In Sweden large heat pumps in the 10 MW range have been in operation in district heating networks for more than a year. These heat pumps utilize low energy sources like treated sewage water from communities, industrial waste water and lake water. In the southernmost part of Sweden projects are now under way where geothermal energy in combination with heat pumps will be used for production of district heat for this region. The size of the project is about 60 MW of heat