EKZ boosts energy storage in Switzerland

EKZ is developing an 18MW/7.5MWh battery energy storage plant in Volketswil municipality.

The battery energy storage plant will help Swiss utility and power distribution company EKZ (Elektrizitätswerke des Kantons Zürich) to grow its portfolio of renewable energy resources, store electricity during times when generation is high and integrate it into the main grid to meet demand during peak periods.

The energy storage system, claimed to be the largest battery energy storage in Switzerland, is expected to be operational by the first quarter of 2018 and will provide enough electricity to power 400 households for a day.

Marina González Vayá, smart grid specialist at EKZ, said: “The store will provide regulatory power to the Swissgrid national network and thus contribute to the stabilisation of the electricity grid from Lisbon to Istanbul."

The development of the battery energy storage plant has been approved by the municipality of Volketswil and the Swiss Federal Electric Power Inspectorate.

EKZ grid network plans

The project forms part of EKZ’s plan to embrace innovative energy technologies and to modernise and prepare its grid network for future business models and customer demands.

Over the past five years, the energy provider has been operating a 1MW battery energy storage system at Dietikon which was developed in partnership with ABB.LG Chem batteries were used. The project, still operational, performs both behind-the-meter and front-of-meter applications including solar load shifting and primary frequency control.

Although small, the Dietikon system was actually the first battery energy storage system in Europe to provide primary control reserve (PCR) without backing from conventional thermal generation plants. Transmission system operators (TSOs) in Germany, the Netherlands, Austria and Switzerland began a joint ancillary services market for primary control reserve (PCR) in 2015 and EKZ and partners produced a detailed study on the Dietikon project which detailed the battery’s effectiveness in its first years of operation.

The new system will also be used to provide PCR frequency regulation to the grid and will be used on a commercial basis

Michael Koller, head of Technology at EKZ, added: "More and more renewable sources of energy are fed into the grid unpredictably.

"In order to ensure grid stability, such decentralised storage facilities are gaining in importance."

Batteries and pumped hydro complementary

Other than the Dietikon project and a few other lithium-ion, compressed air and flow battery pilots, Switzerland is host to several large-scale pumped hydro projects.

According to EKZ smart grid engineer and project manager Marina González Vayá, while hydro stores large quantities of energy for long periods of time, pumped hydro plants can’t react as quickly to signals as batteries and are located in the mountains away from most urban centres and therefore have an associated cost for power transmission. Therefore, batteries and pumped hydro could be complementary to one another in meeting Switzerland’s changing energy needs, said González in a statement.