Methods and systems for energy storage and management are provided. In various embodiments, heat pumps, heat engines and pumped heat energy storage systems and methods of operating the same are provided. In some embodiments, methods include controlling thermal properties of a working fluid by virtue of the timing of the operation of cylinder valves. Methods and systems for controlling mass flow rates and charging and discharging power independent of working fluid temperature and system state-of-charge are also provided.

Methods and systems for energy storage and management are provided. In various embodiments, heat pumps, heat engines and pumped heat energy storage systems and methods of operating the same are provided. In some embodiments, methods include controlling thermal properties of a working fluid by virtue of the timing of the operation of cylinder valves. Methods and systems for controlling mass flow rates and charging and discharging power independent of working fluid temperature and system state-of-charge are also provided.

A refrigeration appliance includes a refrigeration circuit having a condenser and a heat circulation system for heating an element of the refrigeration appliance. The heat circulation system includes a heat conducting region. A heat exchanging element includes the condenser and the heat conducting region. The condenser and the heat conducting region in the heat exchanger element are thermally coupled in order to output heat from the refrigeration circuit to the heat conducting region of the heat circulation system.

A refrigeration appliance includes a refrigeration circuit having a condenser and a heat circulation system for heating an element of the refrigeration appliance. The heat circulation system includes a heat conducting region. A heat exchanging element includes the condenser and the heat conducting region. The condenser and the heat conducting region in the heat exchanger element are thermally coupled in order to output heat from the refrigeration circuit to the heat conducting region of the heat circulation system.

A system and method for providing dry cooling of a source liquid, having a plurality of heat exchangers which depolymerize and polymerize a polymer. Specifically, the depolymerization process is endothermic and draws heat from a source liquid in a first heat exchanger, and the polymerization process is exothermic and expels heat from a second heat exchanger. Additional heat exchangers and holding tanks may be incorporated in the system and method. In some embodiments the system further provides additional cooling of the polymer prior to depolymerization using cooler night ambient air.

A system and method for providing dry cooling of a source liquid, having a plurality of heat exchangers which depolymerize and polymerize a polymer. Specifically, the depolymerization process is endothermic and draws heat from a source liquid in a first heat exchanger, and the polymerization process is exothermic and expels heat from a second heat exchanger. Additional heat exchangers and holding tanks may be incorporated in the system and method. In some embodiments the system further provides additional cooling of the polymer prior to depolymerization using cooler night ambient air.

A district public water supply pipe network system compatible for ground source heat pump water and reclaimed water comprises a water supply main pipe connected with a reclaimed water outlet side of a sewage treatment system and connected to a plurality of energy stations and a plurality of transmission and distribution station, and a return water main pipe arranged between the adjacent energy stations to connect them. The energy stations are provided with a plurality of shallow geothermal heat exchange system for exchanging heat with shallow geothermal energy in the region. Both the energy stations and the transmission and distribution station are connected with corresponding distribution pipe networks connected with a user terminal water supply system. The system provides the source side water and the reclaimed water to users. It is a district public geothermal pipe network and a reclaimed water pipe network.

An optimized heating and cooling system including a thermal mass, thermal energy transport conduits to deliver thermal energy to the thermal mass including one or more phase change materials (PCMs), at least one heat exchanger to exchange the thermal energy from a energy input into heat transfer fluid that is pumped through the thermal mass. The system also includes a controller in electronic communication with a temperature sensor, a throttle and a pump. A desired building temperature profile, a daily temperature forecast, the electricity rates, the thermal characteristics of the PCMs are entered into or obtained by the controller and the controller uses that information to optimize the energy use to avoid using the heating and cooling system during peak electricity demand time, or uses the rate structure to determine the operation sequence that results in the most efficient use of energy or least cost.

An optimized heating and cooling system including a thermal mass, thermal energy transport conduits to deliver thermal energy to the thermal mass including one or more phase change materials (PCMs), at least one heat exchanger to exchange the thermal energy from a energy input into heat transfer fluid that is pumped through the thermal mass. The system also includes a controller in electronic communication with a temperature sensor, a throttle and a pump. A desired building temperature profile, a daily temperature forecast, the electricity rates, the thermal characteristics of the PCMs are entered into or obtained by the controller and the controller uses that information to optimize the energy use to avoid using the heating and cooling system during peak electricity demand time, or uses the rate structure to determine the operation sequence that results in the most efficient use of energy or least cost.

A heat exchanger includes at least one flat tube configured to allow a refrigerant mixture inclusive of HFO1123, R32, and HFO1234yf to flow therethrough as a heat medium. The flat tube includes a plurality of flow paths for the heat medium. Each of the plurality of flow paths has a round rectangular shape in cross section, the round rectangular shape being defined by a pair of longitudinal line segments opposed to each other, a pair of lateral line segments opposed to each other, and a set of four rounded corners, each of the rounded corners being a segment of a circumference of a circle. The pair of longitudinal line segments are intersects with the pair of lateral line segments at the rounded corners. The round rectangular shape is configured to satisfy 0.005≦r/d≦0.8 where r is a radius of the circle, and d is a distance between the pair of longitudinal line segments opposed to each other.