In a world first on 13 June, Siemens Gamesa Renewable Energy began operation of its electric thermal energy storage system (ETES). The technology makes it possible to store large quantities of energy cost-effectively and thus decouple electricity generation and use. The heat storage facility, which was ceremonially opened in Hamburg-Altenwerder, contains around 1000 tonnes of volcanic rock as a storage medium. It is fed with electrical energy converted into hot air by means of a resistance heater and a fan 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.
The storage capacity of the system remains constant throughout the charging cycles. The aim of the pilot plant is to deliver system evidence of storage on the grid and to test the heat storage extensively. In a next step, Siemens Gamesa plans to use the technology in commercial projects and scale up the storage capacity and power.
The goal is to be able to store energy in the range of several GWh in the near future. "Decoupling generation and consumption of fluctuating renewable energy via storage is an essential contribution to implementing the energy system transformation. We therefore need cost-effective, efficient and scalable energy storage systems," commented Andreas Feicht, state secretary at the Federal Ministry of Economics and Energy.
"With the commissioning of our ETES pilot plant, we have reached an important milestone on the way to introducing high-performance energy storage systems” said Markus Tacke, CEO of Siemens Gamesa Renewable Energy.
