AA-CAES – Opportunities and challenges of advanced adiabatic compressed-air energy storage technology as a balancing tool in interconnected grids

An expansion of CO2-neutral energy supply is in the focus of European and national environmental policy and will be crucially supported by offshore wind power generation in future. Grid-compatible integration of these fluctuating electricity quantities will - in the medium term already - require substantial adjustments of the German grid and power plant system in order to cope with the upcoming new boundary conditions. The development of new technologies for large-scale electricity storage is a key element in future flexible European electricity transmission systems. Electricity storage in Adiabatic CAES power plants offers the prospect of making a substantial contribution to reach this goal. This concept allows efficient, local zero-emission electricity storage on the basis of compressed air in underground caverns. The compression and expansion of air in turbomachinery help to balance power generation peaks that are not demand-driven on the one hand and consumption-induced load peaks on the other. Before this concept can be implemented, however, several technical problems must be solved and technical development work done, especially in the field of turbomachinery and the required heat storage device. This paper outlines the technical possibilities and the need for development. Ongoing development activities are described and first interim results presented