Abstract:
The present invention relates to a zero-emission renewable heating system utilizing a thermal energy capacitor system using solar power as its source of heat, and more particularly, to a solar thermal capacitor system using an solar concentrators and a molten salt cell with thermal storage capability.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a zero-emission renewable heating system utilizing a thermal energy capacitor system using solar power as its source of heat, and more particularly, to a solar thermal capacitor system using an solar concentrators and a molten salt cell with thermal storage capability. 
       BACKGROUND OF THE INVENTION 
       [0002]    The desire to decrease and ultimately eliminate dependence on limited energy resources has stimulated research into clean and renewable ways to conserve resources and utilize renewable energy sources. Solar power has become a viable option because it is a clean form of energy production and there is a potentially limitless supply of solar radiation. To that end, it is estimated the solar energy flux from the sun is approximately 2.7 megawatt-hours per square meter per year in certain advantageous areas of the world. With this tremendous amount of free and clean energy available, and the desire to reduce dependence on limited resources, solar power production is now, more than ever, being reviewed as an important means to help meet the energy consumption demands in various parts of the world. 
         [0003]    Molten salt is used in solar power tower systems because it is liquid at atmosphere pressure, it provides an efficient, low-cost medium in which to store thermal energy, its operating temperatures are compatible with todays high-pressure and high-temperature steam turbines, and it is non-flammable and nontoxic. In addition, molten salt is used in the chemical and metals industries as a heat-transport fluid, so experience with molten-salt systems exists for non-solar applications. 
         [0004]    Molten salt is also an efficient heat capacitor, with low heat dissipation. It retains thermal energy very effectively over time and operates at very high temperatures. It is relatively inexpensive and plentiful, and generally non-toxic. Thermal storage is widely regarded as the future for the renewable energy campaign because, unlike many intermittent renewable resources such as wind energy, it offers a “zero-emissions” technology. 
         [0005]    Several molten salt heat transfer fluids have been used for solar thermal systems. The binary Solar Salt mixture was used at the 10 MWe Solar Two central receiver project in Barstow, Calif. It will also be used in the indirect TES system for the Andasol plant in Spain. Among the candidate mixtures, it has the highest thermal stability and the lowest cost, but also the highest melting point. Hitec HTS® has been used for decades in the heat treating industry. This salt is thermally stable at temperatures up to 454° C., and may be used up to 538° C. for short periods, but a nitrogen cover gas is required to prevent the slow conversion of the nitrite component to nitrate. The currently available molten salt formulations do not provide an optimum combination of properties, freezing point, and cost that is needed for a replacement heat transfer fluid in parabolic trough solar fields. Therefore, the work summarized in this report sought to develop an heat transfer fluid that will better meet the needs of parabolic trough plants. 
         [0006]    In many areas of the world, thermal energy for heating and cooking use coal or wood or such other resource. These resources generally are not renewable and emit significant waste. Accordingly, a need exists for a thermal energy generation system capable of efficient energy collection, with high temperature capability, and with the ability to store collected energy in areas where resources are extremely limited. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention is directed to a solar power thermal energy capacitor capable of storing heat energy wherein sun light is converted to thermal energy. The solar power system includes a solar concentrator system, which concentrates the sunlight onto thermal capacitor. The concentrated sunlight heats a surface of the thermal capacitor. 
