Thermal Energy Storage
- Optimized design of a TES unit for the AA-CAES operating conditions to give high efficiency and low material cost.
- Development of simplified storage models for AA-CAES unit design.
- Evaluation of diverse materials for high-temperature sensible TES.
Preliminary Storage configuration
- Length 10m, diameter 6m, solids content 460 tons
- Length 260m, diameter 10m
- 1 kg/s
TES storage efficiency
- Greater than 90%
Applicability of rocks, concrete, and ceramics as sensible thermal energy storage material
Temperature-dependent thermophysical properties were used to compare the different materials in a test scenario.
- Ceramics show the best thermodynamic performance.
- Concrete shows the worst thermodynamic performance.
- Rocks show thermodynamic performance similar to ceramics with much lower costs.
Design & optimization of storage unit for proposed thermodynamic cycle and cavern
- TES length
- Cover insulation thickness
- Particle diameter
- Material costs
- Exergy efficiency
- and min. air outflow temperature
- Existing conventional methods are not applicable to provide required air-tightness of the TES because of the high temperature conditions.
- Lining for the TES has to ensure sufficient thermal insulation to reduce the heat losses.
- This can be achieved by use of multilayer lining: