The Aardwarmte Alton project in the municipality of Dijk en Waard in the Netherlands has been put on pause by developer HVC Groep after the well test results were deemed disappointing. With this, the drilling rig at the site will be dismantled while the company evaluates possible scenarios to continue with the project.

“Geothermal heat from Alton is currently not delivering the results we had expected. Because we believe in the potential of geothermal heat, we will investigate in the coming period what is possible to improve the results of this well,” said Laurien Smies, Director of Heat at HVC.

This does not change our conviction that geothermal heat can make an important contribution to the heat transition. Especially now that we want to become less dependent on gas from abroad and the climate challenge remains significant, sustainable heat sources are urgently needed.”

Drilling for the geothermal heating project in the Alton area of Heerhugowaard started in September 2026. Prior to this, the project had been approved by shareholders with a costs of approximately EUR 75 million for drilling and construction. The original plan was to drill four geothermal wells to depths of 2400 meters, targeting thermal waters at 85 ºC. Heat from Aardwarmte Alton was intended to be supplied to houses and other buildings connected to HVC’s existing network in Heerhugowaard.

Although drilling reached the target reservoir at 2.5 kilometers, well testing indicated that the productivity of the well was less than expected. This was a surprising result for the developer, as eight geothermal wells had been drilled with successful results targeting the same geological layer, albeit about 20 kilometers away.

The disappointing results of geothermal drilling have no effect on the current heat supply, as the network is current served by a biomass plant and waste-to-energy plant by HVC.

For now, the wells will be sealed and the rigs will be dismantled as the developer evaluates whether drilling more wells on the site is technically and commercially feasible. Several scenarios will be considered, including the possibility of a restart.

Prior to Alton, HVC had successfully drilled a geothermal doublet at Wippolderlaan, discharging thermal waters at 85 ºC. This follows work done at Trias Westland, Aardwarmte Maasdijk, and Aardwarmte Polanen. HVC currently operates 18 geothermal wells supplying approximately 15 MWth of sustainable heat, comparable to the heat consumption of a major Dutch city.