Electro-thermal energy storage (ETES) offers key advantages over other advancing technologies. For example, Chemical battery solutions have limitations (cost, performance, cycles, materials, environmental, health & safety, degradation, etc.) which are exacerbated as storage duration requirements lengthen.
- Low capital cost
- No augmentation costs
- Higher projected reliability
- Low environmental impact
Capital Cost and LCOS
ETES capital cost and levelized cost of storage (LCOS) compares very favorably versus li-ion battery systems, with increasing advantage as storage time increases above 6 hours.
Echogen ETES sand and concrete storage materials are relatively benign to operate and dispose of. This is a contrast to the many metal chemistries of fixed and flow electrolyte batteries, as well as more exotic storage materials of other ETES systems. Thus, the Echogen ETES system maintains a low environmental footprint through its value chain.
- CO2 is the best fluid for ETES, providing high-performance, low cost and low impact
- Charging: CO2 is one of the first heat pump fluids ever used (charging cycle), and condenses near 0°C
- Generating: CO2 power cycles are commercially available today
- CO2 properties allow for high round-trip efficiency (> 60%) while using low-cost materials