Geothermal developer EnergeÔ has announced the results of a geothermal well drilled into the Malm formation at the Vinzel site in Switzerland. Water flow from the well was revealed to be exceptionally high, but the temperature is below expectations. With these results, the developer has taken a step back to assess potential technical solutions to fully exploit this resource,
The “Vinzel-1 Malm” is a sidetrack well drilled into the Malm limestone layers after the original well was found to have non-commercial pressure. Drilling of the sidetrack well started in April 2023, targeting both the Malm layer and the Saint-Cergue Fault.
The well was drilled to a vertical depth of 1524 meters and had a total length of 1820 meters. A natural artesian flow was measured and stabilized at an impressive 150 liters per second. Water flowed from a feed zone between 800 and 1210 meters depth and had a wellhead pressure of 20 bars. However, the maximum measured temperature was only 33 degrees Celsius – significantly lower than the expected 50 degrees Celsius.
In view of these results, EnergeÔ has decided to stop operations at the Vinzel site. The well was secured using a double safety barrier consisting of a mechanical plug 750 meters deep, itself supported by heavy mud, and a surface flange.
EnergeÔ nevertheless remains dedicated to the in-depth analysis of the data collected. The company will now assess the situation and explore potential technologies that can help utilize the geothermal resource and its exceptional pressure. The company also wishes to actively dialogue with the Canton of Vaud and the Swiss Federal Office of Energy (SFOE) in order to study the various possibilities for the future of the Vinzel site.