         [0008]    Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
           [0010]      FIG. 1  is a schematic of a solar thermal capacitor system according to a preferred embodiment of the present invention; 
           [0011]      FIG. 2  is a schematic of an alternate solar thermal capacitor system according to a preferred embodiment of the present invention; 
           [0012]      FIG. 3  is a drawing of a linear Fresnel concentrator and a linear thermal capacitor; 
           [0013]      FIG. 4  depicts variations of mirror concentrators as the solar concentrator component; 
           [0014]      FIG. 5  a schematic of an alternate solar thermal capacitor system having multiple solar concentrators according to a preferred embodiment of the present invention; 
           [0015]      FIG. 6  depicts variations of thermal capacitor cells; 
           [0016]      FIG. 7  is a sectional perspective of a solar thermal capacitor system; 
           [0017]      FIG. 8  illustrates a stand-alone system utilizing a large Fresnel lens to heat thermal capacitor according to the teachings of the present invention; 
           [0018]      FIG. 9  is a schematic of a solar thermal capacitor system having multiple collection systems according to the teachings of the present invention; 
           [0019]      FIG. 10  is a schematic of a solar thermal capacitor system illustrating the tracking of the sun by the system according to the teachings of the present invention; 
           [0020]      FIG. 11  is a schematic of an alternate solar thermal capacitor system having multiple collection systems according to the teachings of the present invention; 
           [0021]      FIG. 12  is a schematic of a complete solar thermal capacitor system capable of tracking the sun according to the teachings of the present invention; 
           [0022]      FIG. 13  illustrates the use of a solar thermal capacitor system during the day and night in a house for cooking and heating according to the teachings of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0023]    The following description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
         [0024]    With reference to  FIG. 1 , a solar thermal capacitor system  10  in accordance with a preferred embodiment of the present invention is shown. The solar thermal capacitor system  10  includes a solar collection system  12  and a thermal capacitor  16 . The solar collection system  12  gathers sunlight and concentrates the sunlight to a thermal capacitor  16 . The thermal capacitor  16  uses molten salt  14  to store the thermal energy from the solar collection system  12 . 
         [0025]    The solar collection system  12  has a solar concentrator  18 . The solar concentrator  18  gathers sunlight and concentrates the sunlight. The solar concentrator  18  includes a lens  22  or a mirror. In one preferred form, the lens  22  is a Fresnel lens ( FIG. 1 ) or a magnifying lens ( FIG. 2 ). The sunlight strikes the lens  22  and is focused onto the thermal capacitor  16  below the lens  22 . The lens  22  is coupled to a support structure  26  that supports the lens  22  and operably coupled to a base. The thermal capacitor  16  can be independent of support structure  26  ( FIG. 1 ) or dependent from the support structure  26  ( FIG. 2 ). 
         [0026]    The concentrating component (interchangeably referred to also as lens or mirror)  18 , which can help focus the spatially decomposed solar spectrum onto the thermal capacitor  16 , can be provided in any number of useful configurations. Preferred designs utilize optical lens to concentrate diffracted light. 
         [0027]    The optical component used in the solar concentrators typically provides a 2-10000 fold concentration, more preferably 5-1000, more preferably 10-500-fold concentration of the sun irradiance, most preferably greater than a 10-fold concentration. The concentrator can take different forms such as, but not limited to, rectangular, polygonal or circular shapes (including arcs, cylinders, semi-cylinders, planes, etc), and can be made of any suitable materials. Concentrators can include, e.g., a convex lens (both biconvex and plano-convex), positive or negative meniscus lens, a gradient refractive index lens, a Fresnel lens, standard magnifying lens, or other type of light concentrating lens, and/or the like (see  FIG. 2 ). The choice of lens can be influenced by design requirements such as aspect ratio, weight, cost and the reliability desired in the concentrator structure, as further described below. 
         [0028]    Concentrator  18  is mounted on the very top of the assembly and concentrates the light energy from the sun through top aperture. The concentration of the light energy need not be at a focal point when entering the aperture. The lens may be a standard magnifying lens ( FIG. 2 ), a Fresnel type lens ( FIG. 1 ) or other type of light concentrating lens and may be round, elliptical, semi-elliptical ( FIG. 3 ), rectangular (or rectangular with rounded edges), triangular, or irregular in general shape when looking at the direction of the light path (from the side). The lens is designed to fit the top of the assembly as well as focus as much light on the thermal capacitor  16  of the device. The lens can take the general structure of the housing or be embedded within the housing ( FIG. 2 ). 
         [0029]    The shape of the concentrator can be modified to adjust the concentration and direction of the light energy to optimize its use so as to increase efficiency and maximize heat generation. In one embodiment, the lens  22  in  FIG. 3  is shaped to concentrate the sunlight linearly creating a focal line at the top of the thermal capacitor  16  or off-focus below the thermal capacitor. More preferably, the concentrator will concentrate the light at the top of the thermal capacitor  16  to generate maximum heat. 
         [0030]    With reference to  FIG. 4 , the focal length of a lens in air can be calculated from the lensmaker&#39;s equation: 
         [0000]    
       
         
           
             
               
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         [0031]    where 
         [0032]    f is the focal length of the lens, 
         [0033]    n is the refractive index of the lens material, 
         [0034]    R1 is the radius of curvature of the lens surface closest to the light source, 
         [0035]    R2 is the radius of curvature of the lens surface farthest from the light source, and 
         [0036]    d is the thickness of the lens (the distance along the lens axis between the two surface vertices). 
