WO2008052224A2

WO2008052224A2 - Solar poly farm for solar power generation and agriculture

Info

Publication number: WO2008052224A2
Application number: PCT/US2007/082910
Authority: WO
Inventors: Arthur R. Zingher
Original assignee: Zingher Arthur R
Priority date: 2006-10-27
Filing date: 2007-10-29
Publication date: 2008-05-02
Also published as: WO2008052224A3

Abstract

The solar poly farm provides both a least two 'crops' (functions): irrigated agriculture and highly concentrated solar photovoltaic (HCS PV) power generation. Also this includes a water source and means for water flow which are shared by both crops. During the day, this water flow carries away heat to facilitate HCS PV power generation. During the night, this water flow provides irrigation for agriculture. The water flow subsystem includes a valve(s) to change between these two functions. There is a solar concentrator mirror and solar receiver, including photovoltaic (PV) cell(s). These are mounted on means to track the sun, atop support structures. These also provide support for climbing plants.

Description

Solar Poly Farm for Solar Power Generation and Agriculture

[0001] The solar poly farm provides both a least two "crops"

(functions): irrigated agriculture and highly concentrated solar photovoltaic (HCS PV) power generation. Also this includes a water source and means for water flow which are shared by both crops. During the day, this water flow carries away heat to facilitate HCS PV power generation. During the night, this water flow provides irrigation for agriculture. The water flow subsystem includes a valve(s) to change between these two functions. There is a solar concentrator mirror and solar receiver, including photovoltaic (PV) cell(s). These are mounted on means to track the sun, atop support structures. These also provide support for climbing plants.

[0002] Also this solar poly farm may provide additional useful

"crops": solar heat; solar thermal power; a crop that grows on the ground; fermentation of plant products; combustion of plan products; animals that eat plants. This solar poly farm provides synergism between plural crops. This synergism includes the amounts and types of resources, capital investment, and maintenance effort.

[0003] The topics of this teaching are solar power generation, preferably highly concentrated solar photo-voltaic (HCS PV) power generation, and agriculture, with irrigation. In the prior art, these topics were not considered closely related, and their synergism was not considered. For this invention, one goal is ecologically sustainable power generation. Another goal is to improve the total productivity versus total cost for this system.

Background

[0004] Eric Cummings, founder of Cool Earth Solar in Livermore,

CA, USA has publicly presented a system for HCS PV power generation. This was published on the internet at www.CoolEarthSolar.com. That taught power generation in a location and climate where the sun is clearly visible most days. A large balloon, with metallization on one hemisphere, provided a mirror to concentrate sunlight. On a solar tracker Actuator, this concentrator was mounted together with a solar receiver, including a highly efficient photovoltaic (PV) cell and water cooling. The mirror area was large compared to the PV cell area. Thus the sunlight is highly concentrated onto the PV cell(s). Normalized to the power generated, the area and cost of the PV cell(s) were very small, particularly compared to PV systems with nil concentration and a relatively large and costly flat PV panel. This described a farm for both solar power generation and agriculture.

[0005] USP 4,244,189 by Bliamptis taught energy generation by solar driven distillation and condensation of water, superimposed upon steep terrain with low and high elevations. This system included: a solar distillation pond at low elevation without any concentration; a vapor / air duct that climbed upward; a high elevation installation with a turbine driven by vapor / air, plus a condenser from vapor to liquid; a water reservoir at high elevation; a hydroelectric generating station along a descending pipe; a water reservoir at low elevation for water reuse for power generation, or for irrigation or drinking.

[0006] USP 4,087,971 by Hart taught a thermo-mechanical motor based on a shape memory alloy.

[0007] USP 4,259,629 by Korr et al taught a solar power array mounted upon a boat that floats upon an irrigation pond of a farm. This boat and array moved to track the sun.

[0008] USP 4,244,189 by Bliamptis: Please see above.

[0009] USP 4,980574 by Cirrito taught a D.C. to A.C. power supply for used with a solar PV system. This provided precisely controlled frequency and voltage suitable for off-the-shelf irrigation timers and controls.

[0010] USP 5,035,077 by Palmer taught a sealed chamber for horticultural growth in locations not normally conducive to efficient growing. [0011] USP 5,067,272 by Constanz taught an apparatus for water desalination and drip irrigation of row crops. This used sunlight, evaporation and condensation, without concentration of sunlight.

[0012] USP 5,101,593 by Bhatt taught a portable closed-chamber green house. This included apparatus to accumulate solar energy as electrical energy so as to drive irrigation pumps and fans, and to accumulate solar thermal energy to maintain desired temperatures.

[0013] USP 5,229,649 by Nielsen at al.

[0014] USP 5,500,506 by Hsu et al taught a system and method for conversion of organic waste into biogas, electrical power, compost, plus recycled water suitable for irrigation or discharge. This included an anaerobic digester and a green housed heated by sunlight.

[0015] USP 5,842,813 by Auvinen taught a cold-technology method for irrigation of cold arid areas.

[0016] USP 6,129,844 by Dobelmann taught a process for purification of waste water. This used waste water lightly loaded with organic waste for an anaerobic methane digestion followed by processing with sunlight. This produced recycled clean water, biogas and biomass.

[0017] USP 6,889,922 by Knight et al taught a moving apparatus for agricultural irrigation. A PV subsystem provided power to drive an electric motor, and thus to move this apparatus.

[0018] USP 7,168,207 by Andersen et al taught a system and method for drip irrigation of potato crops.

[0019] US Application 2003/0169006 by Allen taught an electrical driver circuit for use between a PV power source and a DC motor, particularly for solar powered irrigation or pumping.

[0020] US Application 2004/0200363 by Andersen et al is similar to

USP 7,168,207 by Andersen et al. [0021] US Application 2005/0205698 by Knight et al is similar to

USP 6,889,922 by Knight et al.

[0022] US Application 2006/0032938 by Pomey taught an irrigation system and a solar power assembly coupled to the irrigation system. Solar energy on a solar (PV) panel provided power to a battery for an irrigation controller.

