CN102597513A

CN102597513A - Liquid metal heat storage system

Info

Publication number: CN102597513A
Application number: CN2010800485820A
Authority: CN
Inventors: 阿隆·J·洪特
Original assignee: Individual
Current assignee: THERMAPHASE ENERGY Inc
Priority date: 2009-09-10
Filing date: 2010-09-09
Publication date: 2012-07-18
Also published as: WO2011031894A3; WO2011031894A2; US20110120669A1; EP2475886A2

Abstract

Embodiments of the present invention relate generally to high temperature thermal energy storage and, more particularly, to receiving heat from and providing heat to a gaseous medium using the latent heat of fusion of a molten and solidified metal. Embodiments of the present invention are also referred to as liquid metal thermal storage systems or LIMETS. Also described are methods of containing the storage material, heat transfer devices, and choices of metals and alloys for the heat storage material.

Description

The liquid metal heat reservoir

Background technique

Seeing that to a great extent by the problem of carbon dioxide, methane and the absorbing particles global warming that release caused in atmosphere and the increase of fossil fuel, the generating of using solar generator to be used for the public utilities scale causes public attention once more.Using focused solar energy that working fluid is heated to high temperature provides for using the attractive of fossil fuel to substitute with the electrical production that is used for the public utilities scale with the machine power that operate generator is provided with operation Rankine (Rankin) cycle engine, Bretton (Brayton) cycle engine and Stirling (Sterling) cycle engine.But public utilities require the electrical production facility on annual 75% grade, the electric power that can provide and deliver to be provided usually.Because only 50% the time of the sun on the year basis is positioned on the horizon, the storage that therefore is necessary certain form is provided is with manipulator when not having sunlight.

Thermal energy storage can realize through the hot form that energy is stored as as sensible heat or latent heat (or their combination).Present solar collector utilizes heliostat, parabolic wire casing or linear Fresnel (Fresnel) reflector focuses sunshine on solar receiver.These receivers are by the focusing sunlight heating and utilize steam, oil, liquid salt, liquid base metal or gas to collect and transmit fluid as heat.This fluid can self can be delivered to another medium so that storage to be provided as hot storage medium or heat.Like what discussed by Geyer in Winter etc., heat accumulation can be provided by the sensible heat in oil tank, oil and rock, liquid salt or the liquid base metal.Fluid by the focusing sunlight heating is used to produce steam, and heated working fluid is to be used for transformation of energy, and perhaps they can at high temperature store (or combination).With after being used for transformation of energy, the fluid and the hot fluid of cooling are stored discretely at the heat that discharges them.This can realize in hot jar and cold jar of separating or pass through to use the structure of thermocline to realize.In the thermocline system, colder (density is bigger) fluid forms bottom and hotter (density is less) fluid formation upper strata.In in these structures any, when the sun does not provide heat, the hot liquid of being stored can be drawn through heat exchanger with heated working fluid with the cold side that is used for electrical production and arrives at memory section subsequently to accomplish circulation.

Alternatively, latent heat of fusion can be used to store heat energy.In heat reservoir, used liquid salt or liquid base metal, said liquid salt or liquid base metal stand phase transformation with storage or release heat under its melting point.The advantage of the heat storage of this form is that heat is almost discharging under the stationary temperature, thereby is provided for the optimum operation condition of energy conversion cycle.Another advantage of using the storage of latent heat energy is owing to can significantly reduce the amount of storage medium.For the purpose of clear and definite, the amount that is stored in the energy in the specific heat is confirmed by the product of specific heat and temperature variation.For example, specific heat of water is 1cal/gm, if temperature reduces by 1 ℃, then a gram water discharges 1 caloric heat.Alternatively, the latent heat of fusion of water is about 80cal/gm, makes that under stationary temperature almost, freezing or solidify the energy that a gram ice discharged is 80 caloric heats.The amount of the water that needs through the heat that freezes a gram ice and provide the storage same amount thus, is 80 times of 1 ℃ of change water temperature.

In using the latent heat storage system of high temp. salt, owing to there is the restriction that heat is flow to and flows out storage medium in the lower thermal conductivity of salt.This is further aggravation by the following fact: when the heat storage discharged, salt freezed around the pipe that carries heat-exchange fluid, and this stops convective heat transfer.This has reduced from storage system, to extract the speed of heat.Thus, the lower thermal conductivity of salt and the convection current that causes owing to the illiquidity of salt are cut down together to utilizing such latent heat storage system to constitute obstacle.

