74 results about "Seasonal thermal energy storage" patented technology

Methods and apparatus for extracting stored thermal energy using a combined internal and external melt cycle are disclosed. The present invention relates, in one aspect, to a heat exchange system which uses both an internal melt cycle and an external melt cycle to extract stored thermal energy. The heat exchange system includes a thermal energy storage medium and a heat exchanger which is in communication with the thermal energy storage medium. The heat exchanger is arranged to hold a heat exchange liquid and to facilitate the indirect transfer of heat between the heat exchange liquid and the thermal energy storage medium. The heat exchange system further includes a fluid supply which provides a fluid which directly contacts the thermal energy storage medium to transfer heat between the fluid and the thermal energy storage medium.

An active thermal energy storage system is disclosed which uses an energy storage material that is stable at atmospheric pressure and temperature and has a melting point higher than 32 degrees F. This energy storage material is held within a storage tank and used as an energy storage source, from which a heat transfer system (e.g., a heat pump) can draw to provide heating of residential or commercial buildings and associated hot water. The energy storage material may also accept waste heat from a conventional air conditioning loop, and may store such heat until needed. The system may be supplemented by a solar panel system that can be used to collect energy during daylight hours, storing the collected energy in the energy storage material. The stored energy may then be used during the evening hours to heat recirculation air for a building in which the system is installed.

An active thermal energy storage system is disclosed which uses an energy storage material that is stable at atmospheric pressure and temperature and has a melting point higher than 32 degrees F. This energy storage material is held within a storage tank and used as an energy storage source, from which a heat transfer system (e.g., a heat pump) can draw to provide heating of residential or commercial buildings and associated hot water. The energy storage material may also accept waste heat from a conventional air conditioning loop, and may store such heat until needed. The system may be supplemented by a solar panel system that can be used to collect energy during daylight hours, storing the collected energy in the energy storage material. The stored energy may then be used during the evening hours to heat recirculation air for a building in which the system is installed.

A variety of energy storage and retrieval systems are described. Generally “hot” and “cold thermal reservoirs are provided. The “hot” reservoir holds both liquid and saturated vapor phase working fluid. The “cold” reservoir holds working fluid at a lower temperature than the hot reservoir. A heat engine/heat pump unit: (a) extracts energy from vapor passing from the hot reservoir to the cold reservoir via expansion of the vapor in a manner that generates mechanical energy to facilitate retrieval of energy; and (b) compresses vapor passing from the cold reservoir to the hot reservoir to facilitate the storage of energy. In some embodiments, the heat engine/heat pump takes the form of a reversible positive displacement heat engine that can act as both an expander and a compressor. To facilitate the storage and retrieval of electrical energy, an electric motor/generator unit may be mechanically coupled to the heat engine/heat pump unit.

During operation of an adiabatic compressed air energy storage (ACAES) system (50), energy imbalances may arise between thermal energy storage (TES,60) in the (ACAES) system and the amount of thermal energy required to raise the temperature of a given volume of compressed air to a desired turbine entry temperature T i after the air has been discharged from compressed air storage (62) of the ACAES system (50). To at last partially redress such an energy imbalance it is proposed to selectively supply additional thermal energy to the given volume of compressed air after it has received thermal energy from the TES (60) and before it expands through the turbine (58). The additional thermal energy is supplied from a source external to the ACAES system, such as fuel burnt in a combustor (56). The amount of thermal energy added to the given volume of compressed air after it has received thermal energy from the TES is much smaller than the amount of useful work obtained from the given volume of compressed air by the turbine (58).

A compressed air energy storage (CAES) system encompassing direct heating. The compressed air energy storage system includes a compressor for compressing ambient air, an air storage reservoir, and a thermal energy storage system. The air storage reservoir is adapted to store compressed air from the compressor. The thermal energy storage system is adapted to supply heat to the compressed air energy storage system such that the compressed air is heated to increase work production of the compressed air. The thermal energy storage system is heated using off-peak electricity.

