Geothermal without the Earthquakes

Technology Review
May 17, 2011

A startup in Connecticut says it has a way to improve the reach of enhanced geothermal energy, without the financial or geological risks associated with such projects.

Enhanced geothermal systems (EGS) represents a promising source of clean power generation in geographies that lack the ideal combination of underground heat, water, and rock permeability needed for conventional geothermal. But with EGS, developers typically have to engineer the conditions they require, and this involves fracturing solid rock by pumping fluids into wells at high pressure, an approach that has raised concerns about the potential to trigger earthquakes and contaminate aquifers.

The problem, called "induced seismicity," led to the cancellation in 2009 of a project in Basel, Switzerland, after the high-pressure fracturing of rock around the well caused hundreds of seismic events, some large enough to damage property. In North America, EGS developer AltaRock Energy has been caught up in a similar controversy.

To read more click here...