The another consideration factor is an operating temperature in the operation of solar power system.In order to make the focusing solar power generation system have cost efficiency as much as possible, expectation be the maximizing efficiency that makes energy conversion cycle.This has reduced the cost of the expensive components (focusing trap) of equipment.Because the maximal efficiency of heat engine by its heat reservoir of working betwixt and the decision of the temperature difference between the freezer, therefore it would be desirable under the highest possible temperature and operates.Oil decomposes being higher than under about 400 ℃ temperature.The most of heat reservoirs that use salt are operated being lower than under about 570 ℃.There is not to find effectively device storage steam under the required pressure and temperature of the efficient rankine cycle engine of operation.Bretton or gas circulation motor using gases are as working fluid, and storage gas also is unpractical under very high temperature and pressure.Brayton cycle provides the peak efficiency of the tower centralized system that is used to generate electricity, and this is because operating temperature is only limited by turbine-entry temperature (obviously above 1000 ℃).The storage high-temperature gas is not the energy storage solutions of reality.

Mode through reference is incorporated into

The full content of following reference is incorporated this paper into:

The name of authorizing people such as Terry D.Claar on April 23rd, 1985 is called the United States Patent(USP) No. 4 of " High-Temperature Direct-Contact Thermal Energy Storage Using Phase-Change Media " (" using the high temperature direct contact type thermal energy storage of phase change medium "); 512,388;

" the Comments on the Solubility of Carbon in Molten Aluminum " of Simensen (" commenting the dissolution rate of carbon in molten aluminum "), Metallurgical Transactions A, volume 20A, in January, 1989,191 pages;

Winter, Sizmann, Vant-Hull, Solar Power Plants (solar power plant), the 6th chapter, Springer, Verlag, 1991; And

Guthy and Makhlouf, " The aluminum-silicon eutectic reaction " (" aluminium-silicon eutectic peaction: mechanism and crystallography "), Journal of Light Metals, No.4, November calendar year 2001,199 pages-218 pages.

Summary of the invention

Embodiments of the invention relate to through melting and solidification or freeze metal and metal alloy with storage and discharge special metal and the high latent heat of fusion of alloy to be suitable for storing a large amount of heat energy under the very high-temperature of operating gas turbine or other purposes.Particularly, said alloy can by have melting point and eutectic temperature be in energy conversion device inclusive ranges to be used in two kinds or more kinds of metal constitute.

In first embodiment that this paper considers, said metal or alloy is contained in the array that is arranged at the pipe in the insulated channel, and wherein high-temperature gas circulates through said insulated channel.Said system is absorbed heat by the gas that passes through, and said gas is contained in said metal/alloy said pipe in through said pipe with heating and fusing from solar receiver or other thermals source.Said system undergoes phase transition (liquid is to solid) and temperature up to said metal or alloy and has dropped to the optimum working temperature that is used for system and heat release through making air to be heated pass same channels.

In another embodiment, said metal or alloy is contained in the insulating vessel, and said insulating vessel is equipped with heat transfer element or the pipe with said thermal source thermal communication.In this case, said system through will be in the passage of wall portion or path the heat of circuit high-temperature gas pass in the cavity that wall is delivered to holding solid/liquid metal or alloy and absorb heat up to said metal or alloy fusing.Said system is through seeing heat and heat release off the channel connection of wherein said heat transfer element or pipe and carrying gas to be heated from the cavity with identical or different heat transfer element or pipe.

In arbitrary the foregoing description, has extensive selection to employed alloy.In another embodiment, two kinds of elements combine to form alloy melting point to confirm that by the percentage composition that every kind of metal appears melting point is then selected according to required operating temperature.In specific embodiment, choose the alloy of forming by aluminium and silicon.Through changing the ratio of these elements, operating temperature can be chosen for from about 600 ℃ to 1411 ℃.This very wide temperature range provides the multiple turbine-entry temperature that is used to operate the upper range that comprises the Rankine vapor recycle.

In first embodiment, hold the pipe of metal or metal alloy and can process by pottery, metal or coated graphite.Under the situation of the air in heat exchanger or other oxidizing gas (for example, carbon dioxide), graphite must be coated in metal or the pottery, otherwise under the operating temperature that graphite will be considered herein through oxidated.

