Denmark - Direct Uses




Geothermal heating plant in Thisted



Geothermal heating plant in Copenhagen



Geothermal heating plant in Sonderborg



Ground source geothermal heat pumps





Total thermal installed capacity in MWt


Direct use in TJ/year


Direct use in GWh/year


Capacity factor



Country Update: The country has three geothermal plants with deep wells producing heat for district heating. Other projects are at different levels of maturation. The first geothermal heating plant started production in Thisted in 1984 and now has a capacity of 7 MWt (75 TJ/yr) from 43oC saline water from the Gassum reservoir at 1.25 km depth. A plant in Copenhagen at 14 MWt (180 TJ/yr) operating from 74°C saline water from a well at 2.6 km depth started production in 2005 from the Bunter Sandstone reservoir. The latest plant, at up to 12 MWt (100 TJ/yr) using 48oC saline Gassum formation water from 1.2 km depth, started production at Sønderborg in 2013. The plants have one production and one injection well producing heat from the sandstone reservoirs through heat exchanger and/or Lithium-bromine based absorption heat pumps. The driving heat primarily comes from biomass boilers for heat and/or combined heat and power production. Shallow geothermal is mainly used for domestic heating via arrays of closed loops about one meter depth in combination with heat pumps. Closed loop boreholes to around 150 m depth are also beginning to be used for domestic heating, both for single houses, for smaller collective networks, and for heating large office buildings. Borehole Thermal Energy Storage (BTES) for seasonal storage of heat is applied in a test plant at the district heating network in Broedstrup. Few installations use a groundwater aquifer for heating, cooling or seasonal storage (ATES). The number of small ground source heat pumps extracting shallow geothermal heat has been assessed to around 27,000 with an installed capacity of 320 MWt and annual energy use of 3,400 TJ/yr. The total for the country is then 353 MWt and 3,755 TJ/yr (Røgen, et al., 2015).

Taken from: John W. Lund and Tonya L. Boyd
Published in Direct Utilization of Geothermal Energy 2015 Worldwide Review

Total thermal installed capacity in MWt:200
Direct use in TJ/year2,500
Direct use in GWh/year694.5
Capacity factor0.4

Temperatures in the country are of low-enthalpy with no pronounced temperature anomalies, with normal gradients of 25 to 30oC/km. Two large district heating plants using heat pumps have been built in the country.

The first was established in 1984 at Thisted producing 44oC saline water at 200 m3/h from 1,250 m depth resulting in 7 MWt of installed capacity. The second in Copenhagen started in 2005, uses 73oC saline water at 235 m3/h from 2,560 m depth resulting in an installed capacity of 14 MWt. 
These two plants along with other heat pump district heating projects have an installed capacity of 44 MWt and annual energy use of 800 TJ. Additional projects are being investigated for district heating at Sønderborg, Hjørring, and other communities. The plants at Thisted and Copenhagen are being considered for expansion.

A number of small heat pump projects have been installed, estimated at 20,000 units in a vertical configuration with a capacity and annual energy use of 160 MWt and 1,700 TJ/yr. Ground water is also being used for cooling and industrial locations.

The total geothermal capacity is 200 MWt and the annual use is 2,500 TJ. 

Taken from the paper by John W. Lund, Derek H. Freeston, and Tonya L. Boyd: "Direct Utilization of Geothermal Energy 2010 Worldwide Review"; published in Proceedings of the World Geothermal Congress 2010, Bali, Indonesia, 25-29 April 2010