news / 2013-09-10

Smart Region Pellworm: An island becomes power-independent

Pellworm annually produces around 21 gigawatt-hours of renewable energy. Source: Schleswig-Holstein Netz AG

With around 21 gigawatt-hours, Pellworm annually produces three times as much power as it consumes. Even so, the 1,200 people living on the island are reliant on power deliveries via two 20-kilovolt submarine cables from the land grid. With a combination of wind power, photovoltaics and biogas plants with large-scale storage facilities, home storage systems and intelligent measurement technology, the island is now due to become self-sufficient in terms of power.


Eon and Schleswig-Holstein Netz AG erected a storage system and used data connections to couple the customers’ electricity connections to the wind turbines and photovoltaic systems on the island. If excess power is generated when the wind and sun are strong, it flows into the large-scale storage system with lithium-ion and redox flow batteries, and into decentralised home storage systems. Under low wind conditions and when the sky is cloudy, the island residents use the power from these batteries. Controllable local grid transformers, special power electronics and an energy management system have been integrated into the electricity grid in order to improve control of the energy flows.


“Our aim is to couple power generation and consumption in such a way that we can make better use of the energy system, so that it continues to perform effectively while remaining affordable. The more successful this project is, the more energy can be used locally, and the more independent the island becomes from long-distance energy transports,” explains Matthias Boxberger, board member at Schleswig-Holstein Netz AG, summarising the goals of the “Smart Region Pellworm” research project. “With the expansion of renewable energy in Germany, we increasingly have a situation where supply exceeds demand for power to a growing degree when the wind is strong or the sun is shining brightly. As a result, the electricity grid is increasingly reaching the limit of its capacity,” says Leonhard Birnbaum, member of the board at Eon. “We still have a lot to learn and gain a lot more experience. The Smart Region Pellworm is a very clear example of how highly promising solutions could look for the energy supply system of the future.”

The large-scale storage system is located directly next to the solar farm on Pellworm. Source: Eon Hanse AG

The project, with an investment volume of almost ten million euros, is being implemented by an innovation group of specialists from industry and science. It is being funded as part of the energy storage initiative initiated by the German Federal Ministry of Economics and Technology, the German Federal Ministry for Education and Research and the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety.


Stand-alone solutions can be implemented for private consumers in rural areas

One of the focuses of the research project is to investigate how long-distance electricity transport and the grid expansion this requires can be reduced. A study by the German Federal Environment Agency shows that stand-alone solutions are particularly suitable for rural settlement areas in northern Germany. In particular, the electricity requirement by the industrial and commercial sectors can hardly be covered in many regions. The key, according to a study entitled “Modellierung einer vollständig auf erneuerbaren Energien basierenden Stromerzeugung im Jahr 2050 in autarken, dezentralen Strukturen”, is a well-developed electricity grid for the regional compensation of electricity production and consumption.

Project participants

Operator of the generation systems
Eon New Build & Technology GmbH

Extension of the system platform
Schleswig-Holstein Netz AG

Assessment of the storage facilities
Fachhochschule Westküste (FHW)

Operational planning of the energy systems
Fraunhofer-Institut für Optronik, Systemtechnik und Bildauswertung

Operational management of the storage systems
Fraunhofer UMSICHT

Power electronics
Gustav Klein GmbH & Co. KG

Development of business models
Rheinisch-Westfälische Technische Hochschule Aachen (RWTH)

Manufacturer of the lithium-ion battery system
Saft Batterien GmbH