[0023] US Application 2007/0012313 by Williams taught a system of recycled glass jars and metal cans. This can provide heat at a moderate temperature, can store this heat for later use, and can purify water by distillation.

Summary

[0024] In a preferred embodiment, this solar poly farm includes both irrigated agriculture and highly concentrated solar photovoltaic (HCS PV) power generation. Also this includes a water source and means for water flow which are shared by both these crops/ functions. During the day, this carries away heat to facilitate HCS PV power generation. During the night, this provides irrigation for agriculture. This farm is in a climate and location which is largely dry with direct bright sunlight. Direct local rainfall is rarely available, but nevertheless water is available from another source.

[0025] In a preferred embodiment, there are means to track the sun, balloon mirrors to concentrate sunlight, photo-voltaic cells to convert sunlight into electrical power, water cooling to remove heat, a valve(s) to change between the crops/functions. These are mounted on top of a support structure, such as stanchions and trellis. This support structure also provides support for climbing plants, such as grapes or tomatoes.

[0026] In various embodiments, this farm may grow several additional "crops" (functions), and there is more synergism between crops. Irrigation can facilitate growth of diverse crops, both climbing plants and ground plants. Various plant crops (or by-products) may be used to feed herbivores. Other plant crops (or by-products) may be used for fermentation. Still others may be dried and used for combustion. After the sunlight heats the water, it contains considerable heat at a moderately hot temperature. This can be useful for process heating, such as heating for fermentation, or for building heating. Also this can be augmented by combustion of other plant products. Another embodiment provides solar thermal power generation, using steam or water at very hot temperature. Nevertheless during the night, this farm can share resources with agriculture, particularly irrigation for agriculture. This invention provides synergism between the productions (growths) of these plural crops, including power, plants, and more. This synergism includes the amounts and types of resources for capital investments, maintenance, production and power distribution.

Brief Description of the Drawings

[0027] Several figures show the same preferred embodiment in several views.

[0028] Figure [Figl] shows the Trellis Group, Solar Groups, and irrigated agriculture in a large-scale isometric view.

[0029] Figure [Fig2] shows the Solar Group and nearby hardware as a medium scale cross section.

[0030] Figure [Fig3] shows the logical flow chart, including: sunlight; electrical power from photovoltaic and other sources; irrigation, agriculture and crops

[0031] Figure [Fig4] shows the water flow large scale schematic for two Trellis Rows.

[0032] Figure [Fig5] shows the water flow small scale schematic for a Solar Receiver.

[0033] Figure [Fig6] shows the Solar Receiver and nearby hardware in top and side finer scale views. [0034] Reference Numbers and Names

[0035] A Table provides every Reference Number and Name. These emphasize the logical structure. Each component or feature has the same reference number wherever it appears in the figures. These reference numbers are intended to clearly describe the logical structure of this invention. Therefore these correspond to a logical hierarchy or outline structure. Thus these resemble decimal factions rather than integers. For example the Solar Group [3] logically includes the Solar Receiver [32], and this logically includes PV Cell(s) [321]. These are analogous to decimal fractions: 0.3 is close to 0.32m and this is close to 0.321. These contrast with the integers 3, 32, 321, which less clearly express this logical hierarchy.

Table of Reference Numbers and Names

[1] Environmental Group [11] Sunlight

[111] Ambient Sunlight [112] Concentrated Sunlight [113] Concentrated Heat [12] Ground

[121] Ground very close to Trellis [122] Ground surrounding Trellis [123] Field [13] Wind [14] Dust [15] Gravity [2] Trellis Group

[21] Central Bundle Group [211] Water Tubes

[2111] Supply [2112] Return [212] Power Cables

[2121] Positive [2222] Negative

[213] Wires for Signals & Auxiliary Power [214] Strength Cable [22] Support Group

[221] Support Pole [2211] Top [2212] Middle [2213] Ground level [2214] Foot [222] Top Saddle [223] Support Mesh [224] Guy-wire [225] Anchor [23] Trellis Row Group [3] Solar Group

[31] Solar Concentrator [311] Balloon [312] Clear Area [313] Mirror Area [314] Bracket [315] Girdle [32] Solar Receiver

[321] PV Cell(s)

[322] Heat Transfer Means

[323] Valve(s)

[324] Nozzle

[325] Not used

[326] Circuit Board

[327] Flexible Region

[328] Connectors

[3281] Water

[32811] Supply [32811] Return [3282] Power Cables

[32821] Positive [32822] Negative [3283] Signals & Auxiliary Power [3284] Strength [33] Aiming Group

[331] Actuator between Solar Group and Central Bundle [332] Actuator between Central Bundle and Support Pole [333] Aiming controller [334] Aiming sensor [4] Irrigation Group

[41] Spray near Nozzle

[42] Spray near Ground very close to Trellis Group [43] Spray near Ground surrounding Trellis Group

[44] Spray near Solar Concentrator

[45] Irrigation Zone from one Spray

[46] Irrigation Zone from a Trellis Row

[47] Aggregate Irrigation Zone [5] Agriculture Group

[51] Climbing Plant

[52] Ground Plant

[53] Animal [6] Central Groups

[61] Central Water Group

[611] Water source

[612] Water destination

[613] Pump at supply water

[614] Pump for return water [62] Central Control Group

[621] Central Controller

[632] Communication Device

[623] Central Sensors

[7] Flow Schematic Group, Components not listed above [8] Other

Detailed Description

[0036] Unified description: Several figures show the same preferred embodiment in several views. Throughout these figures, the same reference number is used for the same component or feature. Therefore these figures will be described together.

[0037] Trellis: This is group [20]. This includes: Central Bundle [21],

Support Pole [221], Top Saddle [222] and Support Mesh [223].

[0038] Central Bundle Group: This is [21]. This includes: Water

Tubes [211], Power Cables [212], Wire for Signals and Auxiliary Power [213], and Strength Cables [214]. The strength cable is tightly stretched, so this can carry perpendicular loads.

