Osmosis energy storage & restoration system and indirect solar powerplant

Abstract

Natural water evaporation is a buffered process with huge energy absorption from solar & its derivative wind energy. When large surface shallow pool filled with aqueous solution is exposed under sky, the most portion of natural energy will be spent for pulling water out of water molecules cluster, yet there is still some energy for splitting water from solutes, then the concentration increases, in turn, despite the main former energy is sacrificed, but the stronger solution can redeem most the latter energy during a process of Pressure Retarded Osmosis (PRO), via membranes separating solution & available water in situ, then the redeemed energy serves as utilizable power output, with the assistance of key units or components: the osmotic to hydraulic pressure transformer, the hydraulic oil current rectification fluidic circuit & a hydraulic motor. With minor adaptation, same mechanism can also be embodied as: mobile osmosis engine, osmosis vehicle battery, yard synergy-osmosis power system, Grid electricity and miscellaneous renewable energy to osmosis energy storage, even desert to oasis remediation with seawater intake solar-via-osmosis powerplant & parasitic freshwater factory.

Claims

1. A method of osmosis energy restoration that comprises three linked energy conversion steps or processes: forward osmosis DC to hydraulic oil AC, oil AC to oil DC, oil DC to shaft AC, and the optional shaft AC to electrons AC or DC can be attached to previous main link as last conversion. Execution of this method will output energy, and it will result in gradual dilution of the working solution until inacceptable preset threshold reaches.

2. A derivative method from osmosis energy storage that is equal to the reverse processes of claim 1 method. Execution of this method needs energy input, and it will result in gradual concentration of the working solution until saturation status reaches.

3. The apparatus that is implemented with the claim 1 method combining optionally the reverse of claim 1 method, and that can usually be embodied in a system with any one selection or the preferred combination from following application spectra: solar-via-osmosis power generation, mobile osmosis engine, osmosis starter battery for vehicles, yard synergy-osmosis power system, commercial hydro energy and renewable energy to osmosis energy storage, desert to oasis long time remediation with seawater intake solar-via-osmosis powerplant and parasitic freshwater factory, and so on.

4. In addition to the claim 3, if the optional reverse processes of claim 1 method is not used or only used speculatively or occasionally for concentrating the working solution by reverse osmosis with the outsourced renewable intermittent energy or with non-peak low priced hydro-grid energy as an advantage-taking strategy, then a solar evaporation panel or pool or lake or whatever equivalence must exist, and its surface is intentionally designed as large as possible and feasible so as to maximally absorb the solar energy or ambient heat for evaporation that renders equivalent effect with the reverse osmosis method. Any additional practice with good common sense can be applied above evaporation surface to prevent solution from dilution caused by non-ideal weather.

5. In addition to all claims, hydraulic oil and aqueous solution are isolated in separate cylinder compartments, and an electric module governs data acquisition, valves/switches control, etc.

Description

DETAIL DESCRIPTION ON ALL DRAWINGS, POSSIBLE EMBODIMENTS & RELEVANT ANALYSIS

Description on FIG. 1

[0157] FIG. 1 shows the closeup view of interface between aqueous solution and hydraulic oil.

[0158] It is purposed to only emphasize on the mutual isolation between hydraulic oil and osmosis solution, not restrict how to realize isolation or how far between their holding compartments.

[0159] As to embodiment forms, there are many possible, this figure just illustrates one form.

[0160] In this figure, the semi-permeable membrane is drawn in a doted-Z shape; aqueous solution and oil are both drawn in wavy area, and respectively indicated by callout labels; anchoring points are drawn in shaded triangle symbol; all unmentioned elements are marked by callout labels, and some important elements will be described in more detail hereafter if necessary.

[0161] Although the hydraulic cylinder & osmosis cylinder are drawn as different components & coupled by pins, however it may be only good for DlYers but manufacturers may prefer to fabricate them as a whole unit for massive production.

[0162] The piston diameter of osmosis cylinder is marked as ?.sub.1, hydraulic piston as ?.sub.2, shaft diameter as ?.sub.3, and the osmotic pressure is P.sub.1, oil pressure P.sub.2. There is equation for above 5 parameters:

P.sub.1*??.sub.1.sup.2/4=P.sub.2*?(?.sub.2.sup.2??.sub.3.sup.2)/4 or P.sub.2=P.sub.1*?.sub.1.sup.2/(?.sub.2.sup.2??.sub.3.sup.2)

[0163] Obviously if ?.sub.1>?.sub.2 then oil pressure will be greater than osmotic pressure, vice versa, that is why sometimes it is also named as pressure transformer. Therefore it is possible to pre-design working states for solution & oil sides to enable both run in respective isolated space with best performance without the bothersome blend of water and oil.

