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Oulun Energia explores the potential of geothermal heat

29.12.2021 / Last updated 00:00

Oulun Energia is involved in a geothermal consortium that will implement a drilling project in Tampere. The project explores drilling for geothermal heat in Finnish soil using the hydraulic shock technique and the single-well principle. The project involves 15 energy companies from different cities in Finland, from Rovaniemi to Vantaa and from Vaasa to Joensuu. The drilling technology comes from South Korea, from HanJin D&B.

“The strength of the single-well operating model is its low environmental impact. The bedrock will not be fractured and waste water will not be generated in a closed cycle,” says Jukka Joronen, director of Tampereen Sähkölaitos, who is leading the project.

The Kaupunkilämpö consortium, formed by several energy companies, will first test the hydraulic shock technique at Tarastenjärvi in Tampere, near Tammervoima's waste-to-energy power plant. The plan is to first drill a well three kilometres deep. The drilling started today.

“If the drilling is successful and there is heat, we will discuss the future,” Joronen promises.

According to calculations, it is warm enough at a depth of about seven kilometres to make geothermal heat a significant new source of district heat. Hot water can be produced for the district heating network using many different methods. For a district heating customer, geothermal heating is an interesting and worry-free addition to the selection, as the customer can utilise the heat of the earth without any technical changes in the heat distribution room.

The benefits of geothermal heat include being emission-free, renewable, adjustable, and independent from the seasons. It does not entail transport costs, and it has a ready-made customer base in the cities of large district heating networks.

Oulun Energia's goal is climate-friendly district heat

Oulun Energia is actively researching and testing the use of new energy sources in district heating production. Oulun Energia already produces carbon-neutral district heat using renewable energy and by utilising the wasted heat from shops. “The district heating network serves as a platform for making the fastest change to climate-friendly heating energy in cities,” says Pertti Vanhala, business director at Oulun Energia.

Geothermal heat is being studied as one possible alternative to add to the production options of climate-friendly district heat. “This may be one part of the solution to replace the Toppila 2 power plant unit, which will be decommissioned in the next decade, with heat production that is not entirely based on incineration,” Vanhala says.

Through this experiment, Oulun Energia will receive valuable information about the possibilities of geothermal heat. “We want to make the change to the district heating system responsibly and safely. If the results of the Tampere test well are promising, geothermal heat in Oulu will also heat our homes in the future,” Vanhala says.


The project involves Alva group, Etelä-Suomen Energia, Kangasalan Lämpö, Kuopion Energia, Lahti Energia, Lappeenrannan Energia, Leppäkoski, Arctic Circle Water and Energy Ltd, Oulun Energia, Pori Energia, Porvoon Energia, Savon Voima, Tampereen Sähkölaitos, Vaasan Sähkö, and Vantaan Energia.

Additional information:

Pertti Vanhala, Oulun Energia
Jukka Joronen, Tampereen Sähkölaitos