Werner Siemens Foundation of Switzerland has committed 10 million Swiss francs in funding a Deep Geothermal Energy initiative, via a donation made to the ETH Zurich Foundation.
“We must now make every effort to tackle the fundamental research for this form of geothermal energy quickly if we want it to deliver tangible benefits in ten to twenty years’ time,” says Ralph Eichler, President of ETH Zurich.
Geothermal power is widely considered an untapped sustainable energy source because the heat extraction is small compared with the heat content in the earth's crust. This energy is pollution-free, regular and controllable.
The Swiss federal government’s energy strategy aims to increasingly harness renewable energy sources for heat and electricity production, and geothermal energy R&D forms part of this strategy.
ETH Zurich is set to play a part in this strategy by supplying fundamental knowledge, innovative processes and the skilled personnel needed to construct and operate facilities of this kind in the future, Eichler points out.
As of yet, no Swiss household gets its electricity from a deep geothermal power station, according to the two companies.
Deep geothermal power is harnessed when water is pumped down to crystalline bedrocks, heated, and then brought back to the surface to turn turbines for electricity, although the technology is still in its infancy in Switzerland and internationally.
While more commonly used geothermal energy comes from a depth of 150-200 m where temperatures are around 6-8°C, it is possible to drill much further down to 10,000 m where temperatures can reach 374°C and the water is highly pressurised.
In harnessing this energy source, many challenges need to be overcome before it can realise its huge potential. Challenges include developing suitable drilling techniques and the artificial fissuring of the bedrock. Deeper drilling presents challenges due to the high temperatures, steel becomes brittle and materials such as plastic and electronics will weaken or melt. Research into geology of the bedrock from which the heat is to be extracted is also necessary.
ETH Zurich’s current focus is to determine the potential of deep geothermal energy in specific terms and make reliable forecasts for the future, according to the company.
There is a “need for accurate research into innovative exploration techniques, monitoring instruments and the possible risks involved in deep geothermal energy,” says Domenico Giardini, Professor of Seismology and Geodynamics and ETH Zurich’s delegate for deep geothermal energy.
This may be especially important in light of the earth tremors which were felt in an area where geothermal development was taking place in Basel, Switzerland, in December 2006. The deep geothermal borehole was subsequently abandoned.