Siemens Gamesa Renewable Energy (SGRE) said that is has begun operation of its electric thermal energy storage system (ETES), a milestone in the development of energy storage solutions, according to the company.
The heat storage facility is located in Hamburg-Altenwerder and contains around 1,000 tonnes of volcanic rock as an energy storage medium. It is fed with electrical energy converted into hot air by means of a resistance heater and a blower that heats the rock to 750°C. When demand peaks, ETES uses a steam turbine for the re-electrification of the stored energy. The ETES pilot plant can thus store up to 130 MWh of thermal energy for a week. In addition, the storage capacity of the system remains constant throughout the charging cycles.