US 10,012,448 B2 · Systems and methods for energy storage and retrieval

Abstract

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 net work 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 net work output. Systems of the present disclosure can employ solar heating for improved storage efficiency.

Claims19

Dependent claims

An energy storage and retrieval system, comprising:

a compressor;
a first heat storage unit;
a turbine;
a second heat storage unit;
a working fluid that flows along a fluid flow path in a closed cycle including, in sequence, the compressor, the first heat storage unit, the turbine, and the second heat storage unit;
and
an auxiliary tank comprising the working fluid, wherein the auxiliary tank is in fluid communication with the fluid flow path of the closed cycle;
and
wherein the system alternately operates as both (i) a heat engine to provide mechanical work from heat and (ii) as a heat pump to use mechanical work to store heat, and
wherein the working fluid flows through, in sequence and in the same direction, the compressor, the first heat storage unit, the turbine, and the second heat storage unit when the apparatus operates as the heat engine and when the apparatus operates as a heat pump.

7 more elements

A method for storing and releasing energy, the method comprising:

(a) increasing the pressure of a working fluid, operating in a closed cycle comprising a fluid flow path configured to circulate the working fluid, from a first pressure to a second pressure with the aid of a compressor, thereby increasing the temperature of the working fluid;
(b) using a first heat storage unit downstream of the compressor and in thermal communication with the working fluid for (i) in a storing mode, removing heat from the working fluid and decreasing the temperature of the working fluid, which decrease in temperature is at substantially the second pressure, or (ii) in a releasing mode, supplying heat to the working fluid and increasing the temperature of the working fluid, which increase in temperature is at substantially the second pressure;
(c) decreasing the pressure of the working fluid from the second pressure to the first pressure with the aid of a turbine, thereby decreasing the temperature of the working fluid;
(d) using a second heat storage unit downstream of the turbine and in thermal communication with the working fluid for (i) in a storing mode, supplying heat to the working fluid and increasing the temperature of the working fluid, which increase in temperature is at substantially the first pressure, or (ii) in a releasing mode, removing heat from the working fluid and decreasing the temperature of the working fluid, which decrease in temperature is at substantially the first pressure;
and
(e) with the aid of a recuperator in fluid communication with the fluid flow path, supplying heat to the working fluid or removing heat from the working fluid, wherein the working fluid does not undergo a phase change,
wherein the working fluid flows through, in sequence, the compressor, the first heat storage unit, the recuperator, the turbine, the second heat storage unit, and the recuperator in the storing mode,
wherein the working fluid flows through, in sequence, the compressor, the recuperator, the first heat storage unit, the turbine, the recuperator, and the second heat storage unit in the releasing mode, and
wherein the working fluid flows in the same direction in both the storing mode and the releasing mode.

6 more elements

Dependencies are inferred from the claim text.

Systems and methods for energy storage and retrieval

Life of this patent

Systems and methods for energy storage and retrieval

Life of this patent

Abstract

Claims19