Thermal storage systems that preferably do not create substantially any additional back pressure or create minimal additional back pressure and their applications in combined cycle power plants are disclosed. In one embodiment of the method for efficient response to load variations in a combined cycle power plant, the method includes providing, through a thermal storage tank, a flow path for fluid exiting a gas turbine, placing in the flow path a storage medium comprising high thermal conductivity heat resistance media, preferably particles, the particles being in contact with each other and defining voids between the particles in order to facilitate flow of the fluid in a predetermined direction constituting a longitudinal direction, arrangement of the particles constituting a packed bed, dimensions of the particles and of the packed bed being selected such that a resultant back pressure to the gas turbine is at most a predetermined back pressure.

The invention discloses a heating system for performing seasonal solar energy storage with a ground-source heat pump. The heating system comprises a solar thermal collector (1), a thermal collection water tank (2), a ground temperature recording system (3), a plurality of underground buried pipe heat exchangers (4), a soil heat pump unit (5) and a heating user (6), wherein a signal input end of the ground temperature recording system (3) is connected with a signal output control line of a ground temperature measuring device buried underground; the underground buried pipe heat exchangers are buried underground and arranged in parallel connection; a pipeline water inlet of the heating user is communicated with a water supply outlet of the soil heat pump unit through a heating pipeline, and a pipeline water outlet of the heating user is communicated with a water supply and water return port of the soil heat pump unit through a water return pipeline. The heating system has the advantages of being simple in structure, reliable in control and economically feasible. Meanwhile, a large amount of solar energy heat is stored in the thermal storage process, and thus the soil temperature is raised and the system efficiency of the soil source heat pump is improved. The heating system for performing seasonal solar energy storage with the ground-source heat pump is economical and safe.

An electrothermal energy storage and discharge system is provided including a charging cycle and a discharging cycle. The charging cycle includes a refrigeration unit and a thermal unit, and the discharging cycle includes a power unit. The refrigeration unit is driven by an excess electric power and is configured to generate a cold energy storage having a solid carbon dioxide. The thermal unit is driven by a thermal energy and is configured to generate a hot energy storage and/or provide a hot source. The power unit operates between the cold energy storage and at least one of the hot energy storage and hot source so as to retrieve the energy by producing a high pressure carbon dioxide and a hot supercritical carbon dioxide, and generating an electric energy using the hot supercritical carbon dioxide.

A thermal energy storage system is described employing latent heat storage of a supercritical fluid instead of typical phase change materials. Two fundamental thermodynamic concepts are invoked. First, by using the latent heat of liquid/vapor phase change, high energy density storage is feasible. Second, by operating the thermal energy storage system at a higher pressure, the saturation temperature is increased to operate at molten salt temperatures and above. Beyond the two-phase regime, supercritical operation permits capturing and utilizing heat taking advantage of latent and sensible heat, both in the two-phase regime as well as in supercritical regime while at the same time, reducing the required volume by taking advantage of the high compressibilities.

A combined cycle power plant for frequent stops and startups comprises at least one gas turbine, a heat recovery steam generator, at least one steam turbine and a thermal energy storage and retrieval system utilizing latent heat of fusion. Phase change materials receive thermal charge from two sources: (a) renewable energy generation plants, when their production exceeds demand and (b) gas turbine exhaust heat. The thermal energy storage and retrieval system, discharges efficiently thermal energy for steam production, which keeps the at least one steam turbine preheated and ready for fast startups, thus increasing the plant's flexibility and efficiency.

A novel two stage latent thermal energy storage system provides at least supercritical steam.

The invention relates to a solar energy and geothermal energy complementation type wind energy heat pump system. The system comprises a wind power generation device, a solar thermal collector, a high-temperature water source heat pump unit, a thermal/cold storage water tank, a thermal storage buried tube stack and a cold storage buried tube stack, wherein the wind power generation device provides electricity for the high-temperature water source heat pump unit, and the heat pump unit is connected with the thermal storage buried tube stack, the cold storage buried tube stack, the thermal/cold storage water tank and the solar thermal collector through connecting pipes, switch valves and water pumps respectively to realize the heat supply mode that a ground source heat pump is connected with the solar thermal collector in parallel, the heat supply mode that the ground source heat pump is connected with the solar thermal collector in series, the mode that the ground source heat pump supplies heat independently and the cold storage buried tube stack conducts cold storage, and the mode that the ground source heat pump conducts refrigeration independently and the thermal storage buried tube stack conducts thermal storage respectively. The system solves the problem of wind curtailment during wind power generation, solar energy serves as the auxiliary heat source of the heat pump unit, the problem that heat absorption and heat extraction of soil are unbalanced is solved, cross-seasonal solar energy storage is achieved, and the energy efficiency ratio of the heat pump system is increased.