In the embodiment who uses the heat transfer element that heat transferred is encapsulated in the metal in the independent insulation cavity or from this metal, transmits heat or pipe, said pipe can by suitable high-melting-point solid metal for example the refractory alloy of copper, steel, nickel or these metals or other metals form.If minimum with the chemical reaction of heat storage metal or metal alloy, then said element also can be by forming with the graphite that molten metal directly contact, still possibly be exposed to suitably coating in portion's section of oxidizing atmosphere at graphite.

In another embodiment, the sealing hollow tube that these heat transfer elements or pipe also can be made up of high-temperature metal pottery or graphite holds and has little secondary element or the compound that boiling temperature is higher than the fusing point of metal or metal alloy storage medium.In this case, said element or compound boil by passing the gas that is positioned at the passage below the said storage tank in the underpart of said pipe, and the upper end portion embeds in the said metal or metal alloy storage medium.This heat pipe arranges it is heat exchanger very efficiently.In this case, heat accumulation is through similar pipe heat release, but this pipe holds and has element or the compound that boiling temperature is lower than the fusing point of said metal or metal alloy storage medium.The said lower end part of said heat pipe is in said metal or alloy storage medium, and said upper end portion is passed the upside in said storage chamber and got into the gas separated bearer path.In this case, heat accumulation passes said upper channel and heat release through making gas.

The latent heat storage of this form has some advantages.At first, most of heat discharges under steady temperature, and this allows that combustion gas turbine operates in its design temperature.This is that non-design operation owing to combustion gas turbine can significantly reduce its conversion efficiency and considers.The heat absorption of heat accumulation portion is realized under than the high any reasonable temperature of the fusing point of metal through gas.Because all suitable metals and alloy shrink when fusing, so metal has no reason to destroy its containing pipe or storage vessel.The high thermal conductivity that is in the metal in liquid and the solid form provides intrametallic fabulous heat transmission.This has been avoided the problem that in using liquid salt or alkali metal, run into, and wherein the lower thermal conductivity zone of solid and solidification material makes the release of heat slack-off.

Description of drawings

Under combining advantages during in the face of the description of example embodiment, the technician will easily understand aforementioned aspect and other.

Fig. 1 a is embodiment's the schematic top view of the heat exchanger of embodiments of the invention.

Fig. 1 b is embodiment's the schematic side view of the heat exchanger of embodiments of the invention.

Fig. 1 c is one a schematic representation in the pipe that holds metal or metal alloy of embodiments of the invention.

Fig. 1 d is the embodiment's of the vertical flow structure of a use of the present invention schematic representation, and wherein gas is parallel to the aligning direction motion of storage tube.

Fig. 1 e and Fig. 1 f have described the optional embodiment of pipe of the present invention.

Fig. 2 is the schematic representation of another embodiment of the present invention, shows heat absorption space that is positioned at and the heat release space that is positioned at metal or metal alloy storage vessel top.

Fig. 3 a is the schematic representation how embodiments of the invention are implemented under pure solar energy pattern through gas turbine engine.

Fig. 3 b is the schematic representation how embodiments of the invention are implemented during hot driving through gas turbine engine.

Fig. 3 c is the schematic representation how embodiments of the invention are implemented during married operation through gas turbine generator, and the power that wherein is used for turbine is supplied with by heat accumulation and solar receiver.

Embodiment

Under the background of the solar generator equipment of brayton cycle, embodiments of the invention are described.But the technician should understand easily, and disclosed material of this paper and method have the application under multiple other situation of expectation high-temperature heat-storage.

One embodiment of the present of invention are also referred to as liquid metal thermal storage system (LIMETS), consist essentially of four objects: the metal or metal alloy heat storage material; The pipe or the compartment that hold metal or metal alloy; Seal the insulation cavity of said pipe; And heat transfer medium (gas).Fig. 1 a is the plan view that the signal of system is drawn, and shows insulation cavity 100, the stoneware pipe that holds metal or metal alloy or coated graphite pipe 101 and insulating vessel 102.Fig. 1 b is the side view of same parts.Fig. 1 c is the pipe and the sectional view of metal, shows pipe 101 and metal 103 with open-top.Fig. 1 d has described this embodiment's perspective view.Only as an example, pipe 101 can comprise the surface area that makes pipe and to the heat transfer rate of pipe and/or the fin or other adjuncts or the structure (Fig. 1 e) that increase from the heat transfer rate of pipe.Pipe also has the cross section (Fig. 1 f) that increases heat transfer rate.This cross section is through for example comprising the star cross section and the surface area of increasing section.Pipe and closure are arranged to temperature and the characteristic of consideration gas transfer medium and make maximizes heat transfer.Reynolds numerical value is confirmed by the characteristic size of the character of gas and pipe and design should be optimized these factors so that to the heat transmission of pipe with from the maximizes heat transfer of pipe.

