ventilation of the greenhouse by pivoting the photovoltaic panels.
7. The apparatus of claim 1, further comprising:
- one or more frames extending about a longitudinal axis, said frames tiltably mounted to the platform and configured and dimensioned for holding the photovoltaic panels parallel to one another, and
- second orientation means configured to adjust a tilt angle of said frames, thus adjusting the tilt angle of the photovoltaic panels held by the holders along the longitudinal axis of the frames.
8. The apparatus of claim 7, wherein said first orientation means adjust the pivot angle of the photovoltaic panels in all the frames to substantially the same value.
9. The apparatus of claim 7, wherein said second orientation means adjust the tilt angle of all the frames to substantially the same value.
10. The apparatus of claim 7, wherein said frames are tilted about an axis passing through the frame and being substantially parallel to the base surface.
11. The apparatus of claim 1, wherein said control signal is determined based on pre-programmed data about the position of Sun relative to latitudinal and longitudinal position of the apparatus.
12. The apparatus of claim 1, further comprising a generally horizontal service platform attached with the holders and disposed between the photovoltaic panels and the base surface, said service platform configured and dimensioned to carry an operator and/or a sprinkler system.
13. The apparatus of claim 1, wherein said service platform is disposed above the photovoltaic panels.
14. The apparatus of claim 1, further comprising an energy metering device configured to measure energy produced by said photovoltaic panels.
15. The apparatus of claim 14, wherein said energy metering device is configured to measure energy produced by an individual photovoltaic panel or by a group of the photovoltaic panels.
16. The apparatus of claim 1, further comprising:
- an energy measuring device configured to measure the electrical energy production by the photovoltaic panels and to generate an energy production report representative of the energy produced by one or more photovoltaic panels associated with a ratepayer;
- means for sending the energy production report to a local metering device located locally with the ratepayer;
- the local metering device configured to: receive the energy production report from the remotely located energy production facility, measure the energy consumption of the ratepayer, process the energy production report with the energy consumption of the ratepayer to determine a net energy consumption report; and
- means for sending the net energy consumption report to a utility company.
17. The apparatus of claim 16, wherein said means for sending the energy production report to the metering device operate wirelessly or over an existing power grid.
18. The apparatus of claim 16, wherein said means for sending the net energy consumption report to a utility company operate wirelessly or over an existing power grid.
19. The apparatus of claim 16, further comprising means for sending the net energy consumption report to a green credit accounting entity for assigning a green credit to said customer.
20. The apparatus of claim 16, further comprising means for sending the net energy consumption report to an accounting entity for calculating a green rebate.
21. The apparatus of claim 1, further comprising:
- a master green meter configured to: measure the electrical energy production by the photovoltaic panels, generate an energy production report representative of the energy produced by the photovoltaic panels, and transmit the energy production report to a utility company,
- wherein the utility company assigns a value to the energy produced by the photovoltaic panels and delivers the energy to the end users using a common power grid.
22. The apparatus of claim 1, further comprising:
- at least one energy measuring device configured to measure the electrical energy produced by one or more photovoltaic panels, and
- a control computer in communication with said energy measuring devices, said control computer configured to collect the measurement data from said energy measuring devices and to transmit said measurement data and a fractional owner identification to a utility company,
- wherein the utility company assigns a value to the energy produced by the photovoltaic panels and delivers the energy to end users.
23. The apparatus of claim 22, wherein said end users are chosen in accordance with the fractional owners instructions.
24. The apparatus of claim 1, further comprising:
- transmission means for delivering the electrical energy produced by the photovoltaic panels to at least one end user, and
- at least one green metering device assigned to said at least one end user, said at least one metering device configured to: meter the electrical energy produced by the photovoltaic panels and delivered to said at least one end user, and transmit metered values to the utility company.
25. A method for controlling the orientation of photovoltaic panels, comprising:
- receiving insolation data comprising solar intensity and/or angle of solar radiation;
- receiving plant growth cycle data;
- determining a position of the photovoltaic panel based on the insolation data and/or plant growth cycle; and
- orienting the photovoltaic panels to the position, said position of the photovoltaic panels configured such as to result in a predetermined percentage of a base surface below the photovoltaic panels being shaded.
26. The method of claim 25, wherein said plant growth cycle data comprise temperature, humidity, light, available nutrients in the soil, and plant age.
27. The method of claim 25, wherein said determining is based at least in part on the cost of electrical energy.
28. The method of claim 25, further comprising reading a temperature of the surface below the photovoltaic panels, wherein the determining the position of the photovoltaic panel is based at least in part on said temperature of the surface below the photovoltaic panels.
29. The method of claim 25, wherein said photovoltaic panels are configured over at least one greenhouse, and wherein said determining is based at least in part on a ventilation of said at least one greenhouse.
30. The method of claim 25, further comprising:
- associating at least a portion of said remotely located energy production facility with a ratepayer;
- generating an energy production report representative of the renewable energy produced at said remotely located energy production facility and associated with the ratepayer;
- sending the energy production report to a local metering device located locally with the ratepayer, wherein the local metering device is configured to receive the energy production report and wherein the local metering device is configured to measure the energy consumption of the ratepayer;
- receiving the energy production report sent from the remotely located energy production facility at the local metering device; and
- using the local metering device for processing the energy production report with the energy consumption of the ratepayer to determine a net energy consumption report.
31. The method of claim 29, wherein said sending comprises sending the energy production report wirelessly or over an existing power grid to the local metering device.
32. The method of claim 29, further comprising sending the net energy consumption report to a utility company.
33. The method of claim 32, wherein said sending the net energy consumption report to a utility company is done wirelessly or over an existing power grid
34. The method of claim 29, further comprising sending the net energy consumption report to a green credit accounting entity for assigning a green credit to said ratepayer.
35. The method of claim 29, further comprising sending the net energy consumption report to an accounting entity for calculating a green rebate for said ratepayer.
36. The method of claim 25, further comprising:
- measuring the electrical energy produced by one or more photovoltaic panels by at least one energy measuring device,
- collecting the measurement data from said at least one energy measuring devices by a control computer that is in communication with said at least one energy measuring device, and
- transmitting said measurement data and a fractional owner identification to a utility company by the control computer,
- wherein the utility company assigns a value to the energy produced by the photovoltaic panels and delivers the energy to end users.
37. The method of claim 36, wherein said end users are chosen in accordance with the fractional owners instructions.
38. The method of claim 25, further comprising:
- transmitting the electrical energy produced by the photovoltaic panels to at least on end user, and
- metering the electrical energy produced by the photovoltaic panels and delivered to said at least one end user by at least one green metering device, and
- transmitting the metered values and the end user identifier to the utility company.
Type: Application
Filed: Apr 16, 2009
Publication Date: Oct 21, 2010
Inventor: Steve Thorne (Berkeley, CA)
Application Number: 12/425,351