Abstract: The thermal energy storage material comprises at least one hydrated compound (such as an inorganic salt) having a reversible transition to the anhydrous or a less hydrated form and a hydrogel, comprising a water-swollen cross-linked polymer formed by cross-linking a synthetic hydrophilic polymer by a covalent cross-linking mechanism, throughout which the compound is dispersed. The hydrogel is made by reacting a water-soluble or water-dispersible synthetic hydrophilic polymer, which is preferably linear and thermoplastic, with a cross-linking agent therefor in an aqueous medium containing the hydrated compound. The hydrophilic polymer, the aqueous medium and the hydrated compound are used in such amounts that the storage material contains a major proportion, by weight, of the hydrated compound and a minor proportion, by weight, of the cross-linked polymer.

Abstract: The disclosure concerns a collector for solar heating apparatus which is adapted for vertical mounting and utilizes air as the heat exchange medium. The collector comprises a glazed insulated box containing a group of energy transfer units, each of which is formed by a pair of similar open top metal foil pans having flat bottom walls which are in abutment and outwardly flaring conical side walls. The pans carry a black energy-absorbing coating and preferably their abutting walls contain registering air flow openings. The energy transfer units are stacked in interfitting relationship in rows and columns, with the axes of adjacent interfitted units in each row and in each column extending in mutually perpendicular directions. The collector may be combined with a fan unit adapted to fit a standard window, thereby providing a portable, economical, auxiliary heater for a room of a building.

Abstract: A reversible liquid solid phase change composition comprising hydrated Mg(NO.sub.3).sub.2 /MgCl.sub.2, and one of the group of MgO, Mg(OH).sub.2, and/or NaBO.sub.2, added to the composition in an effective amount to suppress super-cooling of the Mg(NO.sub.3).sub.2 /MgCl.sub.2 liquid phase.

Abstract: A reversible liquid solid phase change composition comprising hydrated Mg(NO.sub.3).sub.2 and one of the group of MgO, Mg(OH).sub.2, MgCO.sub.3, CaO, Ca(OH).sub.2, and/or CaCO.sub.3, added to the composition in an effective amount to suppress supercooling of the Mg(NO.sub.3).sub.2 liquid phase.

Abstract: A reversible liquid solid phase change composition comprising hydrated Mg(NO.sub.3).sub.2 and one of the group of MgSO.sub.4, CaSO.sub.4, CuSO.sub.4, NiSO.sub.4, CoSO.sub.4, and/or ZnSO.sub.4, added to the composition in an effective amount to suppress supercooling of the MgNO.sub.3 liquid phase.

Abstract: A heat storing fireplace including a fire-box surrounded by a heat storage medium which is either an enclosure containing a material having a high specific heat such as sand or gravel or a large number of heat conducting bags containing a high specific heat material. Exhaust gases are conveyed from the fire-box to an exhaust outlet by several conduits extending through the heat storage medium in a circuitous path in order to transfer heat from the exhaust gases to the heat storage medium. Heat is further distributed through the storage material by a heat conducting lattice fastened to the conduits and extending through the storage medium in a circuitous path. Combustion air enters the bottom of the fire box through a combustion air inlet jacket surrounding the exhaust outlet in order to simultaneously pre-warm the combustion air while thermally insulating the exhaust outlet from its support structure. A draft is created through the fire-box by an exhaust fan mounted in the exhaust outlet.

Abstract: A closed pressurized solar heating system in which a solar collector is automatically drained of heat transport fluid and which contains no mechanical moving parts other than a system circulating pump. Pipe lines connect the solar collector to top and bottom openings of a sump tank which is initially filled with the fluid, water, to a level intermediate between the top and bottom openings. The sump tank contains an internal pipe extending from the top opening of the tank down to below the operating level of the transport fluid, which is lower than the initial fill level because of the fluid required to fill the collector. Drain-back automatically commences upon de-energization of the system pump, whereupon air from the upper part of the sump tank enters a vent in the sump tank internal pipe, breaking the vacuum existing within the flow return path from the collector and initiating fluid return from the collector to the sump tank.