[0039] Support Mesh: On the Support Pole [221], mounted on its

Middle [2212], there is a Support Mesh [223]. This provides mechanical support for Climbing Plants [51]. [0040] Solar Group: Along this Central Bundle at many locations, there is a Solar Group [30]. This includes a Solar Concentrator [31] a Solar Receiver [32] and an Aiming Group [33]. For reasons of graphic clarity, the Figure of the "Solar Group" may distort the geometry of components. This includes exaggerating the height of Central Bundle [21], and shrinking the height of the Flexible Region [327] and the Aiming Group [321].

[0041] Aiming Group: This is [33], and provides two-dimensional angular aiming of the Solar Group [30], including the Solar Concentrator [31] and the Solar Receiver [32]. During HCS PV power generation, these are accurately aligned with the Ambient Sunlight [H]. During spray mode (see below), the Aiming Group [33] aims the Spray [4]. This Aiming Group [33] includes an Actuator [331] that is located between a Solar Group [3] and the Central Bundle [21], which are described below. Also, there is corresponding flexibility between the Solar Group [3] and the Central Bundle [21].

[0042] The Central Bundle [21] rides in the Top Saddle [223] at the

Top [211] of the Support Pole [221], which are described below. The Top Saddle [222] includes an Actuator [332] to rotate the Central Bundle [21] and the attached Solar Groups [30]. This Actuator [332] is another part of the Aiming Group [33].

[0043] The two Actuators [331] and [332] are designed to work together to accurately and reliably aim the Solar Groups [3]. Their functions overlap for one rotary direction. This overlap can be used to improve reliability, and/ or for specialization, and/ or for simplification.

[0044] Solar Concentrator: This is [31], and includes: a Balloon [311] of clear tough thin film (such as polyimide), with a Clear Area [312] and a Mirror Area [313] with a very thin metal coating. This provides a mirror concentrator with notably small cost/ area. This can be replaced easily and economically, either when there is damage or during normal maintenance (such as following extreme wind, or every 5 years). [0045] Solar Receiver: This is [32], and includes: a PV cell(s) [321]; means to transfer heat [322]; a Valve(s) [323] to switch between the PV mode and the spray mode (see below); a Nozzle [324] to emit external Spray [4].

[0046] At one end, the Solar Receiver [32] provides tight connections with the Central Bundle [21]. At the other end, the Solar Receiver [32] provides tight connections with the PV Cell(s) [321]. Between these ends, there is a Flexible Region [327]. This can bend relatively easily, and thus accommodate the Tracking Actuator [331] and the variable geometry between the PV cells (s) [321] and the Central Bundle [21]. In a preferred embodiment, the Flexible Region [327] uses flexible materials and flexible structures, such as thin layers and/ or pleats.

[0047] HCS PV operation: To show the optics, a Solar Concentrator

[31] is shown in partial cut away. The Ambient Sunlight [111] illuminates each Solar Concentrator [31], and thus Concentrated Sunlight [112] illuminates each PV Cell(s) [311] of each Solar Receiver [32]. This generates electrical power, which conducts along the Power Cable [213] in the Central Bundle [21].

[0048] Heat transfer: Concentrated Sunlight [112] also generates

Concentrated Heat [113]. It is important to remove this heat, so the temperature of each PV cell(s) [321] stays moderate, so this operates properly. From each PV cell(s) [321], Concentrated Heat [113] conducts through Heat Transfer Means [322] into the flowing water.

[0049] Water flow for PV mode: In the Solar Receiver [32], the

Valve(s) [323] is switched so water flows as follows. Cool water feed in, from the Supply Tube [211], through the Water Supply Connector [361], to the Solar Receiver [32]. From the PV cell(s) [321], the Concentrated Heat [113] conducts through Heat Transfer Means [322] and into this water. The resulting warm water flows out, through the Solar Receiver [32], through the Return Water Connector [3262], into the Water Return Tube [212]. Thus all water flow is confined, and nil water is externally emitted. This mode is useful for HCS PV power generation.

[0050] Water flow for Spray mode: In the Solar Receiver [32], the

Valve(s) [323] is switched so water flows as follows. Water flows from the Water Supply Tube [3261], through the Water Supply Connector [3261], through the Solar Receiver [32], through a Valve(s) [323], and out through the Nozzle [324], and thus provides external Spray [4]. In this mode, almost all water is sprayed out, and the Water Return Tube [212] is not used directly. This mode is useful for self-rise and for irrigation, both described below.

[0051] Self-rinse operation: In the Solar Receiver [32], the water flow is switched to spray mode.

[0052] On this Solar Poly Farm at a central location, there is a Central Control Group [62] (Not Shown N.S.). This includes a Central Controller [64] (N.S) and Central Sensors [65] (N.S). These measure the direction and speed of the ambient Wind [13]. This data is feeds into the Central Controller [64] (N.S.). Through a Central Communicator [632] and the Signal Wire [215] of the Central Bundle [21] to each Solar Group [.0], the Central Controller [64] (N.S.) steers the Aiming Group [33]. Thus the Spray [4] is aimed against the effects of Wind [13] (N.S.) and Gravity [14]. Thus some Spray [44] returns onto the Solar Concentrator [312], particularly onto the Clear Area [312]. This rinses off any Dust [15] that otherwise would degrade HCS PV power generation. This self- rinse can be done without manual maintenance at each individual Solar Group [3]. This automation may enable less frequent manual maintenance.

[0053] Irrigation operation: At night or perhaps other times, the

HCS PV function is not active. Instead, significant parts of this system provide irrigation for agriculture.

[0054] On this Solar Poly Farm, there is a Central Water Group [61]

(Not Shown N.S.) that includes a Water Source [611] (N.S), Water Supply Destination [612] (N.S), and Water Pump [613] (N.S). These support both cooling for HCS PV power generation and support irrigation for agriculture. Also the Water Supply Tube [211] supports water flow both. However the Water Return Tube [212] is nearly unused during irrigation

[0055] During irrigation for agriculture, a Solar Receiver [32] operates in spray mode (see above) and thus provides external water Spray [4]. The Aiming Group [33] aims the Solar Receiver [32], including the Nozzle [324] and Spray [4]. For example, this can sweep the Spray [4] over the widest area, and/ or can aim the Spray [4] to compensate for Wind [13]. Thus water Spray [42] irrigates the Ground [121] very close to the Trellis Group [2]. Thus water Spray [43] also irrigates the Ground [122] surrounding the Trellis Group [2].

