Sustainable Energy Successees

   

Stirling Engine, Solar & Efficient Heat for Eco-village in Hjortshøj, Denmark.

An outstanding heating heating system for an eco-village of 105 households with wood-chip and wood pellet boilers, a small (35 kW electric) combined heat and power plant with a stirling engine, solar heating. For 23 houses also pulsating district heating to reduce heat losses in the network.

The Ecovillage "Andelssamfundet i Hjortshøj" is an intentional community started in 1991 on the edge of the village Hjortshøj near the Danish smaller city "Århus". The aims include to allow interested people from the Århus area to live a more environmental lifestyle including use of local renewable energy supply, and to create a living space with more community activities than normally found in suburbs.
To realise the ideas of local energy, the community members decided to form a heating cooperative and to interconnect the house groups of the eco-village with a heat network. Now the heat network supplies the houses from a heating station in the eco-village. It was also decided to build all houses as low-energy houses with solar heating for hot water. The solar heating allows the central system to be switched off during summer months, reducing network losses.

Until 2002, the heating was provided by a wood pellet boiler, but then it was decided to increase the heating station with a wood-chip boiler and a stirling engine for combined heat and power production.

In 2008, it was decided to supply 23 houses in an extension of the eco-village with an innovative heat supply, where heat is only provided part of the day. During that period a heat tank in each house is charged to store heat for the rest of the day. This saves up to 50% of the heat loss in the network. All the new houses are detached, low-energy houses, and the network losses are therefore potentially large compared with useful heat delivered to the houses.

Future plans include to measure performance of the systems, buy an electric car for the community car-sharing club, and to buy solar PV that can produce electricity in the summer, when the stirling engine is off.

Read longer description (2 pages, 76 kB pdf)

See the Hjortshøj eco-village own website