The goal is to obtain an efficient energy storage system for the storage period of 2 to 14 days. Looking at the operating points of the different storage technologies, redox-flow batteries or compressed air storage systems can be considered for this purpose. Since we want to concentrate on consumer-oriented hybrid storage systems, we have decided in favor of compressed air storage. We recognize the significantly greater development potential here, especially for medium-sized commercial enterprises that require process compressed air in addition to energy storage. Here, we expect significantly improved energy efficiency.
The compressed air storage system, as a pure energy storage system, is mainly used between March and October and is intended to compensate for the reduced regenerative generation, e.g. in photovoltaic systems, during the passage of bad weather fronts.
In adiabatic compressed air storage, it is possible to improve the efficiency of the storage system, provided that a thermal cycle is used to remove the heat generated during compression and store it externally. This heat must be returned to the valve/generator in the expansion process. This makes it possible to significantly improve the overall efficiency of the system.
There is a need for development of a special heat exchanger which is able to react to different air pressures, and thus to different amounts of heat or cold, by hydraulic balancing. Air pumps and generators need to be tuned and evaluated. At this stage it is not clear whether this can be done with a combined pump/generator solution or optimized with one inlet and one outlet each. Different compressed air reservoirs are to be investigated, evaluated, and adapted according to both technical and economic aspects.
The compressed air reservoir is to be integrated into the control system of the hybrid storage plant XS by means of suitable measuring sensors and control algorithms.
Heckmann Stahl- und Metallbau Ost GmbH, (n.n. – Unternehmen Wärmetauscher), Convia GmbH
Brandenburgische Technische Universität Cottbus
ZM Mestil Sp. z o.o.