[0056] Plants: This water spray provides irrigation that facilitates growth of plants.

[0057] There are Climbing Plants [51] such as grapes and tomatoes.

Their roots grow in the Ground [121] very close to the Trellis Group [2]. From here, these plants grow up and onto to the Support Mesh [223]. The preferred embodiment includes Climbing Plants [51] growing along and upon both sides of this Support Mesh [223] Trellis. Nevertheless for graphical clarity, these Figures show Climbing Plants [51] on only one side. On the Ground [122] surrounding the Trellis Group [2], there are Ground Plants [52]. In a climate and location that are bright and dry, this invention provides very favorable growing conditions for plants.

[0058] First, there is controllable irrigation for agriculture. Second, irrigation can carry useful additives, such as fertilizer, agents to control pests, agents to control plant growth. Third, this system blocks only a moderate fraction of the Ambient Sunlight [111]. Thus most is still available for agriculture. Fourth, for the Climbing Plants [51] during midday, the very local Ambient Sunlight [111] and very local temperature are slightly shielded. For some types of Climbing Plant [51], this moderation may be helpful. [0059] Animals: Some plants products (or by-products) are gathered from these Plants [51] and/ or [52], and subsequently fed to animals at other locations. Also, at some seasons, an Animal [53] is directly on this Ground [122] and feed upon these Plants [51] and/ or [52] and/or their by-products. This may be an individual animal, or a herd (flock) of animals.

[0060] Support Pole and Guy-Wire: Because of wind and gravity, sometimes there will be strong forces on the Trellis Group [2] and attached Solar Groups [3]. This requires considerable strength in the Support Poles [221]. The preferred embodiment is a strong hollow metal tube or beam [221]. Also this includes an Anchor [225], and a long Foot [2214]. These are deeply implanted into the Ground [224] very close to the Trellis Group [2]. The Support Pole [221] is optionally reinforced with diagonal Guy- wires [224] to Anchors [225].

[0061] Water spreading: From each Solar Group [3], irrigation water will spread by direct spray, possibly followed by other water spreading mechanisms. These include permeation of soil, stratum, other geological structures; flow down inclined ground, rivulet, hill, stream, stratum, crack, fracture, etc.; air-borne droplets, vapor, humidity, etc; and more.

[0062] Irrigation Zone and Trellis Row: These various spreading processes act together, and thus define an Irrigation Zone [45] that corresponds to this Solar Group [3]. Likewise, each Trellis Group [2] and its Solar Groups [3] together define a corresponding Irrigation Zone [46].

[0063] A Trellis Row [23] includes a Trellis Group [2], its Solar

Groups [3], includes Ground [121] very close to the Trellis, and includes Ground [122] surrounding the Trellis. In the preferred embodiment, each Trellis Row [23] is designed so all its Ground [121, 122] is irrigated.

[0064] Large Field: For example, consider a Field [123] which is too large to irrigate completely by any individual Trellis Row [23], and much too large to irrigate by any individual Solar Group [3]. [0065] In a preferred embodiment, this large Field [123] is covered by Trellis Rows [23]. Adjacent Trellis Rows [23] are approximately parallel, separated by enough space for farm machines to travel between them. Thus an array of Trellis Rows [23] substantially covers the entire large Field [123]. Preferably every Solar Group [3] can be productive for both solar power generation and for irrigated agriculture. In the preferred embodiment, the Trellis Rows [23] finely interspersed to irrigated prevent substantial areas without irrigation.

[0066] Thus the Trellis Rows [23] adequately irrigate almost all this

Field [123], and prevent areas of over-irrigation or under-irrigation. In the preferred embodiment, the design of the array of Trellis Rows [23] also optimizes various goals for electrical power and economics.

[0067] Supply Water Source and Return Water Destination

[0068] In the preferred embodiment, some of its heat is harvested for a useful purpose. Partially efficient harvesting is feasible, even though thermodynamics puts a significant constraint.

[0069] A first embodiment is processing food, including plant products grown on-site. This results in relatively cool water to reuse as supply water.

[0070] A second embodiment uses the return water for preheating for thermal power generation. For example, the hot return water transfers heat to a "working fluid" (typically a gas). This is further heated by combustion. Next the working fluid drives a stream turbine, and hence drives an electro-magnetic generator. After the preheating, the resulting water is less hot.

[0071] After use for food processing or thermal power generation, the resulting return water goes through a "cooling tower", similar to those used for air-conditioning in large buildings. This finally provides cool water for re-use as supply water. Another embodiment uses one reservoir as both water supply source and return water destination. This offers relatively low capital cost. However this does not harvest the heat, and water is lost by evaporation.

[0072] Logical Flow Chart [Fig3]

[0073] Shared hardware and operation: There is significant overlap between the means for power generation and the means for irrigation of agriculture. These share significant hardware and operations. Supply Water flows from a Supply Water Source , through a Supply Pump, into and along each Supply Tube. Eventually Supply Water flows through each Solar Receiver and Valve(s).

[0074] During power generation: The Ambient Sunlight shines on each Solar Group, including its Solar Concentrator. This projects Concentrated Sunlight onto the PV Cell(s). This generates power that feeds into the Power Cables. Also this generates Concentrated Heat that goes through Heat Transfer Means.

[0075] During power generation, the Valve(s) steers the Supply

Water through the Heat Transfer Means. Here Concentrated Heat is transferred to Supply Water. Thus it becomes Return Water that flows into and along the Return Tube. Eventually this flows to the Return Pump and Return Water Destination.

[0076] During irrigation: In each Solar Group and its Solar

Receiver, the Supply Water is steered by the Valve(s) to the Nozzle, and thus provides external Spray. Some Spray reaches the Ground very close to the Trellis and thus spreads to a Climbing Plant (s). Some Spray reaches the Ground surrounding the Trellis and spreads to a Ground Plant(s). For each plant, this Irrigation Group and Ambient Sunlight are pivotal resources to enable plant growth, fruitfulness and agricultural productivity.