Abstract: A thermal storage structure and process for making the same comprising a base material of a substantially open cell structure, with the pores interconnected and open to the surface. The open cell structure may be a volcanic rock or alternatively may be a synthetically made structure such as foamed glass, foamed concrete or foamed metal. The open cell material is completely saturated with a latent heat storage component such as a salt-hydrate or eutectic salts. In the process of making the latent heat storage structure, the latent heat storage component is melted in a container and the open cell structure is placed therein, whereupon the melt is spontaneously imbibed by the structure, replacing the air in the open cell structure with the liquid latent heat storage component. The structure, after cooling, is packaged or encapsulated with a vapor impermeable material.

Abstract: Encapsulation of Na.sub.2 SO.sub.4 particles by Glauber's salt crystals formed by crystallization of Na.sub.2 SO.sub.4 from aqueous solution in systems comprising Na.sub.2 SO.sub.4, H.sub.2 O and Glauber's salt is decreased by including ethylene glycol monobutyl ether in the system.

Abstract: A solar energy heat storage and transfer system (30) for use in a solar heating system includes an arrangement of interconnected heat storage modules (10). A first air path is provided from the solar collector through an inlet manifold (52) to the interior of each of the heat storage modules (10) to transfer the heat through the air passageways through a plurality of heat storage tubes (12). The first air path is completed by the return of the air to the solar collector from the heat storage modules (10) through an exhaust air manifold (54). A second air path is provided by a housing (32) surrounding the arrangement of heat storage modules (10) and connected to the distribution network of the heating system. An air inlet (34) allows air from the interior of a building to enter the bottom of the housing (32) and flow around an exterior conductive sheet (20) around each heat storage module (10) and through the outlet (36) to the remainder of the air distribution network of the system.

Abstract: The collection, storage and transfer of solar heat by pneumatic means includes: a solar collection system; a heat storage system; and a means for selectively directing air through the solar collector, the heat storage, and the point of use. The solar collection system includes a first chamber of convex, curvilinear shape covered with a light-transmissive material, and positioned to receive sunlight. A series of second chambers is formed beneath the first chamber by light-transmissive material located above and below a series of inclined ducts through which air from the first chamber is directed. Each duct receives air from the upper portion of the preceding secondary chamber and redirects the air into the lower portion of the next succeeding secondary chamber. After passing through the entire series of secondary chambers, the heated air is directed into a third concave, curvilinear-shaped chamber located beneath the series of second chambers.

Abstract: A passive thermal energy storage cell includes a container formed of suitable material. The container is filled substantially with a supercoolable material such as ethylene carbonate or a phase change material for storage of solar energy or the like. The container includes mechanical passive nucleating elements such as sharp pointed asperities on the wall, cold fingers or pointed members secured within the tank in continuous activating engagement with the supercoolable material to prevent supercooling thereof. Exchange elements are coupled to the supercoolable material for introduction of heat from a solar collector and removal of heat to a load. The material may be heated by the solar energy to or above melting temperature to store heat.

Abstract: A stored heat cooking utensil is provided which consists of an outer container, a cooking vessel, a heat storage element, a lid for enclosing the outer container and cooking vessel, a handle for manipulating the cooking vessel and the heat storage element, and a container handle which serves as a carrying handle for the cooking utensil and a lid securing device. The outer container consists of an insulated container having a tapered interior metal lining with an upwardly directed projection in the bottom. Projecting ears are provided on opposite sides of the container for attachment of the container handle in the form of a rope. The heat storage element is a disk of soapstone having a metal band around its exterior perimeter having its side perpendicular to the stone's top and bottom. The cooking vessel is a metal container having tapered sides. It has a pair of slots in its walls. A projecting rib extends around the perimeter of the vessel bottom. The upper rim has a projecting rolled edge.

