Joint project "Electricity storage via adiabatic air compression"


This joint project aims to carry out an integrated examination along a value chain of advanced adiabatic compressed air energy storage (AA-CAES), the only large-scale energy storage concept that at present has the potential to complement pumped hydropower storage in Switzerland. It will develop the science and technology, and examine the environmental and economic impacts.




Prof. Sophia Haussener wins Prix ZontaProf. Sophia Haussener wins Prix Zonta 11:00:00 PM

Project description (ongoing research project)

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:

  1. The environmental impact of AA-CAES is lower than that of pumped hydropower.
  2. Pre-existing, unused tunnels and military caverns could be used as high-pressure storage reservoirs.
  3. Swiss industry possesses unparalleled tunnel construction expertise that could be exploited to build additional storage facilities.
  4. Under certain circumstances, an AA-CAES plant is estimated to be cheaper to construct than a pumped hydropower plant.

Original title

High-Temperature Combined Sensible/Latent-Heat Storage Based on Novel Materials for Electricity Storage Using Advanced Adiabatic Compressed Air Energy Storage

Principal Investigators

Leader of the joint project

  • Prof. Aldo Steinfeld, Institut für Energietechnik, ETH Zürich

Deputy leader of the joint project

  • Dr. Maurizio Barbato, Dipartimento Tecnologie Innovative, Scuola universitaria professionale della Svizzera italiana, Manno


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



Further information on this content


Prof. Aldo Steinfeld Institut für Energietechnik
ETH Zürich
Sonneggstrasse 3
Gebäude ML
8092 Zürich +41 44 632 79 29

Products of the project