[0077] Large Scale Water Flow Schematic [Fig4] [0078] For the preferred embodiment, this Figure is a schematic for water flow in two adjacent Trellis Rows.

[0079] Schematic: Each Trellis and Central Bundle has two parallel

Tubes, for Supply Water and Return Water. Each Solar Receiver is connected across both Tubes. Thus water flow is topologically parallel through plural Solar Receivers. Thus every Solar Receiver gets Supply Water that is relatively cool.

[0080] This schematic shows two adjacent rows, with anti-parallel flow directions, and U-shaped tubes connecting these two rows. Thus the Water Supply Source and the Water Return Destination are close together. This facilitates central water facilities, particularly to take advantage of the heated return water. Also, this removes heat and thus provides cool water as supply water for reuse.

[0081] Hydraulic features: This preferred embodiment has several features reduce viscous friction and turbulent friction, and thus to reduce the power to pump water. The Supply Tube and Return Tube each have comparatively large flow area. This reduces the linear flow speed, compared to the volumetric flow rate. Also, each Tube includes a T-junction for each Solar Receiver. This T-junction is internally well streamlined, particularly for flow straight along the tube.

[0082] This preferred embodiment has several features to facilitate balancing flow between Solar Receivers. Every streamline flows exactly once through a Solar Receiver. This schematic balances most pressure gradients along these Tubes. If it is feasible to taper these Tubes in opposite directions, then this balancing can be quite accurate.

[0083] If the flow path is extremely long, then it may include an additional Water Pump(s). Counter-example: By contrast, a less preferred embodiment (not shown) uses has a unified (single) flow of water in a unified (single) tube. Thus an upstream Solar Receiver adds heat that preheats and degrades the water flowing into a downstream Solar Receiver. Thus its PV cell(s) will operate relatively hot.

[0084] Fine Scale Water Flow Schematic [Fig5]

[0085] For the preferred embodiment, this Figure is a schematic for water flow inside a Solar Receiver. During all Modes: From the Supply Tube, some Supply Water enters through the Supply Water Connector and into the Solar Receiver. An Actuator activates a Valve that steers water flow between thee modes: Power generation; Zero flow; Spray.

[0086] During Power Generation Mode: This Valve steers Supply

Water to flow through Heat Transfer Means and thus to receive Concentrated Heat. In a preferred embodiment, the water through narrow passages between thermal surfaces (fins) with relatively large area. In another embodiment, the water flows through an array of many nozzles, and impinges on a heat transfer surface. This provides Return Water that flows through a Return Water Connector and into the Return Tube .

[0087] During Off Mode: The Valve blocks Supply Water and

Return Water flow through the Solar Receiver.During Spray Mode: The Supply Water goes through the Valve and is steered to the Nozzle and thus provides external Spray.

[0088] Easy maintenance: The preferred embodiment facilitates changing a Solar Receiver, without spilling water, and without draining the Water Tubes. Each Water Connector have an implicit valve-like feature. This prevents spilling water when the Connector is opened, or being connected, or being disconnected. For example, a well-know trade-name for this is a "Quick Connector".

[0089] Other options: These options are NOT preferred, but might be useful in some cases. [0090] {} A pin-wheel rotary sprinkler in place of the Nozzle. This uses some water pressure to provide wider spray.

[0091] {} A small auxiliary pump upstream of the Nozzle. This provides additional pressure for the Spray.

[0092] {} Means to adjust water flow rate through the Means for heat transfer

[0093] {} Means to adjust the Nozzle. This adjusts the shape of the

Spray.

[0094] {} An explicit check-valve. This more rigorously prevent backwards flow of water during transitions or abnormal conditions.

[0095] {} Water connectors without the implicit valve-like feature.

This requires interrupting PV operation or Spray operation, and draining the Water Tubes in order to change a Solar Receiver without spilling water. This may incur considerable time, effort and disruption.

[0096] {} Means for a more direct rinse for the Solar Collector. This provides an additional Nozzle and provides an additional Mode for Valves and Actuator.

[0097] Central Bundle, Further Description

[0098] In the Central Bundle , each Water Tube is surrounded by thermal insulation. This prevents a "thermal short circuit" between these Tubes, and prevents heat transfer to/ from Ambient Sunlight or Wind .

[0099] The Central Bundle also includes conduits (cables and wires or fibers) for mechanical strength, electrical power, electronic signals and auxiliary electrical power. For clarity in showing the Central Bundle, these all are shown as being distinct and separated. Nevertheless these may be unified in various degrees. The preferred embodiment depends on details of cost, manufacturing, installation, maintenance, reliability, and engineering functions (mechanical, thermal, power or communication). [00100] Solar Receiver, Further Description [Fig6]

[00101] Flexible Printed Circuit: In the preferred embodiment, the

Solar Receiver preferably includes a flexible printer circuit with at a layer for fluid flow and a layer for electrical flow. This carries other components, such PV Cell(s), Valve(s), Actuator(s), Heat Transfer Means, Sensor(s), Connectors, Means for communication and protocol. Analogous to a classical printed circuit board, this embodiment has potential for economical volume products and reliable operation.

[00102] The Solar Receiver preferably includes a "flexible printed circuit for electricity". This conducts: primary electrical power (generated from sunlight); auxiliary power (to activate actuator, sensors, etc); signals.

[00103] The Solar Receiver preferably includes a "flexible printed circuit for water flow", such as molded soft plastic and/ or plated metal bellows. This provides water channels. For example, Figure is a fine-scale cross section that water supply channels. Water return channels are in a different plane, so are not visible here.

[00104] The Solar Receiver preferably carries the Valve(s), Actuator,

Means for heat transfer.

[00105] The Solar Receiver preferably carries a Sensor(s). This may measure one or more of the following: temperature; water flow and pressure; power current and voltage; aiming parameters; mode signals; error signals; self- diagnostic signals.