Abstract: The invention relates to the use of crystalline resins as storage material in latent heat accumulators. Crystalline synthetic resins replace the crystalline inorganic salt of the known latent heat reservoirs. Preferably epoxide resins, polyurethane resins and polyester resins, which contain very specific long-chain polyester molecule moieties, are used. The crystalline synthetic resins have one or more, preferably two, crystallite melt temperatures.

Abstract: A paraffin composition that is solid at 25.degree. C. and has an improved heat reservoir by virtue of being combined with inert solid material, wherein the paraffin composition contains from 25 to 55% by weight of at least two constituents comprising aluminium or one of its oxides or silicates, and magnesium or one of its oxides or silicates.

Abstract: Na.sub.2 HPO.sub.4.12H.sub.2 O is prevented from deteriorating as a heat storage medium after repeated cycles of heat storage and heat withdrawal resulting from precipitation of dehydrated forms of the salt by mixing thoroughly into the dodecahydrate material a small water content up to 5% of the mixture by weight, after which the material is heated above the melting point of the dodecahydrate and then cooled in a gas-tight container. Between 0.1 and 2% by weight of urea, and most preferably about 0.7% by weight thereof, may also be incorporated into the mixture, as by first dissolving the urea into the water to be added, in order to reduce the thermal expansion coefficient of the heat storage medium.

Abstract: A forced air furnace includes a conventional fuel fired, primary heat exchanger and a secondary heat exchanger associated with the stack. The secondary exchanger includes a phase change material having a transition temperature within the range of the stack temperature, and which is disposed in heat exchange relation with the flue gases flowing through the stack. The secondary exchanger also includes duct means for conveying the circulated air in heat exchange relation with the phase change material; and the flow path through the secondary exchanger is an alternative path controlled by a damper. When the primary exchanger is turned on, the phase change material in the secondary exchanger is charged from the flue gases of the primary exchanger. When the phase change material is in condition to release stored heat, a temperature responsive control shuts off the primary exchanger and diverts the circulated air through the secondary exchanger.

Abstract: Apparatus for utilizing solar heat for heating a building, comprising a collector, a storage unit and means for transporting heated air from the collector to the storage unit and hence to rooms in the building, the apparatus being installed in the building so that the heat storage unit adjoins at least some of the rooms to be heated and comprises conduits terminating in said rooms.

Abstract: Energy is stored by heating a salt to a temperature above its latent heat of fusion to convert the salt to a liquid state. Heat is retrieved by moving a heat transfer fluid consisting of liquid metal or metals immiscible with the salt, and having a density less than that of the salt, over the top surface of the liquid salt at such a velocity that the upper layer of the salt is emulsified with the heat transfer fluid to crystallize the salt in the upper layer. Heat is thereby exothermally surrendered to the heat transfer fluid and the crystallized salt gravitates from said top surface, thereby maintaining the top surface in a liquid state. It is preferred to move the heat transfer fluid over the top surface of the salt in either a vortex pattern, or an outward radial pattern.

Abstract: A solar rock fireplace, to be connected to a forced air heating system, includes an enclosed heating chamber, a firebox where wood or other combustible material may be burned, a flue extending from the firebox along the length of the heating chamber, and a plurality of solar rocks positioned interiorly of the heating chamber and exteriorly of the firebox and flue. When material is burned in the firebox, the solar rocks are heated. When the air is circulated by the forced air heating system, the air flowing through the heating chamber is heated by the solar rocks.

Abstract: A solar collector is formed by a stack of vehicular tires for absorbing solar radiant energy. A series of conduits intercepting the upper and lower sidewall of each tire at locations spaced about 180 degrees apart couple together the hollow interiors of the tires in an air path passing angularly through each tire in two paths of about 180 degrees in length and serially from tire to tire for heat exchange purposes. A thermal energy storage medium is provided in the center of the stack which medium may be porous and switchable dampers are provided to selectively set up either a recirculating air path through the tires and the medium to transfer heat from the tires to the medium or a recirculating air path between the medium and a living space to be heated.

