A local solar heating plant on the Danish island of Samsoe. 100% of the electricity in the island is provided by wind turbines, 70% of the heat supply comes from four sustainable district heating plants. A large amount of small private systems also contribute to the production of renewable energy. When the heating requirement cannot be covered by the sun, a wood chip boiler will supplement the requirement. Two Danish islands, Samsoe and Aeroe became the first of Denmark's official renewable energy islands.