An engine assembly is provided with a split-cycle internal combustion engine having a compression section and an expansion section and with a cooling circuit for circulating a heat-exchange fluid; said fluid has a boiling temperature such that at least a fraction of the fluid changes phase from liquid to vapour flowing through the expansion section of the engine, when the latter operates in steady conditions; the circuit comprises a turbine arranged downstream of the engine so as to receive vapour and produce mechanical energy from the expansion of the vapour.

An engine assembly is provided with a split-cycle internal combustion engine having a compression section and an expansion section and with a cooling circuit for circulating a heat-exchange fluid; said fluid has a boiling temperature such that at least a fraction of the fluid changes phase from liquid to vapour flowing through the expansion section of the engine, when the latter operates in steady conditions; the circuit comprises a turbine arranged downstream of the engine so as to receive vapour and produce mechanical energy from the expansion of the vapour.

Traditional power generation with a turbine may be inefficient, costly or inconvenient. The improvement disclosed herein involves the use of two fluids. A pressurizing fluid is vaporized, pressurized and fed into a pressure cylinder holding a liquid working fluid. The pressurizing fluid forces the working fluid out of the pressure cylinder and through a liquid turbine to generate electricity or perform work. The working fluid is recycled from the turbine into another pressure cylinder for re-use. The pressurizing fluid is condensed and then also recycled back to the evaporator where it is vaporized and pressurized again. Use of a liquid rather than gas turbine makes for improved efficiency and lower cost. The use of a separate pressurizing fluid, which may be volatile, allows for convenient use where the temperature of the thermal source is limited.

The present disclosure provides pumped thermal energy storage systems that can be used to store electrical energy. A pumped thermal energy storage system of the present disclosure can store energy by operating as a heat pump or refrigerator, whereby network input can be used to transfer heat from the cold side to the hot side. A working fluid of the system is capable of efficient heat exchange with heat storage fluids on a hot side of the system and on a cold side of the system. The system can extract energy by operating as a heat engine transferring heat from the hot side to the cold side, which can result in network output. Systems of the present disclosure can employ solar heating for improved storage efficiency.

The present disclosure provides pumped thermal energy storage systems that can be used to store electrical energy. A pumped thermal energy storage system of the present disclosure can store energy by operating as a heat pump or refrigerator, whereby network input can be used to transfer heat from the cold side to the hot side. A working fluid of the system is capable of efficient heat exchange with heat storage fluids on a hot side of the system and on a cold side of the system. The system can extract energy by operating as a heat engine transferring heat from the hot side to the cold side, which can result in network output. Systems of the present disclosure can employ solar heating for improved storage efficiency.

A method including: (i) operating a pumped-heat energy storage system (“PHES system”) in a charge mode to convert electricity into stored thermal energy in a hot thermal storage medium (“HTS medium”) by transferring heat from a working fluid to a warm HTS medium, resulting in a hot HTS medium, wherein the PHES system is further operable in a generation mode to convert at least a portion of the stored thermal energy into electricity; and (ii) heating the hot HTS medium with an electric heater above a temperature achievable by transferring heat from the working fluid to the warm HTS medium.

An energy storage plant includes a casing for the storage of a working fluid other than atmospheric air, in a gaseous phase and in equilibrium of pressure with the atmosphere; a tank for the storage of said working fluid in a liquid or supercritical phase with a temperature close to the critical temperature; wherein said critical temperature is close to the ambient temperature. The plant is configured to carry out a closed thermodynamic cyclic transformation, first in one direction in a charge configuration and then in the opposite direction in a discharge configuration, between said casing and said tank; wherein in the charge configuration the plant stores heat and pressure and in the discharge configuration generates energy.

The present disclosure provides pumped thermal energy storage systems that can be used to store electrical energy. A pumped thermal energy storage system of the present disclosure can store energy by operating as a heat pump or refrigerator, whereby network input can be used to transfer heat from the cold side to the hot side. A working fluid of the system is capable of efficient heat exchange with heat storage fluids on a hot side of the system and on a cold side of the system. The system can extract energy by operating as a heat engine transferring heat from the hot side to the cold side, which can result in network output. Systems of the present disclosure can employ solar heating for improved storage efficiency.

The present disclosure provides pumped thermal energy storage systems that can be used to store electrical energy. A pumped thermal energy storage system of the present disclosure can store energy by operating as a heat pump or refrigerator, whereby network input can be used to transfer heat from the cold side to the hot side. A working fluid of the system is capable of efficient heat exchange with heat storage fluids on a hot side of the system and on a cold side of the system. The system can extract energy by operating as a heat engine transferring heat from the hot side to the cold side, which can result in network output. Systems of the present disclosure can employ solar heating for improved storage efficiency.

Thermal energy storage systems are disclosed in this application. Systems of the inventive subject matter are designed to reduce maintenance requirements by sequestering, for example, corrosive fluids that might otherwise damage difficult-to-fix internal components are kept out of those components by introducing a non-corrosive heat transfer fluid to facilitate heat transfer between a thermal energy storage medium (e.g., molten sulfur) and a potentially corrosive working fluid. Thus, the potentially corrosive fluid is kept out of a thermal energy storage tank containing the thermal energy storage medium, which, by design, is difficult to repair when internal components corrode or otherwise require maintenance.