Abstract: An apparatus for storing electrically generated heat includes a sealed container holding a bed of fusible heat storage medium, such as an alkali metal hydroxide composition, and having an expansion space above the bed of material to accommodate the medium in its liquid phase. A generally horizontal main electric heating unit is located in the bottom portion of the container for heating the fusible medium above its melting point. A first vertical electric heater is provided in the bed of material in thermal contact with the main heating unit and has its active heating portion extends upwardly from the main heating unit only to the height of the heat storage medium in solid phase. A second vertical electric heater is located in the container in thermal contact with the first vertical heater with the active heating portion of the second heater extending only from the height of the fusible medium in solid phase to the height of the medium in the expanded liquid phase.

Abstract: The concentration of the solute in solution in a saturated non-convecting solar pond is greatest at a lower hotter level decreases continuously toward a higher cooler level and is saturated at all levels, thus preventing solute diffusion. In the customary operation of such saturated non-convecting solar ponds, the heat generated by incident radiation is absorbed in a bottom or lower layer. Because of the continuously decreasing density of solute which is near saturation from the lower to the upper layers, there is little salt convection and the pool tends to be further stabilized. Further, by heating due to absorption of the radiation largely at the lower level, a temperature gradient is maintained in which the upper layers remain cool, evaporation and consequent loss of heat is inhibited and the efficiency of the solar pond is improved. It has been discovered that a brine consisting essentially of an appropriate mixture of sodium carbonate (Na.sub.2 CO.sub.3) and sodium bicarbonate (NaHCO.sub.

Abstract: An improved energy storage superheater assembly for storing heat energy rlting from solar or other types of energy. An enclosed housing includes a heat transfer means in the bottom or top which is heated by SO.sub.2 +O.sub.2 due to solar chemical reaction or any other suitable means. The heat transfer means heats wet steam in a superheater piping that passes through the heat transfer means to produce superheated steam. A plurality of vertical, potassium-containing steel wall heat pipes extends from the heat transfer means and distributes heat over the large area of the housing. Vertical containers which contain a salt are assembled among the vertical pipes and are heated by the heat radiated and convected from the vertical pipes in order to store heat in the salt-containers by "heat of fusion". During heat withdrawal, heat is radiated and convected from the salt-containers to the vertical steel pipes. Heat is carried to the heat transfer means by the steel pipes which in turn heats the superheater tubes.

Abstract: The invention relates to a process for air-conditioning a greenhouse or the like for the cultivation of plants, due to the solar energy which is picked up during the day, wherein isothermic containers are disposed inside the greenhouse, which contain a body of which the melting temperature is between 10.degree. and 20.degree. C., so that, during the day, when the temperature inside the greenhouse exceeds said melting temperature, said body melts, absorbing calories and cooling the atmosphere of the greenhouse and, during the night, when the temperature becomes lower than said melting temperature, said body solidifies, releasing the latent heat of solidification.

Abstract: Solar heated or cooled building in which attic functions as solar energy collector, ducts are provided to convey air between attic and thermal storage chamber, two blowers, each preceded by a power-operated damper, are provided in the duct work to provide several automated modes of operation.

Abstract: A heat storage article adapted for prevention of stratification of incongruently melting heat storage materials, such as eutectic salts, and adapted for use with congruently melting heat storage materials, such as paraffins. The article is comprised of a concrete stone composition, a certain portion of which is comprised of metallic heat transfer materials in order to increase heat transfer through the concrete structure. The concrete structure has an internal cavity which is filled with either the eutectic salt material or the paraffin material.