         [0037]    To increase the incident light&#39;s intensity you have to change material (higher refractive index) or decrease the focal length increasing the lens curvature (higher aberrations) or increase the optical quality. 
         [0038]    By example and without limitation, the concentrator is formed of glass, acrylic, silicone, plastic, polycarbonate, or fluoropolymers (e.g., Ethylene Tetrafluoroethylene (ETFE), or another transparent material to have a focal length structured for focusing or concentrating the light energy from the sun through top aperture. Preferably, solar concentrator is formed of material with thought to such attributes as resistance to warping or corrosion, breaking, cracking, scratching, shattering, melting, extreme heat, oxidation and discoloration; little light absorption or loss; heat absorption, low cost, ease of manufacturing, strength, weight, availability, toxicity, magnification, regional availability of resources and manufacturing capabilities, combinations thereof, and the like. For example, ETFE film is utilized in a one embodiment of the present invention as it is 1% the weight, transmits more light and costs 24% to 70% less to install compared to glass. Commercially deployed brand names of ETFE include Tefzel by DuPont, Fluon by Asahi Glass Company, Neoflon ETFE by Daikin, and Texlon by Vector Foiltec. 
         [0039]    In other embodiments of concentrator components, concentrators are assembled from cast components, such as cast acrylic or other polymer (e.g., acrylate, methacrylate, polyethylene terephthalate (PET), polycarbonate) or a combination of cast components and extruded components or from optical components manufactured by various other manufacturing processes. Exemplary cast acrylic components include HESA-GLAS from Notz Plastics AG and available from G-S Plastic Optics located 23 Emmett Street in Rochester, N.Y. 14605. In an alternate embodiment, solar concentrators are manufactured from extrudable material such as various plastics e.g. Fluoroplastic, Fluoropolymer or Fluorocarbon. Exemplary extruded plastics include extruded acrylics and extruded polycarbonates available from Bay Plastics Ltd (United Kingdom). Lenses can be created using known techniques, including traditional polishing or computer-controlled milling equipment (CNC) that can turn out large complex pieces from single pieces of glass. Exemplary lens manufacturers include Kenteh Optical Co., Ltd. (Taiwan) and E-Tay Industrial Co., Ltd. (Taiwan), WuXi Bohai Optical Apparatus Electronic Co., Ltd. (China), Wenzhou Mingfa Optics Plastics Co., Ltd. (China), CDGM Glass Co., Ltd. (China), Ikeda Lens Industrial Co., Ltd (Japan), etc. 
         [0040]    Other choices of concentrators can include mirrors that reflect sunlight unto a single point or points (See  FIG. 4 ), such as with a) linear parabolic mirrors; b) compound linear fresnel mirrors; c) compound parabolic mirror(s); d) mirror array; e) compound hyperbolic mirrors; f) compound elliptic mirrors; and the like. These contractors can have a second concentration stage to further improve the quality or magnitude of concentration. 
         [0041]    As shown in  FIG. 5 , multiple lenses  22  and  24  can be employed in series to refract the light through each layer of lens. Each layer refracts the light  26  and reduces the distance between the 1st lens  22  and the thermal capacitor  16 . 
         [0042]    The sunlight is concentrated from the solar concentrator system  18  to the thermal capacitor  16  as shown in  FIG. 2 . The concentrated sunlight  14  heats the thermal capacitor  16  directly or through an absorber  30 . As shown in  FIG. 6 , the thermal capacitor can be various shapes, but is preferably in a shape that is portable and modular. Such shapes include cylindrical ( FIGS. 6A and 6B ), spherical, a block ( FIG. 6C ), cube, disc ( FIG. 6D ), rectangular ( FIG. 6E ), and other such shapes that lend the thermal capacitor to be transferred between different applications. For cost purposes, the cell can be a can and shaped accordingly. 