Fig. 2 illustrates another embodiment who utilizes pipe.The vertically-oriented of pipe is useful, so that utilize the gas that gets off from the solar receiver that is positioned at top of tower and provide optional design to optimize the heat transmission to pipe.The layout of conduit can allow that gas flows through vertical tube up or down.In these two kinds of layouts, system passes through to take place up to fusing from the solar receiver that is positioned at the pipe top through making hot gas, absorbs heat with this.Because most of metal and metal alloy expand when fusing, so the smelt of less dense will rise to the top, thereby the bottom is melted at last.This has the well-mixed of promotion to guarantee the almost effect of isothermal of metal or metal alloy.In this embodiment, metal or metal alloy 104 is contained in the insulating vessel 105 of separation, and this insulating vessel is via high heat conductivity metal bar or metallic cover graphite bars or preferably be communicated with heated air through using the hollow heat pipe part or managing 106 and 107.In this embodiment, be provided with two passages, a path 10 8 that is used for heat (filling heat) gas be positioned at the metal or metal alloy container below, and a path 10 9 is in the above.Hot gas passes lower channel 108 and heat pipe spare or pipe or bar 106 and heat is sent to metal or metal alloy with fusing storage medium 104.In order to make the heat accumulation heat release, heat pipe spare or pipe or bar 107 are sent to upper channel with heat when colder gas is drawn through upper channel like the category.Hot transmission can obviously improve through using heat pipe, and the element or the compound that wherein have suitable boiling point are encapsulated in the pipe.Only as an example, can comprise can be at the potassium that uses between about 500 ℃ to 1000 ℃, at sodium that uses between 500 ℃ to 1000 ℃ and the lithium that between 900 ℃ to 1700 ℃, uses for this element or compound.

Because heat pipe spare along upwards the direction transfer of heat is the most effective, therefore is provided with two

sleeve parts

106 and 107 in this embodiment.At following pipe fitting or manage element or compound in 106 and preferably be chosen for and have the operating temperature higher than the melting point of metal or metal alloy storage medium.At last pipe fitting or manage element or compound in 107 and preferably be chosen for and have the operating temperature lower than the melting point of metal or metal alloy storage medium.

Pass the underpart of the hot gas heating pipe of lower channel, and element in pipe or compound gasify and move upward and condensing than the cold end place in storage medium.When storage medium had melted and need heat with operating turbine, gas to be heated was drawn through upper channel.Last heat pipe spare holds and has element or the compound that operating temperature is lower than the melting point of storage medium.Thus, when being drawn through upper channel than cool air, element or compound in last heat pipe spare condense on the upper end portion, thus with heat transferred gas with the operation turbine.Heat is transmitted by gas flow control, and gas moves upward when the needs heat.Because upper channel can be under the different pressure with lower channel and storage medium need not be in the pressurized container, so this heat pipe spare system has extra advantage.Thus, system can obtain heat from the air under being in atmospheric pressure, is being used for storing heat and discharges heat under the convenient pressure of gas turbine machine operation.

Choosing of metal or alloy bar or pipe: 1) melting point by for example confirming as follows; 2) latent heat of fusion; 3) thermal conductivity; 4) its viscosity and thermoconvection characteristic; 5) expansion and the contraction during phase transformation; 5) with the chemical reactivity of contents with heat transmission element; And 6) influence of pollution impurity.For given application arbitrarily, melting point can be confirmed through selecting metal, perhaps regulate through selecting alloy more carefully.Other Considerations comprise crystallite dimension, pollute the influence of impurity and separate with the alloy between melt down again solidifying or freeze.The another consideration factor be metal or metal alloy the price on the metal current market with and future price when equipment is discarded, this is because this possibly mean great investment.