Abstract: A system for transmitting, storing and utilizing cold which includes the use of heat pipes for transmitting the winter cold to freeze the ground water storage, and two-phase flow pipes to effectively cool the warm air passing through the flow pipes in the air conditioning duct. The system provides for long-duration earth storage of the winter cold which can be effectively used during summer seasons for cooling homes, buildings and other structures.The two-phase flow pipes, characterized by having irreversible vapor flow, include a pump arrangement for transferring working fluid from the condenser section to the evaporator section of the flow pipes where phase-change is taken place by absorbing heat from the passing warm air.

Abstract: A heating system for a building having a conventional gas furnace which includes a combustion chamber for heating air passing from a cold-air return to a hot-air duct is disclosed. The gas furnace includes an exhaust shack for exhausting hot gases from the combustion chamber externally of the building. The heating system includes a heat pump comprising a housing having a condenser for heating air passing thereby from the cold-air return to the hot-air duct. The gas furnace and heat pump are served by a single blower. The heat pump also includes an evaporator located externally of the building for drawing heat from the atmosphere. A timer is included to turn the furnace on when the heat pump has operated for a predetermined time in response to a demand for heat from a dwelling thermostat.

Abstract: Process and apparatus for control of the climatic environment of an underground enclosure having at least one source tending to emit a quantity of extraneous heat and associated with premises presenting a potential need for heating. Utilization is made directly of the regulating characteristics of the ground at a depth taking account of thermal inertia in order to enable the ground to operate as a heat source or thermal absorbent. For this purpose, apparatus is provided which is arranged entirely under the level of the ground at a mean depth which should not exceed 10 m, at latitudes in France, but this depth is variable according to the particular geological nature of the terrain. To take advantage of the thermal buffer the temperature of which is generally about 12.degree. C. in the Parisian region, the apparatus includes a wall structure with some of the walls formed of a material with a high coefficient of thermal exchange.

Abstract: A thermal energy storage and utilization system including at least a pair of especially configured liquid containing tanks interconnected by a heat exchanger for transferring thermal energy therebetween so that one of the tanks becomes a cold storage tank and the other becomes a heat storage tank. Various types of thermal energy input and output devices are connected to the liquid containing tanks for selectively supplying and/or utilizing the thermal energy stored therein.

Abstract: Aqueous heat-storage compositions useful in space heating applications are disclosed which contain a phase-change material which absorbs and stores heat as it is heated above its phase-change temperature and releases stored heat as it is cooled below its phase-change temperature. These compositions include fumed silicon dioxide which acts as a stabilizing agent and provides dramatically prolonged heat-storage efficiency for these compositions as they undergo repetitive cycling through their phase-change temperature. Articles containing such compositions and methods of forming such compositions are additionally disclosed.

Abstract: A heat storage apparatus and method including a heat storage medium encapsulated within a container and heat exchange apparatus for exchanging thermal energy with the heat storage medium. The heat storage medium may include a salt having a relatively high latent heat of reaction at a relatively low temperature range. The dehydration reaction of sodium sulfate decahydrate appears to the most promising reaction for this application. Other suitable salts and salt mixtures for other temperature ranges may also be used. The apparatus includes, where necessary, techniques for stirring the heat storage medium to inhibit stratification of the salt during cycles of dissolution and recrystallization or fusion.

Abstract: Thermal energy storage apparatus has a heat-insulating casing containing a length of flexible material extending between a pair of driven mandrels so that the material can be wound on either mandrel selectively. Between the mandrels the unwound material is heated as it passes a window in the casing through which solar energy is focused, and the heated material is collected in closely coiled form on the receiving mandrel, where it has a low exposed surface area for its thermal mass, to store the heat received. The stored energy is extracted from the coiled material by winding it onto the other mandrel while a gas flow is passed over the unwound material.