         [0043]    In a preferred embodiment, solar collection system  12  can concentrate sunlight unto the entire thermal capacitor  16  or a portion thereof. As shown in  FIGS. 1 and 2 , the upper portion of the thermal capacitor is an absorptive material  30 . The absorptive material  30  absorbs the solar energy and aids in the distribution of the resulting thermal energy to the molten salt  14 . The absorptive material  30  may include, for example, metal, graphitic absorbers or heat absorbers, including IR or UV absorbers. The absorber  30  can be as simple as coloring the top a heat absorbing color (e.g., black or other dark color) to a heat transmission tube  32  that transmits the heat throughout the thermal capacitor  16 . Heat tubes  32  can be used to receive the thermal energy from the absorption of concentrated sunlight and transfer the energy into the molten salt  14 . 
         [0044]    Infrared absorbing materials and coatings are well known in the art (see, e.g., U.S. Pat. App. No. 20090029057 and WIPO Patent Application WO/2008/071770). For example, a conductive silver coating which, when during the thermal fusing (firing) of the coating to a metal, glass, silicon, polymer, ceramic or ceramic glass enamel substrate, provides infrared absorption properties over an extended temperature range. Other materials include nanoparticle coatings. Depending on the infrared absorption resonance wavelength (i.e. the wavelength at which the nanoparticles primarily absorb) and the width of the absorbance range (i.e. the wavelength range over which the nanoparticles cause absorption), one can divide nanoparticles in different groups. A first group of nanoparticles absorbs infrared energy in a broad band in the wavelength range above 1000 nm. Examples comprise indium oxide, tin oxide, antimony oxide, zinc oxide, aluminum zinc oxide, tungsten oxide, indium tin oxide (ITO) nanoparticles, antimony tin oxide (ATO), antimony indium oxide or combinations thereof. A second group of nanoparticles absorbs infrared in the near infrared. The nanoparticles of the second group absorb infrared in the range 780-1000 nm. Examples of nanoparticles of the second group comprise hexaboride nanoparticles, tungsten oxide nanoparticles or composite tungsten oxide particles. Alternatively, a metal or other conductive material can be used to absorb heat generated by infrared. IR can cause substantial heat and absorbance of the IR can be dissipated through the housing by this method. Accordingly, infrared-absorbing materials can be placed on an outermost layer of the housing wall, preferably outside or exterior to the refractor component, more preferably on a metal, glass or other material layer. 
         [0045]    The thermal capacitor  16  can be further surrounded by an insulation layer  34  that reduces heat loss to the atmosphere and facilitate handling of the thermal capacitor  16  by a tool or by hand. The insulation layer  34  enables the thermal capacitor  16  to maintain temperature even if the sunlight has diminished or the thermal capacitor  16  is exposed to colder temperatures. Preferably, the insulation is rugged and resistant to rough environmental conditions. 
         [0046]    Referring to  FIG. 6 , the molten salt fuel  14  is stored in a thermal capacitor cell  40 , which acts to contain molten salt fuel  14 . Thermal capacitor cell  40  can be lined with an insulation layer  34 . Thermal capacitor cell  40  is capable of withstanding high temperatures, for example, temperatures of at least approximately 1200 degrees Fahrenheit (° F.), preferably at least approximately 1500° F., more preferably at least approximately 2000° F., and most preferably at least approximately 2500° F. Preferably, thermal capacitor cell  40  is resistant to corrosion and repetitive fluctuations in heat. Suitable materials for constructing thermal capacitor cell  40  include, but are not limited to: copper based alloys, nickel based alloys, iron based alloys, and cobalt based alloys, but also include such compounds such as aluminum, nickel, iron, titanium, stainless steel, or other metal or alloy. Examples of suitable commercially available nickel based alloys include: Hastelloy X, Hastelloy N, Hastelloy C, and Inconel 718, available from Special Metals Inc., Conroe, Tex. Examples of suitable commercially available iron based alloys include: A-286 and PM2000, available from Metallwerke Plansee, Austria. An example of a suitable commercially available cobalt based alloy includes: Haynes 25, available from Haynes International Inc., Windsor, Conn. Other compounds include ceramics or refractory materials, or other such compound. Preferably the material is common and cheap to manufacture or use. The thermal capacitor may have a barrier layer to reduce corrosion, for example a barrier layer comprising tungsten (W), platinum (Pt), titanium carbide (TiC), tantalum carbide (TaC), titanium oxide (for example, TiO2 or Ti4O7), copper phosphide (Cu2P3), nickel phosphide (Ni2P3), iron phosphide (FeP), and the like, or may comprise particles of such materials, preferably which is still capable of transferring heat. 