[00106] The Solar Receiver preferably carries Means for communication and protocol. Preferably this provides: Communication to and from Actuator (s) and Sensor (s); Communication protocols to identify and/ or select a particular component in a particular Solar Receiver.

[00107] Flexible Region: The Solar Receiver preferably includes a

Flexible Region. Thus geometric variability (necessary for aiming) is compatible with sustained connectivity (necessary for flow of water, power, signals, etc). Other embodiments provide flexibility at various locations, such as in the Central Bundle and/ or on either side of the Connectors and/ or in the Solar Receiver.

[00108] Variations, Feedback and Automation

[00109] On this Solar Poly Farm between various locations and times, there are typically variations in the need for water flow for power generation and for irrigation of agriculture. Causes of variations often include:

[00110] {} Current weather including sun elevation, clouds or other shade, temperature, wind, humidity, rain, fog, dew; Consequences of prior weather

[00111] {} Power demand for immediate delivery and for storage;

[00112] {} Topography and geology, particularly soil conditions;

[00113] {} Plant types, growth requirements, results of prior conditions;

[00114] {} Hardware tolerances; Operating tolerances;

[00115] {} Leaking; Clogging; Other abnormalities or failures.

[00116] Therefore this system provides water flow in each Solar

Receiver to match the local requirements.

[00117] To observe these variations, there are sensors that feed data into Computer with relevant software. This provides signals to control this system. Controllable water-related components include: Water Pumps; Aiming Groups; Solar Receivers. The latter includes Valve(s), optionally includes the Means (N.S.) to adjust the Nozzle, and optionally includes the Means (N.S.) to adjust water flow through the Heat Transfer Means.

[00118] In the preferred embodiment, the water flow is modulated by turning on and off these components. This modulation avoids or minimizes the need for analog or proportional control hardware. Nevertheless, this modulation may be adequate for many instances of this invention.

[00119] In addition, the sensors, computer and communication subsystems also provide: Sensing and display of system status; Control for power generation and irrigation; Aiming to track sunlight for power generation; Aiming the Spray for irrigation; Self-rinsing. This automation reduces the need for human intervention, particularly during normal operation.

[00120] Significance

[00121] This invention teaches the following concepts, and these are fulfilled by the preferred embodiment.

[00122] This invention provides means for water flow.

[00123] In the preferred embodiment, these means include the water source and water destination, the water tubes, the water connectors, parts of the solar receiver including the valve(s), plus corresponding water return elements, plus more.

[00124] This invention provides means for water flow to transfer heat from photovoltaic means to generate power from highly concentrated sunlight.

[00125] In the preferred embodiment during PV operation, ambient sunlight falls upon the solar concentrator and hence provides highly concentrated sunlight. This is absorbed by a photovoltaic cell(s) and thus generates power. Also this deposits heat into the photovoltaic cell(s). This heat is removed through the heat transfer means to the flowing water. This flowing water is supplied by means including the water source, supply pump, supply tube, water supply connector, valve(s), plus other parts of the Solar Receiver. For further use in power generation, the flowing water is cycled back by means of other parts of the Solar Receiver, valve(s), water return connector, water return tube, water return pump, water return destination and more.

[00126] This invention provides means for water flow to transfer heat from photovoltaic means to generate power from highly concentrated sunlight. [00127] In the preferred embodiment during spray operation, the water flow, valve(s), nozzle together provide an external spray of water. The aiming mechanism directs this water to fall upon the ground closely under the trellis, and/ or upon the ground surrounding the trellis. This irrigates the climbing plant(s) and/ or irrigates the ground plant(s).

[00128] These two means share significant hardware, as compared to separately providing equivalent irrigated agriculture and/ or equivalent solar power generation.

[00129] In the preferred embodiment, the shared hardware includes the water source, water supply pump, water supply tube, water supply connector, parts of the solar receiver, plus the trellis group. This shared hardware is significant compared to a separate system for equivalent spray irrigation.

[00130] The means for solar power generation and the means for irrigated agriculture are co-located. As described above, the preferred embodiment teaches water spreading, and provides an irrigation zone corresponding to each solar group, and to each trellis row. Also, a large field is covered with trellis rows, and these irrigate this field.

[00131] These two means are interspersed substantially, thoroughly and finely. As described above, in the preferred embodiment the area for solar power generation is substantially, thoroughly and finely interspersed with the area for irrigated agriculture.

[00132] In the preferred embodiment, the supply line is more regional and major, and in comparison the irrigation line is more local and minor. A farm field generally has fewer supply lines compared to more irrigation lines. Each supply line generally is longer, has larger cross-section, and provides larger flow. By comparison, each irrigation line generally is shorter, has smaller cross-section, and provides smaller flow. The cost per length generally is more for a supply line and less for an irrigation line. [00133] This invention favorably contrasts with a separate equivalent system for power generation system, plus a separate equivalent system for irrigation of agriculture. This invention shares the same field for both functions. This sharing saves real estate investment. This invention shares most hardware for the regional and major water flow. This invention shares and saves maintenance. This invention shares the water supply source, its access facilities (such as an aqueduct), and some contractual arrangements. However, to include irrigation generally consumes more water than does power generation alone

[00134] This invention enables both functions to achieve almost full productivity, compared to the separated alternative. Thus the solar power system effectively provides a large bonus: most regional and major parts of a system for agricultural irrigation. Thus this invention achieves synergism and savings that are quite significant compared to the resources for agricultural irrigation.

[00135] To better understand this invention, the following concepts are useful. In the preferred embodiment, the water-supply line includes everything from the Water Supply Source to the Valve. The water return line includes everything from here, through the Heat Transfer Means to the Water Return Destination. The irrigation line includes everything along the path for water from Valve through the Nozzle to the Plant (s). Thus the Irrigation line includes the nozzle, spray, diffusion or flow on, in, through or under the ground, to the Plant. These three lines have analogous meaning for other embodiments.

[00136] Sunlight Concentration is defined as the ratio of power/ area, compared to ambient sunlight. The preferred embodiment is designed for 500X. Suppose IX to 1OX is defined as mild concentration; 10x to IOOX is defined as medium concentration; IOOX or more is defined as high concentration.

