Smart grids can link renewable energy sources and battery storage systems to provide a secure and stable power supply to a region based on wind and solar energy alone, also for the long term. This is the result of the first phase of the Smart Region Pellworm research project in which E.ON teamed up with his grid operator Schleswig-Holstein Netz AG, the two Fraunhofer institutes IOSB-AST and UMSICHT, the power systems manufacturer Gustav Klein GmbH & Co. KG, the battery manufacturer Saft Batterien GmbH, the Fachhochschule Westküste as well as RWTH Aachen University to operate the first smart electricity grid on the island of Pellworm in northern Germany.
In the second phase of the project, which is about to start, E.ON and its partners will explore new business models on the North Sea island to find a way of making battery-based power solutions commercially viable. There are also plans to integrate this technology into the existing virtual power plant operated by E.ON subsidiary HanseWerk Natur.
In the past, Pellworm produced much more wind and solar power than was needed on island. Nevertheless, because of the intermittent nature of renewables, it was often necessary to import energy via two subsea cables from the mainland. It was therefore important to find ways of buffering the fluctuating supply of these intermittent energy sources and improve utilisation on the island. To do so, E.ON built a dedicated power supply system comprising two large electrical batteries as well as thermal storage units which were integrated into a novel energy management system to connect the customers on the island to the wind and solar power installations.
Following the successful test phase, the second project phase will now focus on optimising the economics, which are still a challenge. Improved system performance, greater economies of scale and price discounts are expected to compensate for the high capex for the storage systems.