         [0047]    The products of high temperature corrosion can potentially be turned to the advantage of the engineer. The formation of oxides on stainless steels, for example, can provide a protective layer preventing further atmospheric attack, allowing for a material to be used for sustained periods at both room and high temperature in hostile conditions. Such high temperature corrosion products in the form of compacted oxide layer glazes have also been shown to prevent or reduce wear during high temperature sliding contact of metallic (or metallic and ceramic) surfaces. 
         [0048]    Plating, painting, and the application of enamel are the most common anti-corrosion treatments. They work by providing a barrier of corrosion-resistant material between the damaging environment and the (often cheaper, tougher, and/or easier-to-process) structural material. Aside from cosmetic and manufacturing issues, there are tradeoffs in mechanical flexibility versus resistance to abrasion and high temperature. Platings usually fail only in small sections, and if the plating is more noble than the substrate (for example, chromium on steel), a galvanic couple will cause any exposed area to corrode much more rapidly than an unplated surface would. For this reason, it is often wise to plate with a more active metal such as zinc or cadmium. 
         [0049]    Other methods for providing corrosion protection include anodizing, controlled permeability formwork, cathodid protection methods, and the like. 
         [0050]    Possible molten salts  14  that can be used include both pure inorganic and organic materials, and eutectic and non-eutectic mixtures. Such materials could have cationic or positively charged components such as alkali metals, alkaline earth metals, aluminum, gallium, indium, germanium, tin transition metals, lanthanide metals, phosphonium, ammonium, sulfinium, arsenium, and stibium ions including polyalkyl and polyaryl substituted species. The anionic or negatively charged components could include halides, oxides, sulfides, nitrates, carbonates, carboxylates, silicates, aluminates, sulfates, phosphates, arsenates, borates, alkoxides, and aryl and alkyl sulfonates. 
         [0051]    The molten salt medium  14  of solar thermal capacitor  16  is a molten salt capable of being heated to high temperatures. The molten salt used in the thermal capacitor is capable of being heated to high temperatures, for example, to a temperature of at least approximately 1200 degrees Fahrenheit (° F.), preferably at least approximately 1500° F., and more preferably at least approximately 1700° F., or above approximately 1800° F. Most preferred are salts that are not liquid at ambient temperature, but salts that are liquid (having a melting point) above ambient temperature, e.g., non-ionic liquids. Alternatively, molten salt used in the thermal capacitor are salts that have melting points above ambient temperature. Inspection of published phase diagrams revealed that ternary mixtures of NaNO3 and KNO3 with several alkali and alkaline earth nitrates have quite low melting points. The eutectic of LiNO3, NaNO3 and KNO3 melts at 120° C., while a mixture of Ca(NO3)2, NaNO3 and KNO3 melts at about 133° C. Several eutectic systems containing three constituents are liquids as low as 52° C. Other salts, are for example, low-melting point salts described in U.S. Pat. No. 7,588,694 (incorporated herein). 
         [0052]    The molten salt can be salts composed of alkaline earth fluorides and alkali metal fluorides, and combinations thereof. Suitable elements of the molten salt include: Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Cesium (Cs), Francium (Fr), Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Ba), Radium (Ra), chlorine (Cl), bromine, iodine, Cyanide, Hydroxides, Nitrates, and Fluorine (F). 
         [0053]    Common salt-forming cations include: 
       Ammonium NH4+ 
     Calcium Ca2+ 
     Iron Fe2+ and Fe3+ 
     Magnesium Mg2+ 
     Potassium K+ 
     Pyridinium C5H5NH+ 
       [0054]    Quaternary ammonium NR4+ 
       Sodium Na+ 
       [0055]    Common salt-forming anions (parent acids in parentheses where available) include: 
         [0000]    Acetate CH3COO− (acetic acid)
 
Carbonate CO32− (carbonic acid)
 
Chloride Cl− (hydrochloric acid)
 
Citrate HOC(COO—)(CH2COO—)2 (citric acid)
 
       Cyanide C≡N− (N/A) 
       [0056]    Nitrate NO3− (nitric acid)
 
Nitrite NO2− (nitrous acid)
 
Phosphate PO43− (phosphoric acid)
 
Sulfate SO42−(sulfuric acid)
 
         [0057]    Examples of suitable fluoride molten salts include, but are not limited to: FLiNaK, FLiBe, FLiNaBe, FLiKBe, and combinations thereof. The salt can further contain a metal such as scandium, yttrium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, technetium, rhenium and lanthanoid. 