The pure non-alkali metal that can be used for heat accumulation comprise aluminium (m.p.660 ℃, l.h.95cal/gm), (m.p.1084 ℃ of copper; L.h.49cal/gm), and iron (m.p.1536 ℃, l.h.65cal/gm); Magnesium (m.p.650 ℃, l.h.88cal/gm) (m.p.=fusing point, l.h.=latent heat).Other pure metal have unpractiaca high or low melting point, are rare, costliness, radioactive or poisonous.But above-mentioned and alloys other metals can be formed for multiple especially type possible substitute of heat storage material.For this, reason is that two kinds of metals with different melting points usually form when being melted to together and have the low-melting eutectic mixture of fusing point than any metal self.These effects can be reduced to fusing point in the scope of the material that can be used in new metal alloy storage medium sometimes significantly.

Another embodiment of the present invention comprises the specific selection as the aluminium of heat storage material and silicon.Silicon is the common composition of aluminum alloy; Particularly in the component of AlSi12 (about 88% aluminium and 12% silicon and impurity in a small amount is iron for example).This is because physical property that it produced but particularly advantageous combination of materials.Silicon has 1411 ℃ fusing point although aluminium has about 660 ℃ fusing point, and the fusing point of the eutectic mixture of AlSi12 is about 600 ℃.Therefore, can find out that through changing component, the melting range of the alloy that is produced is 600 ℃ to 1411 ℃ for the pure silicon component from eutectic point.In the chart of the melting point that illustrates below this is shown in to component.This is to be used for the very wide of high temperature latent heat storage material and scope easily.

The equilbrium phase diagram that is used for the Al-Si system, the meta that shows liquidus curve and solidus is extended

This combination of materials has another useful advantage.Although the latent heat of aluminium is higher with other compared with metal the time, be 95cal/gm, it is 430cal/gm that the latent heat of fusion of silicon is in known highest point.For example, visible from accompanying drawing, at about 50-50 atom percent place, the melting point of mixture is about 1000 ℃.If the linear interpolation between the latent heat of fusion of use aluminium and silicon, the latent heat of the mixture that is then produced is about 263cal/gm.This is comparable to the latent heat of sodium, and wherein sodium has been used for the latent heat storage medium of 27cal/gm.(be about 1/10 of this mixture---need 10 times storage quality).Other potential storage mediums comprise having the zinc that latent heat of fusion is 27cal/gm, the copper of 49cal/gm or the lead of 5.5cal/gm.This shows, when using the AlSi combination, significantly reduced required material.

Another advantage of the combination of silicon and aluminium is: when having other compared with metal of suitable melting point, these materials have the industrial level that enough is used for this purpose, and cost is lower.

Another Consideration is the selection of containing pipe.The size and dimension of pipe should be chosen for and make through the maximizes heat transfer of gas and the melting rate and the pattern of optimization encapsulated metal.In some cases, can add radially or axial fin to improve heat transmission to pipe.Because the high melting temperature (600 ℃-1200 ℃) of related metal, thereby high-temperature ceramic materials is suitable.But some high temperature alloy pipes can be considered in the bottom of this temperature range, to be used to hold.Another selection of material is a graphite.Like what discuss by Simensen, graphite have high thermal conductivity and with the hypoergia of aluminium, and aluminium is widely used for electrode and holds material in refining.But graphite maybe be inapplicable when oxidizing gas (for example air or carbon dioxide) occurring, and this is because graphite will be oxidized to carbon dioxide and can not be as holding or heat-transfer arrangement.Graphite can be coated with metal or ceramic to prevent its oxidation.The selection of tube material should be instructed by the operating temperature of expectation and potential metal-containing pipe reaction.Pipe can be based on the selection of gas and metal but sealing or open wide.If air is a heat transfer medium, then pipe should be sealing to eliminate possible oxidation or other reactions between metal and the composition of air.If use helium, nitrogen or carbon dioxide, then pipe can open wide at the place, top under responseless situation between metal and the gas.For other gas, potential reacting to each other must be considered.

