Geothermal district heating in Lendava
Overview
Lendava is a municipality of about 3,000 inhabitants in the eastern part of Slovenia close to the Hungarian and Croatian border. A great number of public buildings such as a school and a kindergarten and several blocks of flats in the town are heated by a geothermal district heating.
The construction of the geothermal system began in 1994 with the drilling of the first well. It taps into an aquifer at about 1.5 kilometers depth which contains up to 60°C warm water. More wells followed and the heating grid as well as the different kinds of heat use have been expanded ever since. Today, the district heating has a length of over 3 kilometers.
The spa Terme Lendava is also heated with thermal water from three wells with the water being used in cascades for space heating, sanitary water heating, bathing, and pools.
Electricity production
In 2023, the construction of a pilot geothermal power plant was started using an existing 3km deep, non-productive gas well. The plant started electricity production in April 2024. If the pilot project is successful, the technology can be used for other abandoned oil and gas wells in Slovenia and elsewhere. The project was financed by the EEA Financial Mechanism with €660,000, the Slovenian state with €109,000 and by Dravske elektrarne Maribor (DEM) with €167,000. DEM is a Slovenian hydropower producer also responsible for the construction of the geothermal plant.
“The innovative pilot project can represent an important milestone for the generation of carbon-free geothermal energy by using abandoned gas and oil wells in Slovenia and throughout the world. It is also an exceptional development opportunity for the Pomurje region.”
Other uses
After having been used for the district heating or spa, the thermal water is still warm enough to be utilized for the de-icing of sidewalks and two football pitches. Furthermore, some existing oil wells have been recommissioned for geothermal and today supply heat to local greenhouses.
“We started with procedures and activities for the use of geothermal energy in Lendava many years ago and used it in tourism, agriculture and district heating, and now the possibilities for obtaining electricity are also opening up.”
Summary
District heating since 1997
Installed geothermal capacity: 1,410 MWth
Gross heat production: 7,237 GWh thermal per year
Depth of wells for district heating: up to 1608 meters
Depth of wells for power plant: 3 kilometers
Heating provided to public buildings (school, kindergarten) and blocks of flats (total 65,000 m2)