[0164] For example, if the saturated salt solution is used, then the osmotic pressure is commensurate with the rated pressure for commercial hydraulic products, hence ?.sub.1?(?.sub.2.sup.2??.sub.3.sup.2).sup.0.5 is usually OK, but if seawater is used, then ?.sub.1?4.5(?.sub.2.sup.2??.sub.3.sup.2)).sup.0.5 shall be the correct quantity correlation of the piston's diameters, so as to still enjoy popular hydraulic parts.

[0165] During the process of freshwater osmosis through the membrane, the pushed oil side will send powerful oil current to the connected hydraulic hose, so as to do work in loads; meanwhile, oil in the opposite side of hydraulic piston will appear vacuum state, so as to suck inward the return oil from loads exhaust port or oil tank with air breather.

[0166] Despite that minor leakage may occur around rim of osmosis piston because of not ideal viscosity of solution & potential corrosion, anyway, it is still tolerable and worthy even periodic change of some cheap parts may be inevitable, just based on good expectation of its efficient conversion from osmotic power to hydraulic power.

[0167] More similar embodiments are presented in next two figures.

Description on FIG. 2

[0168] FIG. 2 shows another variety of the pressure transformer with the compactor interface of water & hydraulic oil.

[0169] There is a dummy end in either oil cylinder or water cylinder, so as to render same pressure in bilateral compartments separated by the piston. The max protrudeable length of dummy ends should be at least the same length of respective cylinder, so as not to expose the shaft hole while the end is fully retracted inwards.

[0170] More materials for the shaft and sealant parts plus more machining jobs are needed for such an embodiment, but it is still worthwhile in many occasions.

[0171] Although given a name dummy ends, it is still the user's free choice to assign those ends for whatever purpose, such as to actuate a position switch, to drive some auxiliaries, etc.

[0172] This embodiment can allow partial wet application.

Description on FIG. 3

[0173] FIG. 3 shows a DIY choice to build a pressure transformer with interface of aqueous solution and hydraulic oil, by using market most abundant regular hydraulic cylinders. In contrast with previous embodiment, it uses 4 cylinders in total, one more than previous.

[0174] With the marked all parameters, the shaft will go downwards, now this force equation is true:

P.sub.1*??.sub.1.sup.2/4=P.sub.2*?(?.sub.2.sup.2??.sub.3.sup.2)/4

or the hydraulic oil pressure for output:

P.sub.2=P.sub.1*?.sub.1.sup.2/(?.sub.2.sup.2??.sub.3.sup.2)

[0175] The solution cylinders can only be pressurized unilaterally, thus just unplug the upside holes, and hose the downside holes to the mutual-switching membranes modules.

[0176] Although it is not recommended by all manufacturers to use commercial available hydraulic cylinders with aqueous solution, anyway, the subject inventions encourage this trade-off choice, because hydraulic cylinders are usually not expensive, and other hydraulic products are not supposed so, thus even periodic replacement of those rebel cylinders is easy and affordable.

[0177] The hydraulic oil cylinders render different pressures across 2 sides of pistons, because of different liquid contact area, however this differential does not affect hydraulic power output.

[0178] The 2 rod-less compartments of the 2 cylinders are connected together, and prefilled enough hydraulic oil, so as to make sure: if one piston touching the bottom end, then the other piston will touch the top end. Obviously the oil in these 2 compartments is seclusive, isolated with the oil that is in the opposite compartments and directly output hydraulic power.

[0179] This embodiment can also allow partial wet application, i.e. only the osmotic partition submersible, and the hydraulic partition can stay dry.

[0180] Until hereby, 3 different forms with same function are rendered, though not all possible forms are exhaustively enumerated, as others may be too complex, such as this undrawn form: 2 parallel gear bars aka racks meshed with a central idle gear or pinion, and every rack is used as reciprocal shaft with its rest section connected to a piston of osmosis cylinder.

Description on FIG. 4

[0181] FIG. 4 shows the equivalence between a liquid DC-AC plus pressure transformer and an electric DC-AC plus voltage transformer. It contains only 2 sub-figures for contrast.

[0182] Sub-figure 4a is the fluidic version with embedded PRO. While the solution osmotic pressure is retarded in one compartment, by the hydraulic load in the transformer secondary coil, the pressure in opposite solution compartment will be grounded to atmosphere and gently squeezed out. Because retardation & squeeze events occur in 2 places, thus one tandem of 2 electromagnetic valves is needed to turn on simultaneously. When alternating to another half cycle, another tandem of 2 valves is supposed to turn on and previous tandem turns off. Once whole cycle is done, next cycle continues, so as to output ongoing AC hydraulic oil power.

[0183] For drawing convenience, there are 2 tanks in this sub-figure, however only one tank exists. In analogy, the tank is equivalent to the grounding concept in electric domain.

