Geothermal heat has the potential to fulfill 25% of demand for domestic heating in the Netherlands, Dutch state energy company EBN has said.

The EBN is calling for new housing to be realised in places where geothermal heat is accessible, and so relieve the pressure on existing systems and speed up the shift to cleaner sources of energy.

The process involves using hot water retrieved at a depth of several kilometres, which is then pumped back underground again once it has cooled.

Deep drilling has been taking place in eight places in the Netherlands, while measuring equipment has been installed in tens of thousands of locations to gauge the suitability of the geology.

The first results are promising, EBN told RTL Nieuws. Under government policy, seven million homes are supposed to swap their gas supply to another energy source before 2050 and geothermal heat can potentially heat 2.6 million of these homes, the agency says.

Drilling in Amsterdam has just been concluded and the news is good, EBN operations manager Gitta Zaalberg told the broadcaster.

“We did not know what to expect,” she said. “The temperature of the water we pumped up turned out to be over 80°, hot enough to heat a large number of houses in the capital, possibly as early as 2031.

“We are facing a huge challenge and we want to be less dependent on gas from abroad. Thermal heat is a great alternative option,” Zaalberg said.

The test drilling is being monitored to avoid the risk of earthquakes by the mining state supervisory body (SodM), which has warned that the technique, although deemed safe, comes with some risks.

“We have learnt lessons from the Groningen gas extractions and the damage and misery they caused,” SodM director Boukje van der Lecq-Meijssen said. “You have to listen to the locals, and make sure they have faith in the safety and reliability of geothermal heat extraction.”