Pullach im Isartal is located to the south west of Munich city with a population of approximately 9,000 people.
As part of the Local Agenda 21 initiative, the municipal government began to investigate heat solutions for the town that would:
- Improve security of energy supply
- Reduce energy costs to the town and prevent price volatility
- Reduce carbon emissions
The local government identified the harnessing of geothermal energy from the Bavarian Molasse Basin as a potential solution and commenced a feasibility study. Following a positive feasibility study the project commenced in 2004 with the drilling of two boreholes and the development of a district heating network.
The project commenced in 2004 with two boreholes being drilled to more than 3,500m. It achieved geothermal water with temperatures in excess of 100°C. The district heating network commenced once suitable flow rates and temperatures were established. Initially a 20km network was installed connecting municipal buildings. Once operational the network was extended to connect more than 1,500 customers.
Major users include a public swimming pool, primary and secondary schools, day care centres, housing estates, housing associations (560 flats), a civic centre, a fire station, a church centre, a teacher training college, a youth hostel, and the town hall.
The positive acceptance of geothermal heat by public and private customers of Pullach im Isartal has created a need for more geothermal capacity. Drilling of the third well was commenced in 2011 and completed in 2012, increasing the installed capacity of the system to 15MWth. The network continues to be extended with current customer take up at 90%.