[0184] Sub-figure 4b is the equivalent electric version. The conventional voltage transformer comprises the primary 2 coils and secondary coil as output. In primary aka input side of the transformer, there is a simple half-wave DC-AC convertor. The input is DC voltage, it is alternatingly sent to one of 2 coils wired in serial, by the 2 thyristors, and the joint point of the 2 coils is grounded as zero volt reference.

[0185] Both versions need switching signal to trigger valves or thyristors in proper timing logics, and this is usually executed by a logic control module. A computer could be used for this purpose.

Description on FIG. 5

[0186] FIG. 5 shows a hydraulic rectifier and its electric equivalent circuit. It contains only 2 sub-figures.

[0187] Of which, the sub-figure 5a illustrates a bridge-style hydraulic rectifier that simply comprises 4 hydraulic check valves. The pressurized oil always flows out of the marked port P+, and returns to the port P? without exception, but anyway, the marked bidirectional hydraulic pump can infuse oil in any random direction while the pressure polarity of output hydraulic current can still keep invariant.

[0188] In a sense, it is just like as a high fidelity translation of the classical electronic bridge-style rectifier consisted of 4 diodes, and the sub-figure Sb just shows its circuit that can also be seen in all relevant basic textbooks.

[0189] As long as people can understand the simple electronic version rectifier, inspired by analogy, they can automatically understand how the mechanic version rectifier works.

[0190] Some electronic factories encapsulate 4 properly wired diodes into a compact single rectifier component; therefore, the same trend will prevail soon to fabricate the whole piece fluidic rectifier with 4 embedded check valves, if its applications become popular.

Description on FIG. 6

[0191] FIG. 6 shows a DC to AC inverter for hydraulic oil and its electric equivalent circuit. It contains only 2 sub-figures.

[0192] The pressurized oil current cannot change or alternate its flow direction at high frequency like its electronic counterpart AC current, because of inertia and oil hammer effect, that is why all market available hydraulic pumps are the type of DC.

[0193] Yet in subject inventions, a slowly alternating oil current hydraulic pump is a must-have in order to reciprocally drive the reverse osmosis process in the similar or same unit that is used for forward osmosis retarded power generation.

[0194] The sub-figure 6a shows a method to convert a normal DC hydraulic pump into a general oil AC power supply, just similar to a DC-AC electricity power inverter.

[0195] There are 4 electromagnetic hydraulic valves in this hydraulic DC-AC inverter. They teamwork in 2 pairs, and each 2 valves in diagonal positions must form a pair that is synchronously controlled. When one pair is turned on, the other pair will be turned off, so as to generate the alternating oil current. The NOT-gate component can properly drive the 2 pairs of valves.

[0196] The sub-figure 6b is just the equivalent circuit, but in electron current version. Instead of electromagnetic valves, there are 4 thyristors that harmonically work together to complete the DC-AC conversion. The NOT-gate component can properly drive the similarly paired thyristors.

Description on FIG. 7

[0197] FIG. 7 illustrates the masterplan of duplex pressure retarded osmosis power system.

[0198] In this figure, there are mainly 3 subsystems: pool or pond subsystem, wet subsystem and dry subsystem. The left side large shaded rectangular area with 4 round corners is the pool (sometimes may referred as panel or pond) subsystem; all components inside the pool constitute the wet subsystem; all the remainings constitute the dry subsystem.

[0199] The pool and wet subsystems are well detailed in previous paragraphs, further, another visible feature is still worthy to mention: unlike in the first figure, herein no pins to couple the solution-side shaft and oil-side shaft, the single shaft is common for all pistons and inserted into all liquid compartments, obviously not a DIY version, but a whole unit that is the preferred choice of those interested manufacturers.

[0200] Of course, though undrawn, the DlYers or contractors can still use 2 solution cylinders and 1 oil cylinder, then pin together to build the wet unit with equivalent function.

[0201] If the osmotic to hydraulic pressure transformer employs the embodiment drawn in the FIG. 2 or FIG. 3, then the wet unit can be partial wet, and its hydraulic partition can be dry, so as to extend its life expectation.

[0202] The dry subsystem can be further divided to 3 functional modules: hydraulic power generation, electric module of timing+sensing+valves controlling, and the freshwater plumbing circuit.

[0203] The hydraulic power generation module comprises a rectification assembly for alternating oil current, a hydraulic accumulator, a hydraulic motor and an electricity generator. High strength hydraulic hoses must be used anywhere inside this module to connect different parts: 4 check valves, motor, accumulator, and may include hydraulic tank if opted. Two pieces of hydraulic hoses bridge the wet subsystem and this module together.

[0204] The electric module comprises a logic controlling circuit, rechargeable auxiliary battery, and cables for sensor data acquisition and valves (and pump in some variant settings) governance.

[0205] The low pressure plumbing module provides freshwater for the high concentrated solution to suck through the semi-permeable membranes in osmosis rationale. In principle, osmotic pressure is just negative chemical potentiality, thus the underground water will be exerted negative pressure, and that is why needless of a pump for lifting to the osmotic-hydraulic pressure transformer soaked in the inground pool.

