Technical Development and Economic Evaluation of the Integration of Thermal Energy Storage in Steam Power Plants

Grid-compliant integration of renewable energies will in future require considerable increases in flexibility in the operation of conventional power plants. The integration of thermal energy storage systems (TES) into the power plant process can create considerable improvements, for example, in the speed of load change and partial load behavior. In the case of existing plants, there are thus good prospects of upgrading for more flexible operation, which promises improvements in the energy system that can be achieved in the relatively short term. The aim of this publication is, therefore, to identify integration options for TES in coal-fired power plants which would enable the desired high flexibility potentials and, at the same time, include cost-efficient solutions. By means of an iterative approach between future scenarios of the energy market, the power plant process, and the TES component, favored configurations were developed from a wide range of integration concepts. For this purpose, thermodynamic simulation studies were performed, operating concepts were developed, economic assessments were made, design calculations were performed, and experimental investigations on different TES options were realized. The results obtained can serve as a basis for the demonstration of a promising TES technology in an existing hard coal-fired power plant