Thermal Energy Storage - Generation

Basic Technology Characteristics Image source: Caldwell Tanks
How it Works:	Storing energy by heating or cooling a storage medium and converting to electricity.
Benefits:	Low cost incremental energy Non-toxic materials Can be integrated with existing power gen units
Challenges:	Low round trip efficiency  System engineering challenges to enable low cost installations
Technology Variations:
Applications:	Molten Salt, Liquid Air, Concrete/Gravel/Sand Thermal, Electro-Thermal Energy Storage Used for bulk energy storage applications
AC RTE Efficiency:	35-60%
Cycle Life:	20 - 30 years
Technology Readiness Level (TRL):	4 to 9 - Varied
Installed Capacity:	~4 GW (mostly molten salt)