[0206] Although freshwater is the best choice in the plumbing module, however it is never a hard requirement, even brackish water or seawater is allowed, as long as the pooled solution is far concentrated than the plumbing side.

[0207] For example, in the Israel, both regular seawater & quasi saturated salt water are accessible: the former in the nearby Mediterranean Sea, the latter in the nearby Dead Sea, but freshwater is very precious, therefore, an alternative system still works even the plumbing module is hooked to the Mediterranean Sea, as well as the Dead Sea is used as the perfect saturated solution reservoir, because the salinity differentia in such a system is still great enough!

[0208] There are 2 solution compartments for osmosis in the wet subsystem, and they are working in alternating mode, thus the plumbing module must split the main conduit of water source into 2 branches, so as to feed the separative compartments. A drilled well and aquifer are drawn about the left top corner of this figure, and the plumbing module should also be switchable to other water sources, e.g. tap water supplied by local municipality, or river water if permitted.

[0209] Although the system can be shutdown if weather not favorable, anyway, as an option, a reverse osmosis scheme is drawn in a functional box so as to use the hydro grid power during the off-peak time in advantage of cheap rate. Its details will be briefed in next figure. The relevant valve 5 should turn off, if reverse osmosis is in action.

[0210] The concentration meter in the pool is mainly conserved for the RO subsystem, so as to judge whether the solution is too dilute because of too bad weather, such as foggy days or too cold.

[0211] In equivalence, even a simple lever sensor for realtime measuring pool depth can be used as concentration meter. As the osmosis concerned concentration is in unit of molarity, i.e. moles per liter, and the pool area is constant, thus the volume is in linear relation with level or depth reading, in turn, the concentration is proportional to the depth.

[0212] As long as the initial level is marked as the height or depth coordinate h.sub.0 which corresponding concentration is the saturated value C.sub.0, then there is a math function for the concentration at any level C(h)=C.sub.0*h.sub.0/h, here h>h.sub.0, otherwise, salt grains will precipitate.

[0213] The cylinder volume and dimension can be determined mainly by the required reciprocal period, power rating, allowable safe rod velocity. The guidance of design favors in small size with performance as first consideration.

[0214] All electromagnetic valves and electric switches are controlled by the electric module that functions as the system brain and may be implemented with a computer. As to the wiring, the afore-described FIG. 4 does illustrate the control circuit. In fact, it is the first stage of whole system, and just a DC to AC inverter with different isolated liquids, plus a pressure transformer.

[0215] Overview on this masterplan figure, wonder may rise: now that the pristine osmotic pressure is DC, the hydraulic motor is DC, why must this invention complexly sandwich an AC in-between to form DC-AC-DC chain?

[0216] The reason: because human lives in a limited time and space, despite of limitless infinite cosmos, but all DC procedures tend to exhaust the time and space in only one direction, e.g. if drive a piston by DC force forever, then infinite one dimension space will be needed, thus DC is not sustainable, unless cycling DC into AC. As to the DC motor, DC is just the input, and its shaft rotation is the final AC output.

[0217] Although it could be tried only to use the simplest one DC fluid circuit, e.g. a huge size solution container with one hose to osmosis membrane high pressure side and another hose to DC solution high pressure motor, however it is neither feasible nor economic because the huge solution container must endure pressure as high as 500+ times atmosphere, and also be subject to erosion, and such an expensive container is never acceptable. Nevertheless, if a regular hydraulic motor is not using the prescribed oil, but the erosive solution, then the frequent change of expensive motors will cost a fortune!

[0218] Therefore, the multiple times DC-AC change link is the best trade-off choice, as it enables the high pressure compartments as small as possible, as well as decent performance.

[0219] It is very important to emphasize that this masterplan can also stands for an osmosis battery system as long as simply replacing the pool with either a stationary or mobile tank, and it is unnecessary to redraw a reduplicate figure that would be almost same but with a new label.

[0220] In conclusion, most genius inventive points are manifested by this figure of masterplan: i. transmitting osmotic pressure to hydraulic oil pressure; ii. creating alternating oil current that carries energy in a similar way like an electric AC power supply; iii. converting oil AC into oil DC by a fluidic rectifier that simply comprises four cheap check valves; iv. smoothing the oil DC output by accumulator like an electrolytic capacitor; v. driving a hydraulic motor by the oil DC; vi. driving an electricity generator by the hydraulic motor.

Description on FIG. 8

[0221] FIG. 8 shows the duplex reverse osmosis subsystem.

[0222] This figure is just drawn by modification on previous masterplan figure, and most graphic elements are not changed, except abstraction of hydraulic power generation by a functional box, as well as emphasis on reverse osmosis key parts.

