Monday, August 20, 2007

Swiss Geothermal Project Causes Earthquakes.

It has been confirmed by experts that the Deep Heat Mining project, located near the city of Basel to extract geothermal energy caused tremors of 3.3 on the Richter scale. The strategy involves the injection of considerable quantities of pressurised water into boreholes three miles deep where the temperature can reach 200 degrees C. The resulting superheated steam is brought back to the surface where it is used to provide steam with which to run an electricity-producing turbine. However, the project operators, Geopower Basel, have had to suspend its pumping of water into the hot rock layer since it has been discovered that this caused a series of earthquakes, some up to 10 miles distant.

An investigation is now underway to seek liability for everyone involved in the project, and possible criminal prosecutions, since it is claimed that those in charge were well aware that there was a risk of setting-off earthquakes. Basel is one of the areas in Switzerland most prone to seismic activity, and in 1356 the city was practically razed to the ground by a quake of 6.5 on the Richter scale. It has come to light that the officials of the project were warned that injecting water into the hot rock layer might trigger earthquakes, but according to an official response from the company it was not believed they would be felt at the surface.

Nuclear power has some string opposition in Switzerland and hence the Deep Heat Mining project curried favour as an environmentally-friendly and safe source of renewable energy. The Swiss government have partially financed the project which is intended to provide enough electricity for 10,000 homes and heat for another 2,700, but since the quakes there is far less faith in this approach. There have been similar projects in Australia, Japan and the U.S., but none of them has resulted in a similar triggering of earthquakes of the magnitude measured in Switzerland. Geology is complex and varies considerably from one region of the earth to another, and human "engineering" of natural forces must always be attended with some degree of risk. The Earth is a complex system, and tinkering with one aspect of it can influence others, sometimes catastrophically.

Related Reading.
(1) "Green Energy Project gives Swiss the shakes," by Bojan Pancevski, Sunday Telegraph August 11th.
(2) Deep Heat Mining and Earthquake Monitoring in Basel, Switzerland,"

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