         [0058]    In a preferred method, the present invention is directed to a molten salt bath including at least two types selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, and barium; at least one type selected from the group consisting of fluorine, chlorine, bromine, cyanide, and iodine; at least one element selected from the group consisting of scandium, yttrium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, technetium, rhenium and lanthanoid (hereinafter, this element may also be referred to as “heavy metal”); and an organic polymer including at least one type of a bond of carbon-oxygen-carbon and a bond of carbon-nitrogen-carbon. 
         [0059]    In one embodiment, molten salts preferred are salts that are readily available, cheap, and bountiful, for example rock or halite salts, or salts primarily composed of sodium chloride (generally, having a melting point greater than 801° C., or 1474° F.). 
         [0060]    In an alternative embodiment, the molten salt  14  is a 60/40 mixture of sodium and potassium nitrate, commonly called saltpeter. The salt melts at 430° F. and is kept liquid at 550° F. in an insulated thermal capacitor cell. However, the molten salt  42  could also be a salt carbonates (e.g., Na2CO3, sodium carbonate &amp; other carbonates of lithium, potassium, etc.). Alternative salts include combinations of nitrates (e.g., potassium (KNO3), Sodium (NANO3)) and nitrites (e.g., sodium (NaNO2), K—Na—Ca Nitrate mixtures, a Eutectic mixture (46:24:30) with a melting point of 160° C.; K—Na—Li Nitrate Mixture with a melting point as low as 120° C., HITEC, a combination of NaNO2, NaNO3, KNO3 (40:7:53) with a melting point of approximately 142° C.; or 45.5 wt % potassium nitrate (KNO3) and 54.5% sodium nitrite (NaNO2), and the like. 
         [0061]    The thermal capacitor cells  40  are surrounded by an insulation layer  34  or insulation barrier (e.g., structure) that reduces heat loss to the atmosphere. In particular, high wind speed contributes to heat loss, as the high winds produce convective losses, and a recessed structure is preferable. 
         [0062]    In a preferred embodiment, the molten salt  14  in the thermal capacitor  16  is capable of retaining heat for several hours if not several days. The salt liquefies upon reaching at or above it&#39;s melting point. If the concentrated sunlight is sufficient, the salt will liquefy to become molten salt, which does not require the solar concentrator to trace the traveling sun. A concentrator  12  affixed perpendicular to the thermal capacitor  16  may be sufficient to melt the salt  14 . It may not be necessary to heat the thermal capacitor  16  throughout the day. However, in certain environments or conditions, it may be preferred for the solar concentrator  12  to follow or track the sun and heat the thermal capacitor  16  throughout the day. As shown in  FIG. 7 , the solar concentrator system  18  includes a lens  22  to concentrate sunlight. The sunlight strikes the lens  22  and is focused onto the thermal capacitor  16  below the lens  22 . The lens  22  is coupled to a support structure  26  that supports the lens  22  and the thermal capacitor  16 . The support structure  26  is further coupled to a pivot assembly  28 . The pivot assembly  28  enables the lens  22  to be adjusted to track the sun as the sun travels across the sky and heat the thermal capacitor  16 . Specifically, the pivot assembly  28  provides two axes of rotation for the lens  22 , as known in the art. 
         [0063]    In an alternate embodiment, molten salt can be any crystalline molecule that can be liquefied using solar heat. Sugars, for example are readily available and can be made into molten sugars. Preferred are compounds that can crystallize upon cooling and liquefied upon heating. 
         [0064]    Support can be made of any material readily available and sturdy enough to support the other components, including wood, metals and the like. 
