Thermal energy to be researched in rock lab

An underground research laboratory to investigate the long-term use of geothermal energy has opened in the southern Swiss Alps.

The Federal Technical Institute of Zurich (ETHZ) says the facilities – situated in a disused access tunnel of the Matterhorn Gotthard railways in the Bedretto Valley – are a world first.

In cooperation with national and international partners, the ETHZ has installed seven additional seismic stations in and around the rock laboratory.

The Bedretto project wants to show that the construction of a heat exchanger that is sustainable over several decades can be planned and controlled with the aid of hydraulic stimulation processes, according to the promoters.

The experiments, to begin in July, will be carried out on larger scales (hundreds of meters) compared a previous project near the Grimsel Pass in the Alps. The Grimsel ISC project successfully carried out pressure fluid injection experiments in crystalline rock, according to the promoters.

“The larger scale implicates longer boreholes, which allow more realistic experiments to be carried out, applying different stimulation concepts,” said the Swiss Competence Center for Energy Research – Supply of Electricity.

“The Bedretto project addresses questions associated with (….) the sustainable utilization of heat exchanges in deep underground,” the Seismological Service of the ETHZ said.

The construction of the Bedretto lab is expected to cost about CHF20 million ($20 million) and allow researchers to carry out test inside the 5.2km-long tunnel for ten years.