From 4,000m deep to 6,000 households: geothermal electricity in Haute-Sorne (Switzerland)
Overview
A pilot project in Switzerland, the Haute-Sorne Deep Geothermal Project is using innovative methods to provide clean and affordable electricity to 6,000 households in the Jura municipality of Haute-Sorne.
After the site selection, in 2012, the project has undergone several steps to ensure the feasibility and replicability of the experience. Through a cutting-edge method called the Multi-Stage Stimulation Concept, the risk of induced seismicity is significantly reduced. In the first semester of 2025, the exploration phase of the project was conducted by Geo-Energie Jura SA (GEJ) with very positive results, opening doors for future projects of this kind in Switzerland.
Following these optimistic results, the Haute-Sorne project is expected to provide 20 GWh/year by the end of the decade, enough to power 6,000 households without emitting CO2. Besides sustainability, the project will ensure that energy costs are significantly reduced for these households: experience from comparable projects suggests that levelised electricity generation costs will come at under 15 cts/kWh, less than half of the average cost in Switzerland (32 cts/kWh).
Technical Details
Through the Multi-Stage Stimulation Concept, a geothermal reservoir is created in solid rock without the need for natural hot water sources. As a precaution against seismic risk, this system stimulates the rock in several smaller stages, which also increases the efficiency of the reservoir and the project’s profitability. During the exploration phase in 2025, drilling went 4,000m deep and the temperature was superior to 140ºC. Based on the existing data, the project is expected to provide over 20 GWh/year, powering 6,000 households and saving 3,200 tons of CO2 emissions per year.
Milestones:
2012-2013: Site selection and project development
2015: Cantonal approval for special land use plan
2018-2019: Federal Supreme Court decision and approval of federal exploration funding
2020-2021: Technical proof of concept demonstrated at the Bedretto rock laboratory
2022: Signing of the second agreement with the Canton of Jura
2024: First drilling operation reaching a depth of 4,000 meters successfully completed
2029: Planned commissioning
Summary:
Drilling Depth: 4,000-5,000 meters
Drilling Temperature: >140ºC
Geothermal Capacity: Max. 5MW electric (approved) 2-3 MW electric (expected output)
Geothermal Production: >20 GWh/year (at 2.5 MW, approximately 6,000 households)
CO2 Emissions Saved: >3,200 tons/year
Investment Cost: > CHF 120 million
Sources:
Contact information: Olivier Zingg – o.zingg@geo-energie.ch