For the operation that is combined with the liquid metal heat reservoir embodiment of thermal source and turbine of the present invention is described, Fig. 3 a, Fig. 3 b and Fig. 3 c illustrate the embodiment of total system.Fig. 3 a illustrates hot storage system 111 and does not connect or be in the system unit under " pure solar energy " pattern.Air gets in the turbocompressor 112 and before arriving at thermal source 113 and is compressed.This thermal source possibly be that the high temperature solar receiver of heated air perhaps is non-solar energy high temperature thermal source through direct or indirect absorption sunlight.In addition, thermal source 113 can be the high temperature solar receiver of band window, and it uses granule to absorb focusing sunlight 116 and heating carries short grained gas.The example of this receiver is discussed in following document: " Solar Test Results of an Advanced Direct Absorption High Temperature Gas Receiver (SPHER) " by A.J.Hunt and C.T.Brown, Proc.Of the 1983 Solar World Congress, International Solar Energy Society; Perth, Australia, Aug.15-19; 1983, LBL-16947 (" the solar energy test result of advanced direct absorption high-temperature gas receiver (SPHER) ", A.J.Hunt and C.T.Brown; Nineteen eighty-three world's solar energy conference collection of thesis; International Solar Energy Society, Perth, Australia;-19 days Augusts 15 of nineteen eighty-three, LBL-16947); And " Heat transfer in a directly irradiated solar receiver/reactor for solid-gas reactons ", by H.H.Klein, J.Karni; R.Ben-Zvi and R.Bertocchi; Solar Energy 81 (2007) 1227-1239 (" in direct irradiation formula solar receiver/reactor, being used for the heat transmission of solids-gases reaction ", H.H.Klein, J.Karni; R.Ben-Zvi and R.Bertocchi; Solar energy 81 (2007), 1227 pages to 1239 pages), these documents are incorporated this paper into through the mode of reference.Gas gets into after being heated to high temperature in the expansion turbine 114, and this gas provided power with operation compressor and rotating generator 115 before being discharged or obtaining.Fig. 3 b illustrates the layout that is used to make the heat absorption of heat accumulation portion, wherein all gas process storage system before passing expansion turbine.Fig. 3 c illustrates the system operation that is under " mixing " pattern, wherein walks abreast through heat accumulation portion and turbo machine gas-selectively, regulates through control valve 117 and 118.Valve 117 can directly be diverted to gas solar receiver or thermal source 113 (being used for the embodiment's of Fig. 3 a operation) or directly be diverted to heat reservoir 111 (being used for the embodiment's of Fig. 3 b operation).Valve 118 can be with gas turns to hot storage system 111 or to expansion turbine 114.Valve 117 and 118 all places can be allowed the directly energy operation through being provided by receiver or thermal source 113 of expansion turbine 114, and the perhaps energy operation through being provided by hot storage system 111 alternatively is perhaps by the two energy that provides operation.

Claims

1. one kind is used for from stored and obtained the system of heat energy by the gas of high temperature source heating, and said system comprises:

The cavity of receiving heat-exchanger element; Wherein, Be heated gas and pass the said cavity that holds said heat exchanger element; Said heat exchanger element and non-alkali metal or metal alloy thermal communication, said non-alkali metal or metal alloy are melting under the specified temp between 600 ℃ and 1400 ℃ with storage heat energy; And

The identical or different cavity that holds identical or different heat exchanger element; Wherein, Gas to be heated passes the said identical or different cavity that holds said identical or different heat exchanger element; Said identical or different heat exchanger element and same metal or metal alloy thermal communication, said same metal or metal alloy solidify at least in part, thereby emit the heat energy of being stored.

2. the system of claim 1 comprises the metal alloy composition that is used for the latent heat heat reservoir, and said metal alloy composition is fusing under specified temp through the percentage composition that changes every kind of composition.

3. the system described in claim 1, wherein, said heat exchanger element is a pipe, said pipe is formed by high-temperature ceramic materials.

4. the system described in claim 1, wherein, said heat exchanger element is a pipe, and said pipe forms by having the high-temperature metal alloys that operating temperature is significantly higher than the melting point of said metal or metal alloy.

5. the system described in claim 1, wherein, said heat exchanger element is a pipe, and said pipe is formed by graphite.

6. the system described in claim 1, wherein, said tube for heat exchanger is a pipe, and said pipe forms by the graphite that is coated in metal or the pottery, when using oxidizing gas as heat transfer medium, to prevent oxidation.

7. the system described in claim 1, wherein, said heat exchanger element is a pipe, and said pipe is solid graphite or the solid metal with coating.

8. the system described in claim 1; Wherein, Said heat exchanger element is a pipe, and said pipe be hollow and hold element or the compound of fusing point that boiling temperature is higher than said metal or metal alloy so that heat is sent in the said metal or metal alloy from said solar energy source.

9. the system described in claim 1; Wherein, Said heat exchanger element is a pipe, and said pipe be hollow and hold element or the compound of fusing point that boiling temperature is lower than said metal or metal alloy so that heat is sent to gas stream to be heated from said metal or metal alloy.