Abstract: An off-peak, electric, central air heating system for buildings incorporating a heat storage material that is used to store heat generated electrically during off-peak electrical power periods and to deliver heat on demand. The heat storage material is an alkaline metal or alkaline earth metal salt such as Na.sub.2 SO.sub.4, NaCl, CaCl.sub.2 and KCl individually or in combination with one another. Generation of heat during the off-peak electrical power periods is automatically controlled by an electronic time clock and time delay circuitry, and by selective variable temperature control. The heating unit is constructed with a casing having an inner jacket and an outer jacket with an air space between the two jackets. The storage material is surrounded by the inner jacket and the air space provides insulation as well as an air passage between the two jackets.

Abstract: The present invention relates to a heating and cooling system for structures such as residential dwellings. More particularly, the heating and cooling system includes one or more conduits disposed approximately six (6) feet underground and having opposite end extremities communicatively connected to the structure so as to define a closed air circulation system through the structure and one or more conduits. A fan assembly including appropriate controls is provided to induce and circulate air through the structure and through the one or more conduits such that a system of air may be continuously circulated from the structure through the underground disposed conduits and back through the structure.

Abstract: An especially compact, highly efficient heat recovery device for use in the cool air return duct of a heating system may be easily installed in existing flue pipes and transfers the ordinarily wasted heat in the exhaust gases flowing through the flue pipe to the cool return air thereby preheating the latter and increasing the efficiency of the heating system. The device includes a three stage heat transfer structure housed within a heat conductive tubular member which cooperate to transfer heat away from the gases into the cool return air by means of conduction, convection and radiation processes. A first stage deflects a portion of the gases toward and into heat exchanging contact with the sidewalls of the tubular member and directs the remaining portion into a gas pervious heat storage trap which comprises the second stage.

Abstract: A flow director including a diverting box defining four openings and having four baffles mounted therein. A damper is rotatable within the diverting box to provide for flow in one position between the first and fourth openings and between the second and third openings. In a second position of the damper flow is permitted only between the second and third openings. The combination of the flow director and an air treating means provides for desired flow paths of the air for heating and/or cooling purposes.

Abstract: A heat storage article adapted for prevention of stratification of heat storage materials, such as eutectic salts contained within the container element. The article is comprised of a heavy thermally conductive container with an internal cavity. The internal cavity of the container is substantially completely filled with a combination of a non-biodegradable filler material such as glass fiber insulation and a eutectic salt.

Abstract: Vehicular tires are generally toroidal heat collection elements of a solar heating system. Liquid or gaseous fluid flow is circulated between the tires and a space to be heated for transferring the heat from the tires to the space. The tires are generally vertically stacked within a thermally insulated enclosure which includes a double glazed window located that solar rays impinge on and heat the tires. Heat storage media such as water, rock or pebble beds, or phase change material in an elongated coiled jacket may be provided within the tires. Downwardly inclined vanes either partially cut from the tire walls or attached to the tires or attached to separators between the tires, provide additional surface area to absorb the solar radiation and to also direct airflow radially inward into the center of the tires.

Abstract: A portion of a suspended ceiling in a room is in the form of an open grid of reflective louvers, those facing a window being curved. A flexible bag containing a mixture including Glaubers salt is supported by the grid and suitable reflecting devices are associated with the window to reflect solar heat to and through the grid where it is absorbed by the mixture in the bag.

Abstract: A thermal energy storage system and method for storing substantial quantities of heat for extended periods of time. The system includes a heat collecting liquid which is in a heat-exchange relationship with a source of heat or thermal energy, a housing containing a large volume of particulate material such as rocks for the storage of thermal energy, a heat transfer gas in a heat-exchange relationship with the rocks and means for causing the heat collecting liquid and the heat transfer gas to flow in counter-current, indirect heat-exchange relationship with one another, the means further includes provisions for reversing the direction of flow of the liquid and gas for the introduction and removal of heat from a portion of the body of rock.