[0223] For concise, all reduplicate labels are removed, even though, it is still easy to identify any untagged component by familiarization with all previous rich-tagged figures.

[0224] The upmost important drawing elements are those parts relevant to the reverse osmosis subsystem: the 4 electromagnetic valves for hydraulic DC-AC oil current inverter, the regular hydraulic pump, the electric motor, and the logic control hosted by the controller for the hydraulic inverter plus the peripheral valves of solution compartments.

[0225] It is acceptable to use same wet unit for the reverse osmosis, and better to have another pair of hydraulic ports for driving reverse osmosis, though it is also possible to share one pair of hydraulic ports for both PRO & RO, as long as a pair of 3-way fittings are there for split.

[0226] The hydro grid power is used to run the electric motor that in turn drives the hydraulic pump. As a profitable choice, it is better to do reverse osmosis during off-peak time with cheap rate, if bad weather lasting too long time.

[0227] If wet unit is shared, as membrane is same, in order to get same RO flow rate, the net pressure after deduction of osmotic pressure should be the same with PRO, therefore the hydraulic pressure should equal twice of osmotic pressure, but such a double may exceed the rated pressure of a regular hydraulic pump.

[0228] To avoid above dilemma, it is better to not share, but to use an independent similar wet unit, so as to install the dedicated low resistance RO membranes for high flow rate & fast operation. To match this new wet unit with hydraulic pump, its geometry should be recalculated from equation: P.sub.2*(?.sub.2.sup.2??.sub.3.sup.2)=P.sub.1*?.sub.1.sup.2, where P.sub.1 is the sum of osmotic pressure plus RO net pressure, P.sub.2 pressure for common hydraulic components, the rest 3 diameter parameters just the same definition like the PRO wet unit.

[0229] If using another wet unit for RO, the controller should be reprogrammed to support it for properly controlling all new set of relevant valves, and the plumbing subsystem must also be adjusted for dispose of RO output freshwater. Of course, the generated freshwater is drinkable, thus it is unnecessary to dump all into well or top soil.

[0230] The RO subsystem is optional, so if hydro grid is unavailable or no special discount for off-peak price, just only invest for the PRO system, and use it when good weather & abide if bad weather.

[0231] There should be an algorithm to govern the switching between PRO & RO, especially if they share the wet unit, and it will be briefed in later figure.

Description on FIG. 9

[0232] FIG. 9 shows the timing of valves, assuming the power output is constant. It contains only 3 sub-figures.

[0233] The wet unit or so-called reciprocal syringe is supposed to work at accurate pace for converting osmosis power to hydraulic power.

[0234] The sub-figure 9a shows the dynamic position of the wet unit's common shaft with time elapse within a full period, and the position=0 means the center position while both compartments hold same volume of solution. The L denotes the max run length of the shaft between the coordinate valve ?L/2 and +L/2.

[0235] Sub-figure 9b shows the status change of the valve #1 and #4: OFF during the first half cycle and ON in the next half cycle.

[0236] Sub-figure 9c shows the status change of the valve #2 and #3: ON during the first half cycle and OFF in the next half cycle.

[0237] The valve of position is reported to the controller by the position sensor, and the controller decides when to turn on or off any relevant individual valve.

[0238] In fact, if the power output is not constant, or loads are changing, every single period may display different position-time curve, and valve states corresponds synchronously.

Description on FIG. 10

[0239] FIG. 10 shows the pressure curve charged on the hydraulic motor.

[0240] When the hydraulic motor is working hard to output energy onto loads, the oil pressure inside hoses will change, though the associated hydraulic accumulator can smooth the pressure. The pressure curve looks like sawtooth, and minor pressure oscillation usually does not affect the operational stability.

[0241] In the analogous electronic version, the unregulated immediate output of AC-DC rectifier also shows similar ripple waves on the paralleled capacitor, though a modern switching DC power supply can output very stable voltage with smart feedback-regulated circuit.

[0242] The tooth height reflects the pressure drop ?P, and generally speaking, it is proportional to the loads duty & concentration drop ?C during the osmosis progression in a solution compartment.

[0243] The ?C is roughly determined by the (L/H)*C, where L is the max stroke length of the shaft, H the height before a fresh charged solution starts osmosis, and C the original concentration.

[0244] Usually, the ?C/C or L/H in a good design is less than 10%, so as for basic stable pressure output. The smaller the ?C/C, the higher the stability & robustness, but too small will see high frequent reciprocal shaft motion that may quicken the wearing and even deteriorate system performance because of fluidic inertia & switch delay of valves; otherwise, too big will see an unstable and weak output, and it is also not necessary because the soaked wet unit can conveniently discharge the diluted solution & recharge high concentration solution by quick diffusion with a little overhead energy consumption on those electromagnetic valves.

[0245] With assistance of the shaft position sensor, it is possible to adjust the L & H parameters in a reasonable range, so as to match the pool size, weather condition, and loads capacity.