10. the system described in claim 1, wherein, said heat exchanger element is a pipe, and said pipe is arranged so that the maximizes heat transfer between said pipe and said heat transfer gas.

11. the system described in claim 1, wherein, said heat exchanger element is a pipe, and said pipe is a kind of in hollow stem or the solid hopkinson bar, has radial fins or axial fin to improve heat transmission.

12. the system described in claim 1, wherein, said heat exchanger element is a pipe, and the Cross section Design of said pipe is to make maximizes heat transfer between said pipe and said heat transfer gas.

13. the system described in claim 1 uses air, carbon dioxide, argon gas, helium or nitrogen as said heat transfer gas.

14. the system described in claim 7, wherein, said high temperature source comprises that solar receiver makes said metal or metal alloy fusing with heated air so that heat to be provided.

15. the system described in claim 1 comprises combustion gas turbine, said system uses the heat of being stored to come the operating gas turbine machine so that machine power to be provided.

16. the system described in claim 14; Wherein, Said high temperature source comprises the high temperature solar receiver of being with window; The high temperature solar receiver of said band window uses granule to absorb focusing sunlight and heating carries said short grained gas, and said gas comprises at least a in air, carbon dioxide, helium or the nitrogen.

17. the system described in claim 1 comprises the metal alloy that is formed by two kinds or more kinds of element, the melting point of said metal alloy is by the selection of the percentage composition of said two kinds or more kinds of elements and confirm.

18. the system described in claim 1, wherein, said metal alloy comprises aluminium and silicon, has from 600 ℃ to 1400 ℃ melting point.

19. one kind is used for from by the gas of high temperature source heating with to said atmosphere storage and the method for obtaining heat energy, said method comprises the steps:

Make and be heated the cavity that gas passes the receiving heat-exchanger element; Said heat exchanger element and non-alkali metal or metal alloy thermal communication, said non-alkali metal or metal alloy melt the heat energy that is the latent heat of fusion form of said metal or metal alloy with storage under the specified temp between 600 ℃ and 1400 ℃; And

Gas to be heated is passed hold the identical or different cavity of identical or different heat exchanger element; Said identical or different heat exchanger element and same metal or metal alloy thermal communication; The partial coagulation at least of said same metal or metal alloy, thus heat energy emitted with the latent heat of fusion stored in form.

20. method as claimed in claim 19 comprises and chooses the metal alloy composition that is used for the latent heat heat reservoir, makes said metal alloy melt under specified temp through the percentage composition of each composition of the said metal alloy of change.

21. one kind is used for from stored and obtained the system of heat energy by the gas of high temperature source heating, said system comprises:

The cavity of receiving heat-exchanger element; And

Be contained in non-alkali metal or metal alloy in the said heat exchanger element, said non-alkali metal or metal alloy are suitable for storing the heat from being heated gas.

22. the system of claim 1, wherein, said metal or metal alloy is in fusing under the specified temp between about 600 ℃ and 1400 ℃.

23. one kind is used for from stored and obtained the system of heat energy by the gas of high temperature source heating, said system comprises:

First passage with first heat exchanger element;

Second channel with second heat exchanger element;

The cavity that holds non-alkali metal or metal alloy, said non-alkali metal or metal alloy are suitable for storing the heat from being heated gas; And

Said first and second heat exchanger elements partly extend in the said cavity.

24. the system of claim 1, wherein, said metal or metal alloy is in fusing under the specified temp between about 600 ℃ and 1400 ℃.

25. one kind is used for from atmosphere storage and the method for obtaining heat energy by the high temperature source heating, said method comprises the steps:

Make to be heated the cavity that gas passes the receiving heat-exchanger element, said heat exchanger element and non-alkali metal or metal alloy thermal communication, said non-alkali metal or metal alloy fusing are with storage heat energy; And

Gas to be heated is passed hold the identical or different cavity of identical or different heat exchanger element; Said identical or different heat exchanger element and same metal or metal alloy thermal communication; The partial coagulation at least of said same metal or metal alloy, thus the heat energy of being stored emitted.

26. method as claimed in claim 25, comprise in the aforesaid right requirement each or all.

27. system as claimed in claim 21, comprise in the aforesaid right requirement each or all.

28. system as claimed in claim 23, comprise in the aforesaid right requirement each or all.