Fossil Energy saved by Spanish renewable energy giant and offshore wind energy leader. Siemens Gamesa Renewable Energy, is developing an electrothermal energy storage system that can store up to 130 megawatt-hours of electricity for a week in volcanic rock.
The ETES (Electric Thermal Energy Storage) solution
Siemens Gamesa, a company best known for its offshore wind turbines, is also a manufacturer of large-scale renewable energy technologies. One of the new business areas is energy storage, Clean Technica explains. In early June 2019, the company announced the start of operations for its Electric Thermal Energy Storage System (ETES), which the company claims is a world first. The pilot plant for this system is located in Hamburg-Altenwerder, Germany.
“With the commissioning of our ETES pilot plant, we have taken an important step on the road to introducing high-performance energy storage systems,” Markus Tacke, CEO of Siemens Gamesa Renewable Energy, told Clean Technica. “Our technology enables the storage of electricity for several thousand households at low cost. In this way, we present a building block for the further expansion of renewable energy and the success of the energy transition.”
Storing energy to redistribute it
Recharge News reports that the ETES (Electrical Thermal Energy Storage) pilot plant in Hamburg converts electrical energy into hot air using a resistance heater and blower to heat about 1,000 tons of volcanic rock to 750°C. If necessary, the plant converts the stored thermal energy back into electricity using a steam turbine. With efficient insulation, heat can be stored for a week or more – at a fraction of the cost of battery storage. Siemens Gamesa claims that the pilot plant can store up to 130 MWh for a week, which will be sold on the market by the local company Hamburg Energie.
“The objective of the pilot installation is to provide evidence of grid storage and to test heat storage extensively,” Siemens Gamesa said in a statement. “In the next step, Siemens Gamesa plans to use its storage technology in commercial projects and increase the storage capacity and power. The goal is to store energy in the order of several GWh in the near future. One GWh is equivalent to the daily electricity consumption of about 50,000 households.”
ETES could give a second life to coal-fired power plants.
The ETES thermal battery can offer coal-fired power plants a new life as heat and energy storage centers, Hasan Özdem, head of technology and project management for Siemens Gamesa, told Greentech Media. This means that the idea that renewables are “killing” conventional coal-fired power plants may no longer be accurate.
“It was wind and solar against coal and gas plants,” Özdem said. “We say no. ETES can give these conventional power plants a place in the energy future by turning them into green storage facilities.”
ETES can be easily integrated into conventional power grids, as it reflects a century-old thermal generation technology. With the exception of the storage chamber, everything else is basically what people have been installing in conventional power plants for decades. It is only the water-steam cycle, steam generators, steam turbines and pipes.
“The only problem with coal-fired power plants is that they pollute the environment. That is, indeed, a very big problem. But if you take that away, this technology has been working very efficiently for decades. And the initial costs of these assets are very high. ETES is, at this point, the only way to keep them working sustainably.” Explains Mr. Özdem to Greentech Media.
A legacy thermal power plant is by no means a prerequisite for ETES. They could be installed anywhere with a network connection. Building them on site or near industrial users gives us access to a whole new clientele.