Description on FIG. 11

[0246] FIG. 11 shows the program flowchart of PRO and RO switching algorithm.

[0247] It reflects following algorithm:

[0248] If the concentration meter reports NORMAL condition, then let business as usual, i.e. continue osmosis power generation, else alarm a warning of TOO LOW, and if now is the off-peak time of hydro grid, then after turn off the valve 5 and turn on the switch 10, start the reverse osmosis job, else turn off all valves & switches, thenafter, pause both power generation & reverse osmosis, and simply recheck whether the weather getting better or wait until off-time becomes ready. Such a loop of processes will go on and on.

[0249] More valves and switches must be properly reset as the preparation job for restart of PRO power generation: turn on the valve 5, turn off the valves 6, 7, 8, 9, and the switch 10 also needs to be turned off, so as to stop the electric motor.

[0250] To optimize controller performance, it is a good practice to set 3 timers for state check, the first timer is for the osmosis power generation, the second for the reverse osmosis, the last for the pause-then-wait.

Description on FIG. 12

[0251] FIG. 12 shows the salt solution pool or pond with wall-less dog-height transparent coverall roof. It contains only 2 sub-figures.

[0252] Although full open air is good for evaporation, perhaps a spell of rain may undo many days effort of evaporation. A roof can fix the worry, however it must be transparent, so as not to shield the important sunshine; and walls can block winds or vapor flow, so do not enclose the roof with walls, so as to let winds assist evaporation and blow away vapor.

[0253] To minimize this structure, just let the height as low as reasonable, even the height can just let dogs walk under the roof. Even truss-less roof could be acceptable, because of its light duty.

[0254] The sub-figure 12a is a bird view of sample pool settings. It shows the roof, pillars, an array of vent ports, the under salt solution pool, and the submersible osmosis unit plus the peripheral hoses & cables that leads to the undrawn dry units.

[0255] In usual, polycarbonate is recommended for roof material, because of its high transparency as well as the great mechanic strength.

[0256] Sub-figure 12b is the view of cross section vertical to the ridge. It shows the levee, the black plastic liner, the soil, the submersible osmosis unit, hoses, cables, and how shallow the roof and solution depth.

[0257] The recommended depth is about 3 to 10 centimeters, but not limited to if users prefer deeper. As the average economic depth may not be enough to soak entire wet unit, thus a localized pit within the pool should be dug, so as to provide the wet unit with accommodation.

Description on FIG. 13

[0258] FIG. 13 shows the alternative pool configuration that is purposed for those windy districts to cubically maximize the utilization of winds energy as well as to occupy less land.

[0259] It features a stacked matrix of evaporation trays over a pool. In this figure, only 4 layers are drawn, but the real choice for an individual project can be any number of layers.

[0260] A sturdy rack structure with a plurality of layers is needed to hold all raised and connected trays. The plumbing connection can enable every single tray to hold same height of liquid, and automatically equalize all trays.

[0261] The pool depth should be mildly deeper than regular pools discussed in previous description, because it needs to hold the full volume of solution in case of emptying all trays. Because the bottom pool can retract all solution, thus the roof is dispensable, but the tray catchment should be diverted away with reasonable distance, though the divert pipe is not drawn.

[0262] There is a drainage short pipe underneath every layer, and it is governed by an electromagnetic valve, so as to empty any or all layers in occasion of maintenance, or to remix entire solution if there is significant discrepancy of concentration in different layers caused by the unequal evaporation rate during relative long time operation.

[0263] Generally speaking, evaporation rate on the top layer may be mildly larger than the rest trays, because top layer can always receive more solar sunshine. If winds effect dominates, the small discrepancy could be ignored, otherwise, remixing may be needed after a critical point reached.

[0264] The method to remix is: drain all trays to empty, and then turn off all drainage valves, pump liquid from the pool to the tray on top layer, until all trays reach same height, turn off the pump.

[0265] A level sensor can be installed in the pool, so as to judge whether a remix job done. The marked sensor can also detect the liquid fall from the marked overflow port in this figure, because liquid will flow out of the port if all trays are full.

[0266] A properly timed periodic pump job can almost get equivalent effect to a full remixing process, because it circulates the solution and results in mix effect in some extent, though not perfect.

[0267] With this pool and the stacked trays, the afore-preferred wet unit can no longer have to be submersible, as the concentration in pool may be lower than the top tray because of less sunshine, but in order to let it stay dry, the following modifications must be done: i. Open both feed port and exhaust port in all solution compartments; ii. Govern all new added ports by new added electromagnetic valves; iii. Connect feed ports to the top tray, and exhaust ports to the pool; iv. Deploy the unit on a table with about half height of the rack of trays, so as to utilize gravity for both recharging fresh solution and discharging exhaust solution; v. Adjust the program code to manage all new added valves, the remix pump and the level sensor.

