Pumped Thermal Energy Storage (PTES)
Engineered to Fill the LDES Gap to Enable the Global Energy Transition.
Low cost — Offers a lower levelized cost than currently available technology CapEx, OpEx and end of life.
Scalable — No topographical or geologic dependencies; can be built anywhere with a fully domestic supply chain.
Flexible — Modular solution that can uniquely serve high power needs at both medium and longer GWh durations. Provides grid inertia and other ancillary services.
Innovative Design Coupled With Tested Technology
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Example PTES Site Layout
Advanced Supercritical Carbon Dioxide (sCO2) Technology
- Efficient heat pump and heat engine cycle
- Echogen is a world leader developing sCO2 systems for power generation
Unique, Patented Thermal Storage Solution
- Engineered concrete thermal batteries
- Low-cost materials
Proven Components
- Power turbine and low-temperature compressor are derivatives of existing designs
- Heat exchangers, piping, valves, controls are of similar design to existing sCO2 systems
- Printed Circuit Heat Exchangers (PCHE)
Proven Technology
Leveraging Existing Equipment and Known Components
Thermodynamic cycles transform energy between electricity and heat
Charging Cycle (Heat Pump)
- Supercritical CO2 heat pump (refrigeration) cycle
- Uses electrical power to move heat from a cold reservoir to a hot reservoir
- Creates stored energy as both “heat” and “cold”
Generating Cycle (Heat Engine)
- Supercritical CO2 heat engine (power) cycle
- Uses heat stored in hot reservoir to generate electrical power
Application Example