         [0065]    As shown in  FIG. 8 , the pivot assembly  28  is rotatably coupled to a base  50 . The base  50  is affixed to a ground surface and the thermal capacitors  16  remain stationary until they are needed. The lens  22  is adjusted to track the sun. The thermal capacitors  16  can be shaped to accommodate shifting focal points, e.g., multiple thermal capacitor cells, a rectangular cell or a base that can retain heat. A controller (not shown) can be coupled to the solar concentrator system  12  that controls the pivot assembly  28  so that it causes the lens  22  to track the sun across the sky. In a preferred embodiment, the base  50  holding the thermal capacitors  16  is built of heat absorbing material and/or painted to absorb heat. It may or may not be necessary to heat  50  the base to a temperature sufficient to melt the salt. In preferred embodiments, the base is built to provide further insulation to the capacitor cell, for example to encapsulate or embed  52  the thermal capacitor  16  (See  FIG. 9 ). The base can be painted black and be made of heat absorbing material such as concrete or metals. 
         [0066]    Alternatively, it may be preferred for the solar concentrator  12  to follow the sun  60  and heat the thermal capacitor  16  throughout the day. As shown in  FIG. 10 , the solar concentrator system  12  includes a lens to concentrate sunlight. The sunlight  60  strikes the lens  22  and is focused onto the thermal capacitor  16  below the lens  22 . The lens  22  is coupled to a support structure  26  that supports the lens  22  and the thermal capacitor  16 . The support structure  26  is further coupled to a pivot assembly  28 . The pivot assembly  28  enables the lens  22  to be adjusted to track the sun as the sun travels across the sky and heat the thermal capacitor. Specifically, the pivot assembly  28  provides two axes of rotation for the lens  22 , as known in the art. 
         [0067]    In yet an alternate embodiment, multiple solar concentrators can be utilized to heat multiple fuel cells  16  as shown in  FIG. 11 . The rows of solar concentrator systems are constructed with thermal capacitor.  FIG. 12  shows multiple lens  22  to concentrate light onto multiple thermal capacitors  16 . The lens  22  are coupled to a support structure  26  that support the lens  22  and the base  50 , which supports the thermal capacitor cells  16 . As represented in  FIG. 12 , the base  50  and the lens  22  sit in parallel planes. The base  50  is affixed to a pivot assembly. The pivot assembly  28  enables the lens  22  and the base to be adjusted to track the sun as the sun travels across the sky. Specifically, the pivot assembly  28  provides two axes of rotation for the lens  22 , as known in the art. To heat the specific thermal capacitor cell, the sun must lie approximately perpendicular to the lens and base. A thermal capacitor can contain molten salt  16   b  or salt that has been cooled, and likely crystallized  16   a . In an alternate system, the lens and the base are not in parallel planes. One skilled in the art will readily appreciate that the solar thermal capacitor system  10  can be scaled to accommodate a wide range of demands for solar power. 
         [0068]    As shown in  FIG. 1 , the solar concentrator system  18  includes a lens  22  or a mirror. In one preferred form, the lens  22  is a Fresnel lens. The sunlight  14  strikes the lens  22  and is focused onto the thermal capacitor XX below the lens  22 . The lens  22  is coupled to a support structure  26  that supports the lens  22 . The support structure  26  is further coupled to a pivot assembly  28 . The pivot assembly  28  is rotatably coupled to a base  50 . A controller  52  coupled to the solar concentrator system  12  controls the pivot assembly  28  so that it causes the lens  22  to track the sun across the sky. More specifically, the controller  52  drives a motor (not shown) associated with the pivot assembly  28  to pivot lens  22  as needed. 
         [0069]      FIG. 13  shows the solar thermal capacitor system in operation over a day and evening cycle. If sufficient solar thermal condition exists, the sunlight  14  strikes the lens  22  of the solar concentrator system  12 . The lens  22  concentrates the sunlight to the focus, which is essentially at the aperture. The sunlight passes through the aperture unto the absorber  30 . The thermal energy collected by the absorber  30  is absorbed and the resulting thermal energy is transferred into the salt  14  by the heat exchanger tubes  32 . During the day, the molten salt in the thermal capacitor cells are heated to a temperature from the concentrated sunlight above the melting point of the molten salt. Some of the thermal capacitor cells will contain salt in its liquid state and other capacitor cells will contain salt not melted, in its solid or crystal form. These must be heated above the salts melting point to be used in its application. Thermal capacitors can have a handle or slot to enable easy safe transport of the capacitors from one location to another. Thermal capacitors containing salt that has been cooled are returned back to solar thermal capacitor system to recycle into heating process. This process will repeat as long as a solar power generation condition exists. 