Abstract: A heat storage device comprising a closed reservoir within which is positioned a flexible closed container of smaller volume. The flexible container encloses a liquefiable heat-accumulating material; and the reservoir is provided with a heat-transport medium outside of the flexible container. The heat-transport medium always remains in the liquid phase and, upon solidification and shrinkage of the heat-accumulating material, fills the spaces thus formed between the flexible container and the reservoir wall in order to maintain adequate transfer of heat.

Abstract: A solar heating system with one or more collector panels having an insulative, fiberglass top, black, heat-producing plates and an air manifold at each end. Cold air is transmitted through a manifold, across the plates and out the other manifold. The heated air is directed to a heat-storage compartment in which heat is stored in containers of wax.

Abstract: The specification discloses a novel energy saving forced-air furnace. In contrast to previous forced-air furnaces, which ran only on gas or oil and in which approximately half of the energy derived from the burning fuel was lost through the chimney, the furnace of the present invention can run on coal, wood, gas or oil and retains a substantial portion of the heat which normally would be lost by the utilization of special tubing units and refractory plates. My furnace saves the greatest amount of energy possible by providing a heat chamber having a special tubing unit therein from the surface area of which heat generated in a stove chamber is transferred to a heat chamber and simultaneously through which exhaust gases air conducted from the stove chamber mounted below the heat chamber to the exterior of the furnace. Refractory plates are placed in a serial arrangement within the furnace heat chamber with spaces provided between them.

Abstract: A choke control device for delaying closing of a choke valve regulated by a temperature responsive bimetal coil after an internal combustion engine is turned off by employing a heat sink which stores the latent heat of fusion or vaporization that is delivered to the heat sink after the choke is open and the engine is operating at normal temperatures and which releases the latent heat after the engine has been turned off and cools to heat the bimetal coil and delay closing movement of the choke valve.

Abstract: A fluid thermosiphon system including a heat collection channel in communication above and below an insulating member to a heat storage region in a closed loop, the storage region includes spaced apart panels of an entirely encapsulated phase change material between which the heated fluid flows. The panels are adjacent the rear wall of the unit through which they disperse retained heat to the space. A wall or tilted roof unit suitable for built-in construction is disclosed, as is an exterior ground supported add-on unit. A liquid thermosiphon system is disclosed as the preferred embodiment. A gaseous system, using air, is also disclosed.

Abstract: The invention relates to an electric storage heater assembly which includes a core and a resistance heater for the core. A low tariff period switch and a charging switch are in series with the resistance heater. A triggering unit, which includes an integrator in one embodiment, and an integrator and comparator in a second embodiment, operates the charging switch. A feed circuit for charging the integrator is responsive to the indoor temperature and the unregulated heat loss from the core. A scanning circuit which produces the opposite effect is responsive to the regulated heat loss from the core and the outdoor temperature. The scanning circuit can be connected to either the integrator in one embodiment or to the comparator in the other embodiment.

Abstract: A container is disclosed for storing a heat storage medium which changes ween solid and fluid states to store and release heat, characterized in that the container includes flexible walls which are displaced to vary the volume of the container in accordance with changes of the volume of the heat storage medium when in the solid state. The container includes at least one biasing device which normally biases the resilient walls toward an inwardly contracted condition for storing a first volume of the heat storage medium in the fluid state. During initial removal of heat from the medium, the medium changes from its fluid to its solid state, and upon further removal of heat from the solid medium, the density of the solid medium increases, thereby resulting in a decrease in the volume of the solid medium with the container remaining in its initial contracted condition.

Abstract: A heat storage tank suitable for solar house heating systems. The tank includes a rigidly supported bottom panel covered with a layer of stones of substantially uniform size which are bonded together thermally and mechanically at their points of contact with each other, but which have voids forming air passages remaining between them, bottom insulation below said bottom panel, a bottom air passage between the bottom insulation and the bottom panel, and at least one opening in the bottom panel whereby air can pass from said bottom air passage into said layer of stones.