[0268] It is also possible to still keep the osmosis unit submersible, but the remix process should be run frequently, so as to overcome the disadvantage of diluter solution at the lowest position, in turn, the system will consume extra energy. This situation is not drawn in the figure.

[0269] In fact, even with the regular pool without the overhead trays, it is also feasible to change the so-called wet unit for dry stay, as long as there is no problem to spend more money in new added valves and pumps.

[0270] Because minor leakage from the rim of solution-faced piston is allowable and tolerable as an engineering trade-off, therefore, if the osmosis-hydraulic pressure transformer unit is exposed in atmosphere, the ugly leakage may be an eyesore, and a dripping catch pan is better placed under the unit if the user cares, then the caught solution can be diverted to the pool. This optional gadget pan is also not drawn in this figure. Of course, for the submersible unit, this is never an issue, because the minor leakage is invisible.

[0271] As to the solution depth in each tray, it depends on the local diurnal temperature, the higher the temperature, the shallower the solution can be.

Description on FIG. 14

[0272] FIG. 14 illustrates the quasi closed local water circulation. It contains only 2 sub-figures. Presented by courtesy, this figure is just a bonus to incent peers better understanding subject inventions. Even without this figure, the detail description is still complete.

[0273] In sub-figure 14a, a closed water circulation shows how the natural evaporation-precipitation endless cycle is used as smuggling vehicle for osmosis energy harvest with subject inventions.

[0274] The salt water panel or pool serves the osmosis power generator with naturally concentrated solution, and simultaneously serves as a dump site for exhaust solution of the same generator.

[0275] The soil serves as a tremendous precipitation buffer for receiving, seeping and drawing.

[0276] The solar and wind energy fuels the evaporation, as well as the atmosphere heat engine serves as a condenser for precipitation.

[0277] In sub-figure 14b, a proportionally segmented circle suggests the best practice to maintain a quantitative balance: evaporated water =precipitated water =osmosis used water, when taking advantage of water circulation for osmosis power generation.

[0278] Of course, it is not mandatory for all PRO applications with subject inventions, as even the Great Nature cannot guarantee the equality of evaporation and precipitation at some local zones. Letting osmosis water usage match local precipitation may be realistic for those wells water users, but those riverside users or tap water users can surely plan whatever project size as long as they have abundant disposable land for solution evaporation.

Description on FIG. 15

[0279] FIG. 15 illustrates a masterplan to use the osmosis-hydraulic system as a huge capacity battery for vehicles and storage device for other renewable energy sources.

[0280] It no longer allocates land lot for evaporation pool, but for the photovoltaic panel array, so as to take advantage that the PV panels can output more power than the salt panel per unit land usage, despite the cost will increase significant percentage.

[0281] Instead of a large surface pool, large volume tanks are used, and tank's surface area can be minimized if wish by proper geometry design, because of no longer natural evaporation.

[0282] During shiny days, the PV panels output hard to drive electric motor for reverse osmosis. The conventional expensive DC-AC inverter can be eliminated for cost saving, as a DC motor is more convenient to drive the hydraulic pump and the oil current DC-AC fluid inverter that is packed in the so-labeled RO dry unit, in turn, the dry unit drives the so-labeled RO wet unit that is submerged in the salt water tank, so as to concentrate the solution by reverse osmosis and feedback water into well or dedicated freshwater tank if a well unavailable. There is a sign of switch in the figure for indication of water supply router choice.

[0283] During windy days, a wind turbine can also output electricity, and in a joint RO effort, it behaves similar to the PV panels in next series of actions.

[0284] During those times that are cloudy or night or windless, the hydro grid can be a RO helper, as long as the cheap off-peak price is enabled.

[0285] The PV and wind powers are given with the highest priority, the least for the hydro grid, so as to maximize the green energy utilization for RO recharging the osmosis battery system.

[0286] As to the consumer side, the energy in the battery can either be used online by its owner, or sold to the hydro grid during peak demand time for good profit. There are 2 ways for using the energy in situ, one is send into house for appliances, the other is used as backup special fuels to accommodate the demand of mobile machines with osmosis engines, such as those special built tractors, forklifts, etc.

[0287] Future tractors or the likes can be equipped with pure osmosis batteries. Those machines usually run in short range shuttle, and easy return for refueling, thus the demerit of low energy density can be avoided. Hybrid power of osmosis plus diesel engine is also possible.

[0288] Not like the daylong recharge for an electric vehicle, the refueling moment is very short, just simply dump the exhaust solution to the solution tank, wait a moment, then pump from the same dump point to refill the machine, or if pump from another far point of the same tank, there is no need to wait for diffusion, just immediately refill after dump.

[0289] To make sure the refilled solution concentration high enough, the volume of the stationary battery tank should be far greater enough than the tank of mobile equipment, otherwise the exhaust solution may significantly dilute the stock solution.