The invention provides a computer room air-conditioning system performing combined operation of phase change thermal energy storage, a natural cold source and an artificial cold source, and relates to a computer room air-conditioning system performing combined operation of phase change thermal energy storage, the natural cold source and the artificial cold source. The computer room air-conditioning system comprises a phase change thermal energy storage device (1), an outdoor air cooling device (2), an air-conditioning water chilling unit (3), an indoor fan coil (4), a circulating water pipe (5) and an intelligent expert control system (6). The expert control system controls the time-sharing mutual combined operation of the indoor fan coil, the natural cold source equipment, the artificial cold source equipment and the phase change thermal energy storage device according to a set temperature of a computer room and an indoor environmental temperature, so that the natural cold source can be utilized fully and effectively; time-shifting application of energy is realized through phase change thermal energy storage, and efficient energy storage is conducted by utilizing valley-price electricity at night; and artificial refrigeration equipment is enabled to operate efficiently. The computer room air-conditioning system provided by the invention has high efficiency, saves energy, protects the environment and is economical in operation.

Disclosed is a thermal energy storage system for storing collected solar thermal energy. The system comprises a solar thermal energy collection facility in the form of a field of parabolic troughs, which is in thermal communication with a molten salt circuit. The molten salt circuit is in fluid communication with a molten salt storage facility comprising at least three storage tanks that are each in fluid communication with the molten salt circuit. The multiple tanks set-up allows using cheaper materials, and a more efficient storage of thermal energy.

A thermal energy storage system includes fluid conduits disposed in a loose solid material. The loose solid material may be disposed inside a waterproof barrier, and the fluid conduits may be configured to define a plurality of zones having different temperatures in operation. The system may include a solar collector or other source of heated oil or other fluid that is routed to the thermal energy storage unit and/or an energy-consuming facility.

The invention provides a thermal energy storage and heat exchange unit, comprising a solid state thermal storage material, a heat transfer fluid and means for energy input and output, distinctive in that: the storage comprises at least one heat transfer container, solid state thermal storage material is arranged around the heat transfer container, and the heat transfer container contains the heat transfer fluid and the means for energy input and output, so that all heat transferring convection and conduction by the heat transfer fluid takes place within the respective heat transfer container. Method of building the thermal energy storage, plant comprising the storage, method using the plant and use of the storage or plant.

The invention relates to a system for the storage and recovery of thermal energy, using, as its medium, at least one phase change material (solid-liquid) and a sensible heat solid material for storing/recovering the heat obtained from an external source in the form of phase change latent heat and sensible heat. The aforementioned materials are duly housed inside a single tank containing at least two zones which are differentiated by the range of temperatures to which they are subjected, each zone containing a different material. The most common configuration consists of three different zones located inside the tank, namely: a hot zone in the upper part of the tank, enclosing an encapsulated phase change material characterised by a high melting temperature; a cold zone housed in the lower part of the tank, containing a phase change material with a low melting temperature; and a middle zone containing a sensible heat solid material.

The invention relates to a universal system for producing cost effective energy particularly for cooling purposes. In one embodiment, wind turbines are used to generate electricity and compressed air energy, wherein the compressed air energy is used to co-generate electricity and chilled air. The chilled air is then used to chill water in either a mixing chamber, or a desalination system, wherein the chilled water is stored in a separation tank, wherein it can later be used to provide cooling for an air conditioning system for a facility. When desalination is used, the system produces chilled fresh drinking water which can be used for air conditioning, and then used as fresh drinking water. Any exhaust chilled air can be used directly for air conditioning.