Hamburg, Germany, 18 June 2019: In what it described as a world first, Spain-headquartered Siemens Gamesa Renewable Energy (SGRE) on June 12 began operation of its electric thermal energy storage system (ETES), the company said through a Press communiqué. During the opening ceremony, Andreas Feicht, State Secretary, German Federal Ministry of Economics and Energy; Peter Tschentscher, First Mayor of Free and Hanseatic City of Hamburg; Markus Tacke, CEO, Gamesa; and project partners Hamburg Energie GmbH and Hamburg University of Technology (TUHH) welcomed the achievement of the milestone. The innovative storage technology, the communiqué said, makes it possible to cost-effectively store large quantities of energy and, thus, decouple electricity generation and use.

Prof. Dr.-Ing. Gerhard Schmitz, Technical University Hamburg (TUHH); Michael Prinz, Managing Director Hamburg Energie GmbH; Andreas Feicht; Peter Tschentscher and Markus Tacke

According to the communiqué, the heat storage facility, which was ceremonially opened today in Hamburg-Altenwerder, 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, the communiqué said. When demand peaks, ETES uses a steam turbine for the re-electrification of the stored energy, the communiqué said. The ETES pilot plant can, thus, store up to 130 MWh of thermal energy for a week, the communiqué added. In addition, the storage capacity of the system remains constant throughout the charging cycles, the communiqué further added.

The aim of the pilot plant is to deliver system evidence of the storage on the grid and to test the heat storage extensively. In a next step, Siemens Gamesa plans to use its storage technology in commercial projects and scale up the storage capacity and power, the communiqué said. The goal is to store energy in the range of several gigawatt hours (GWh) in the near future, the communiqué added. One gigawatt hour is the equivalent to the daily electricity consumption of around 50,000 households.

Michael Prinz, Andreas Feicht, Peter Tschentscher, Markus Tacke and Prof. Dr.-Ing. Gerhard Schmitz

Speaking on the occasion, Feicht said: “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.”

Tacke added: “With the commissioning of our ETES pilot plant, we have reached an important milestone on the way to introducing high-performance energy storage systems. Our technology makes it possible to store electricity for many thousands of households at low cost. We are, thus, presenting an elementary building block for the further expansion of renewable energy and the success of the energy transition.” The technology reduces costs for larger storage capacities to a fraction of the usual level for battery storage, the communiqué said.

According to the communiqué, the Institute for Engineering Thermodynamics at Hamburg University of Technology and the local utility company, Hamburg Energie are partners in the innovative Future Energy Solutions project, which is funded by the German Federal Ministry of Economics and Energy within the “6. Energieforschungsprogramm” research programme. TU Hamburg carries out research into the thermodynamic fundamentals of the solid bulk technology used, the communiqué said.

By using standard components, it is possible to convert decommissioned conventional power plants into green storage facilities (second-life option), the communiqué said. Hamburg Energie is responsible for marketing the stored energy on the electricity market. The energy provider is developing highly flexible digital control system platforms for virtual power plants, the communiqué added. Connected to such an IT platform, ETES can optimally store renewable energy at maximum yield, the communiqué further added.