With an efficient heat-storage concept, the efficiency of an AA-CAES plant is projected to reach 75 percent. The economics will depend on grid-related factors, as well as plant cost, size and cycle efficiency. Similarly, the net CO2 impact will depend on the CO2 content of the marginal generation units during charging and discharging cycles. The basic concept of compressed air energy storage has been proven with the plants in Huntorf, Germany (321 MW) and McIntosh, USA (110 MW) that have been operating since 1978 and 1991 respectively.
The overall objectives of the joint project are: (1) to demonstrate a combined sensible/latent-heat storage at an industrially relevant scale for use in AA-CAES and (2) to assess the environmental and economic potential of AA-CAES as an alternative to pumped hydropower storage in Switzerland. Efficient heat storage is the key enabling technology for AA-CAES and therefore the central focus of this project, which will study the use of combined sensible/latent-heat storage and examine the following four issues:
- Concept and optimisation of high-temperature combined sensible/latent-heat storage
- Analysis of AA-CAES cycles exploiting combined sensible/latent-heat storage
- Stable and efficient aluminium-silicon-based phase-change material structures for high-temperature latent-heat storage
The target audiences are companies in the areas of power generation, heat storage, tunnel and cavern construction, and materials manufacturing, as well as energy utilities, commercial and academic research institutions, and cantonal and federal policy and decision-makers.
Increased reliance on intermittent renewable energy sources will require additional energy storage. AA-CAES is a complementary alternative to pumped hydropower storage that is particularly attractive for Switzerland for several reasons:
- The environmental impact of AA-CAES is lower than that of pumped hydropower.
- Pre-existing, unused tunnels and military caverns could be used as high-pressure storage reservoirs.
- Swiss industry possesses unparalleled tunnel construction expertise that could be exploited to build additional storage facilities.
- Under certain circumstances, an AA-CAES plant is estimated to be cheaper to construct than a pumped hydropower plant.
High-Temperature Combined Sensible/Latent-Heat Storage Based on Novel Materials for Electricity Storage Using Advanced Adiabatic Compressed Air Energy Storage
The joint project consists of three research projects
Design and Optimization of High-Temperature Combined Sensible/Latent-Heat Storage
- Dr. Andreas Haselbacher, Departement für Maschinenbau und Verfahrenstechnik, ETH Zürich; Dr. Peter Burgherr
Analysis of AA-CAES cycles exploiting Combined Sensible/Latent Thermal Energy Storage and Novel Materials
- Dr. Maurizio Barbato, Dipartimento Tecnologie Innovative (DTI), Scuola universitaria professionale della Svizzera italiana, Manno; Dr. Peter Burgherr, Paul Scherrer Institut
Aluminium-silicon based phase change material structures for high-temperature latent heat storage
- Prof. Sophia Eva Martha Haussener, Laboratoire de la science et de l'ingénierie de l'énergie renouvelable, EPF Lausanne; Dr. Peter Burgherr, Prof. Andreas Mortensen, Dr. Ludger Weber