[00137] Generalizations [00138] The concepts of this invention have been illustrated by the preferred embodiment. However these concepts can be generalized as follows.

[00139] This invention has been described for photovoltaic power generation. More generally, this invention applies to diverse applications for solar concentration and flowing water. This provides such an application to be synergistically combined with irrigation for agriculture.

[00140] This invention applies to solar power generation using various processes: photovoltaic power generation; thermo-electric power generation; thermo-mechanical power generation (e.g.: a steam engine or a Stirling engine); photo-chemical power generation (e.g.; chemical reactions induced by sunlight); and more.

[00141] This can be generalized to a system to produce hot water from concentrated sunlight (e.g.: for domestic use or for an industrial process). This can be generalized to a system to purify water by concentrated sunlight, particularly when combined with growth of non-food plants.

[00142] This invention has been described for irrigation to grow plants for food and related purposes. This can be generalized to irrigation to grow plants for fibers, fuel, decoration or other non-food use. An example is irrigation to cultivate grass on a golf course.

[00143] This invention has been described for irrigation through a nozzle and spray. This can be generalized to spray irrigation with additional means to project the water spray. One example uses centrifugal spinners with nozzles. This invention can be applied to irrigation through small side tube or side-channel, which spread out from a trellis and solar group. In this case, irrigation includes a hierarchy, from upstream components which are few and coarse, to downstream components which are many and fine. The solar power system and irrigation system share the water source, water supply pump, water supply tube, valve(s) etc. When these are not used for solar power generation, these provide water flow into smaller side tubes. These provide water precisely at the roots of the plant, and thus minimize wasted water.

[00144] This invention has been described using pure water.

However, this can be generalized to: water with desirable additives (such as fertilizer); with unavoidable impurities (such as dissolved chemicals, or small particles); with adverse impurities (such as "gray water" produced from tertiary sewage treatment). This invention has been described using a water connector between the central bundle and the solar receiver. Instead, a thermal interface can be provided between the central bundle and the solar receiver. This greatly reduces the need to open the water flow.

[00145] This invention has been described using a trellis row, and a solar concentrator that is hemispheric and moderate-sized. This can be generalized to other structures for concentrated solar power: a linear trough concentrator; a field of parabolic concentrators; a field with one or more "power towers", each surrounded by an array of "heliostats"; concentration of sunlight by a ratio that is moderate or medium or large (such as 5X, 5OX, 500X); solar concentrators and solar receivers that are relatively small, medium, large or giant (such as 50, 500, 5k, 50k Watts during standard ambient sunlight).

[00146] This invention has been described using two tubes for separate water supply and water return. This invention can be generalized to using a single tube and a single water flow. This invention has been described with emphasis on sharing of the water subsystem between solar power generation and agriculture, and the resulting synergism. In addition this invention can be generalized to sharing of other resources and resulting synergism. For example, the mechanical structure of the trellis group is another shared asset. This provides additional synergism between solar power and agriculture.

[00147] In most cases, the largest mechanical load is due the Central

Bundle and/ or the Solar Concentrator. In various embodiments, the other components may be support through these, or may be supported directly. In various embodiments, the Support Poles and Strength Cables ultimately support all elevated components.

[00148] In the preferred embodiment, the heat is harvested for some useful purpose (e.g.: processing food from plants). This results in relatively cool water to reuse as supply water. The next embodiment would be a "cooling tower", similar to those used for air-conditioning in large buildings. A distant third choice would be to use the same reservoir. In the relevant climate, this would waste water by evaporation loss.

[00149] In the preferred embodiment, the Supply and Return Tubes are part of the Central Bundle that stretches between Support Poles. Each Solar Group has a short Flexible section to connect to this Supply Tube. In the preferred embodiment, the Supply and Return Tube run in the Central Bundle and thus are elevated. In a different embodiment, the Supply and Return Tubes run along the Ground. Each Solar Group includes flexible hoses log enough to connect to these Tubes on the Ground. This embodiment avoids support the weight of the Supply and Return Tubes and the water they contain. However this embodiment requires adding the flexible hoses.

[00150] The system has an optical train that concentrates ambient sunlight onto the PV cell(s). In the preferred embodiment, the Solar Concentrator Balloon includes a Metallized Area that reflects and concentrates ambient sunlight. Also this Balloon includes a Clear Area that transmits ambient sunlight and concentrated sunlight, and also physically protects the reflective surface of the metallized area. Thus the optical train includes three optical components: the Clear area; the Metallized area; the PV cell(s). More generally, other embodiments may have more or fewer optical components in the optical train.

[00151] The preferred embodiment uses balloon mirrors. These are adequate optically, have excellent cost/ area, and adequately durable given occasional replacement. Other embodiments use various optical trains and various optical components. These may include an optical component(s) that operates by: reflection; refraction; transparency; diffraction effects; interference effects; plasmonic effects (Surface plasmons are solid-state physics effects that can interact with light.)

[00152] Also the optical train may include an optical component that is:

[00153] {} Solid, such as a solid lens of glass

[00154] {} Fresnel-structure, such a Fresnel bull-eye lens

[00155] {} Planar, such as medium thickness mirror

[00156] {} A thin layer. One example is mirror including a thin metal layer on a thin plastic film.

[00157] The optical train can concentrates in two dimensions. The preferred embodiment is parabolic hemisphere mirror. Another embodiment is disk-like lens. The optical train can concentrate in one dimension. Two embodiments are a cylindrical optical mirror and a cylindrical lens.

[00158] In the preferred embodiment, the valve includes a separate electro-magnetic electro-mechanical actuator plus a separated hydraulic valve. Other embodiments include various valves types: separate electro-mechanical actuator and mechanical valve; voltage control of piezoelectric actuator that controls control mechanical valve; actuator distinct from or integrated with hydraulic valve; valve controlled by gravity and orientation, and hence by aiming mechanism; valve controlled by temperature; nozzle with integrated valve; nozzle-cap as a manual valve; manually controlled mechanical valve."

[00159] This system may include one of the above, or a row of the above, or an array of the above, or a field of the above. It addition to these explicit generalizations, someone with normal skills in relevant arts can use this invention to practice additional embodiments. [00160] Synergism [00161] This invention provides solar power generation and irrigated agriculture significantly more efficiently than if these two functions were provided separately. Therefore this invention achieves significant synergism between these two functions. This invention provides many features, assets, investments that contribute with such synergism to both solar power generation and to irrigated agriculture. This synergism applies to initial capital investments, to hardware itself, to installation, to maintenance.

[00162] These include real estate resources, including land and climate (see below) and access (access roads, access to water source, and access to the electrical grid). These include the water source, water supply pump, water supply tube, water connectors, valve(s), other parts of the Solar Receiver, and more. These include support poles and other parts of the trellis group that provide mechanical support for solar power generation, for irrigation, for climbing plant. These include on-site solar power generation and on-site consumption of power to pump water to irrigate agriculture.

[00163] These include on-site generation of hot water and optional use of heat for on-site processing or use of agricultural products. One optional embodiment is on-site-cooking of fruits from plants grown on-site. A second optional embodiment is on-site fermentation and purification of bio-fuel from plants grown on-site. A third optional embodiment is to use hot water from on- site solar power generation for preheating ahead of on-site combustion of plants grown on-site. The resulting heat can be used for on-site processing of agricultural products, or to activate on-site thermo-mechanical power generation. These include use of the water spray for irrigated agriculture and for self-rinsing for solar power generation.

[00164] There is considerable overlap between site conditions that facilitate solar power generation and those that facilitate irrigated agriculture. This overlap facilitates synergism between these two functions. Solar power generation and irrigated agriculture are each facilitated by: abundance of bright ambient sunlight; climate with absence or shortage of on-site clouds, rain, snow, heavy fog, heavy mist, heavy dew, severe storms, intense winds; topography that is flat or moderately sloped, without steep inclination; absence or rarity of topographic shadows that block sunlight; sufficient access to a sufficient water source with sufficiently low coast; low land prices.

[00165] Concentrated solar power generation differs in requiring clear direct ambient sunlight, with none or little optical scattering. Irrigated agriculture differs in requiring favorable soil and related chemistry.

Claims

CLAIMSWhat is claimed is:

1. A system for agricultural irrigation and power generation, comprising: a power generator arranged to receive concentrated sunlight; a supply-water line providing flowing water for removing heat from the power generator; and a valve arranged to selectively connect the supply water line to an irrigation line.

2. The system for agricultural irrigation and power generation according to claim 1, wherein the power generator is a photovoltaic cell driven by highly concentrated sunlight.

3. The system for agricultural irrigation and power generation according to claim 1, wherein the irrigation line is a local irrigation line.

4. The system for agricultural irrigation and power generation according to claim 3, wherein the local irrigation line is arranged to irrigate a plant near the power generation system.

5. The system for agricultural irrigation and power generation according to claim 3, wherein the local irrigation line has a cross-section substantially smaller than the supply-line, and the local irrigation line terminates near the power generation system.

6. The system for agricultural irrigation and power generation according to claim 1, wherein the power generator is a photo-voltaic power generator, a thermo-electric power generator, a thermo-mechanical power generator, a photochemical power generator, or a bio-photo-voltaic power generator.

7. The system for agricultural irrigation and power generation according to claim 1, wherein the power generator cooperates with an optical train that is arranged to concentrate sunlight on the power generator.

8. The system for agricultural irrigation and power generation according to claim 7, wherein the optical train includes a mirror, a lens, a balloon mirror, a Fresnel-style lens, a diffractive element, or a plasmonic optical device.

9. The system for agricultural irrigation and power generation according to claim 7, wherein the irrigation line comprises a spray nozzle for rinsing at least part of the optical train.

10. The system for agricultural irrigation and power generation according to claim 1, further including a drain-line for removing the heated flowing water from the power generator and wherein the heated flowing water is cooled and reused as supply water.

11. The system for agricultural irrigation and power generation according to claim 1, wherein the supply-water line, the irrigation line, and the power generator use the same mechanical support.

12. The system for agricultural irrigation and power generation according to claim 1, wherein the supply-water line is bundled with another support line to suspend and mechanically support the power generation module.

13. The system for agricultural irrigation and power generation according to claim 1, wherein the irrigation line is used to irrigate a plant and comprises a spray nozzle, drip line, soaker hose, or a diverter hose leading to a side channel.

14. The system for agricultural irrigation and power generation according to claim 1, wherein the valve has a first mode that routes water from the supply- water line to the power generator, and a second mode that routes water from the supply -water line to the irrigation line.

15. A system for agricultural irrigation and power generation, comprising: a support structure; a power generator; an optical train connected to the support structure and arranged to direct concentrated sunlight to the power generator; a supply -water line for providing flowing water for removing heat from the power generator; an irrigation line; and wherein the supply- water line operates in a first mode to provide flowing water to the power generator, and operates in a second mode to provide flowing water to the irrigation line.

16. The system for agricultural irrigation and power generation according to claim 15, wherein the power generator, supply-line, and irrigation line are each connected to the support structure.

17. The system for agricultural irrigation and power generation according to claim 15, wherein the power generator is a photo-voltaic power generator, a thermo-electric power generator, a thermo-mechanical power generator, a photochemical power generator, or a bio-photo-voltaic power generator.

18. The system for agricultural irrigation and power generation according to claim 15, further comprising a valve and a controller, wherein the controller selectively places the supply-line into its first mode or into its second mode.

19. The system for agricultural irrigation and power generation according to claim 15, further including a drain-line for removing the heated flowing water from the power generator to a remote location.

20. A system for agricultural irrigation and power generation, comprising: a power generator arranged to receive concentrated sunlight; a supply-water line providing flowing water for removing heat from the power generator; an irrigation line; and wherein the supply- water line operates in a first mode to provide flowing water to the power generator, and operates in a second mode to provide flowing water to the irrigation line.