[0290] While refilling, do not forget the water tank, and it is too simple to worth a mention.

[0291] To adapt the household appliances, the output electricity should comply with local hydro standard for correct voltage and frequency. If let the hydraulic motor drive a DC generator, then it will be troublesome, because a DC-AC inverter has to be inserted, therefore, as a best practice, a standard AC generator is recommended to be coupled with the hydraulic motor.

[0292] To maintain electricity quality, the fluctuation of osmotic pressure is better controlled fewer than 10%, therefore float RO charging the battery is preferred, otherwise, an electronic conditioning or stabilizing module should be used, and this may also be required by hydro companies for feeding into their grid network.

[0293] In the figure, a function block is labeled as hydraulic power unit, and it comprises a hydraulic accumulator, a hydraulic motor, an AC electricity generator and a set of 4 hydraulic check valves that function as oil current rectifier. The input of the fluid rectifier is hosed to the so-labeled PRO wet unit that is submersed and shares the water supply with RO wet unit.

[0294] Because of the design without evaporation, thus theoretically, both water and the salt or other solute are conservative, though casual small replenish may be needed.

Description on FIG. 16

[0295] FIG. 16 illustrates how to deploy the osmosis power plant in desert area, as well as gradually change it into a wonderful oasis. The sea salt production is reserved as a supplement.

[0296] The drawn pumps are key samples, yet there are more undrawn pumps installed in those midway relay stations along the transportation pipeline. Also, the drawn 6 valves are inlined at key points for control and management, but not limited to, more valves may need if necessary.

[0297] The incoming seawater firstly fills in the so-labeled seawater lake via the main valve. There are 3 outlets around the seawater lake: one is to fill the evaporation pools for making saturated salt solution, next is to fill the reserved pools for sea salt grain production together with the RO freshwater production line, and the last is to fill the osmosis partition of the submersible unit.

[0298] After the concentration in the evaporation pools reaches the max, discharge to the so-labeled saturated salt lake for storage and PRO power generation, then refill for next saturating cycle.

[0299] During power generation, the concentration in the saturated salt lake will be slowly diluted, and the restless evaporation on the lake is supposed to anti-dilute until equilibrium. If the lake evaporation is not enough, the submersible pump should send solution back to the pools.

[0300] The interface hydraulic hoses of the wet unit are deployed to connect the onshore dry unit that is labeled as power house, and then hydraulic power is converted into electricity. As a great powerplant, most energy are transmitted to outside customers via hydro grid network, minor energy is consumed onsite.

[0301] The major onsite energy consumer is the RO freshwater production line, and Its 2 dump paths are labeled as dump A and dump B, choices are case dependent.

[0302] This drawing is just for illustrative purpose, not for accurate dimension scale, and the square count of any pool cluster is only symbolical, not real number.

REFERENCE

[0303] 1. Energy production at the Dead Sea by pressure-retarded osmosis: challenge or chimera? By Sidney Loeb, Desalination 120 (1998) 247-262, DOI: 10.1016/S0011-9164(98)00222-7 [0304] 2. Method and apparatus for generating power utilizing pressure-retarded-osmosis, U.S. Pat. No. 5,390,6250 [0305] 3. Semi-permeable membrane for use in osmosis and method and plant for providing elevated pressure by osmosis to create power, U.S. Pat. No. 7,566,402 B2 [0306] 4. Hybrid RO/PRO system, U57871522 B2 [0307] 5. Osmotic energy, U.S. Pat. No. 8,099,958 B2 [0308] 6. Utility scale osmotic grid storage, U.S. Pat. No. 8,795,525 B2 [0309] 7. Method and apparatus for osmotic power generation, U.S. Pat. No. 9,023,210 B2 [0310] 8. Osmosis battery & high magnetic field generator & superconducting ionic current loop, U.S. 15848097

[0311] All inventions herein contain key implementing methods and preferred embodiments, and may be flexibly embodied in other specific forms or consisted of different geometry or other configurations without departing from its spirit or essential characteristics.

[0312] To succinctly express claims, hereby repeat the most useful 2 abbreviations: DCDirect Current, i.e. nonreturnable motion and ACAlternating Current, i.e. returnable motion, both DC & AC can generally characterize anyone of electrons stream or ions stream or neutral fluid (e.g. aqueous solution, hydraulic oil, even solid or gas) stream, and the solid stream is identical to solid motion, such as shaft or rod motion. Rotational & reciprocal motions are regarded as AC.

[0313] Osmosis or reverse osmosis involves respectively mixture or separation process of two liquids with concentration differential. The low concentration liquid can be just water, but not limited to; for convenience, the counterpart high concentration liquid refers to the working solution.

[0314] Although above text in this page are not numbered or itemized, the legal effect does hold on par with all the rest numbered claims.