         [0070]    As shown in  FIG. 13 , the thermal capacitor  16  are used as heating fuel cells to use in stoves  70  to cook food or to warm houses  80 . In a preferred embodiment, devices are contemplated that can conduct and/or transmit the heat for its intended use, e.g., cooking or heating. A stove, for example, can be used for both cooking and heating. Thermal capacitor cells with molten salt replace thermal capacitor cells with salt in its solid form. Utilizing invention thermal capacitor cells provide a renewable fuel cell that does not emit lethal gas. An insulator can be placed on the outside of thermal capacitor cell to avoid burning. Alternatively, or in parallel, thermal capacitor cells can be moved by tools that are developed specifically for the fuel cell or as simple as a stick. 
         [0071]    In an alternate embodiment (not shown), solar thermal capacitor system can be tied into a heating system for houses. Thermal capacitors can be placed in long tubes under or in the structure of a house (permanently or by replacement) and heated with a solar concentration system. 
         [0072]    In an preferred embodiment of the present invention, the molten salt thermal capacitors are also used as battery fuel cells. Accordingly, the invention further comprises an anode and cathode connection to enable charging. Molten salt batteries are a of class high temperature electric battery that use molten salts as an electrolyte. They offer both a higher energy density through the proper selection of reactant pairs as well as a higher power density by means of a high conductivity molten salt electrolyte. They are used in services where high energy density and high power density are required. These features make rechargeable molten salt batteries a promising technology for powering electric vehicles. High operating temperatures of 400° C. (752° F.) to 700° C. (1,292° F.) typically would bring problems of thermal management and safety, and place more stringent requirements on the rest of the battery components. In the present invention, when used in extreme environments or environments with limited resources, high operating temperatures are permissible. 
         [0073]    While there are many different types currently being researched, the usual characteristics is to employ a mixture of various salt carbonates (e.g., Na2CO3, sodium carbonate &amp; other carbonates of lithium, potassium, etc.) as the electrolyte of a battery called a fuel cell. High temperature rechargeable molten salt batteries have been known that use transition metal sulfide cathodes. LiAl alloy anode, and a molten lithium-salt electrolyte. Molten salt cells are a class of primary cell and secondary cell high temperature electric battery that use molten salts as an electrolyte. They offer both a higher energy density through the proper selection of reactant pairs as well as a higher power density by means of a high conductivity molten salt electrolyte. They are used in services where high energy density and high power density are required. 
         [0074]    Sodium is attractive because of its high reduction potential of −2.71 volts, its low weight, its non-toxic nature, its relative abundance and ready availability and its low cost. In order to construct practical batteries, the sodium must be used in liquid form. Since the melting point of sodium is 98° C. (208° F.) this means that sodium based batteries must operate at high temperatures, typically in excess of 270° C. (518° F.). [citation needed] 
         [0075]    Sodium-sulfur battery and lithium sulfur battery comprise two of the more advanced systems of the molten salt batteries. The NaS battery has reached a more advanced developmental stage than its lithium counterpart; it is more attractive since it employs cheap and abundant electrode materials. Thus the first commercial battery produced was the sodium-sulfur battery which used liquid sulfur for the positive electrode and a ceramic tube of beta-alumina solid electrolyte (BASE) for the electrolyte. 
         [0076]    The ZEBRA battery operates at 250° C. (482° F.) and utilizes molten sodium aluminum chloride (NaAlCl4), which has a melting point of 157° C. (315° F.), as the electrolyte. The negative electrode is molten sodium. The positive electrode is nickel in the discharged state and nickel chloride in the charged state. Because nickel and nickel chloride are nearly insoluble in neutral and basic melts, intimate contact is allowed, providing little resistance to charge transfer. Since both NaAlCl4 and Na are liquid at the operating temperature, a sodium-conducting β-alumina ceramic is used to separate the liquid sodium from the molten NaAlCl4. 
         [0077]    For comparison, LiFePO4 lithium iron phosphate batteries store 90-110 Wh/kg and the more common LiCoO2 lithium ion batteries store 150-200 Wh/kg. Nano Lithium-Titanate Batteries store energy and power of (116 Wh &amp; 72 Wh/kg) and (1,250 W &amp; 760 W/kg). 
         [0078]    The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.