Credit: AltaRock Energy
2012 could be the year that Enhanced Geothermal System (EGS) technology takes off and enters the public consciousness. And to highlight this, Altarock, the Seattle based geothermal energy developer, has recently announced plans to undertake field tests by 2012 on a volcanic site in Oregon, with expected support from the government department of energy and Google, whilst similar developments in Europe and Australia are at more advanced stages. Even China has outlined its plans to use EGS technology to provide 10 -15% of its total power generation by 2050.
It is an ambitious technology that exploits the huge untapped energy potential in deep impermeable rock, or hot dry rock systems. Basically, water is drilled deep into impermeable rock to open up spores where the steam / hot water is piped back up to create energy. It bypasses the limitations of traditional geothermal technologies which are restricted to particularly conducive areas near the earth’s surfaces. It is more carbon neutral, can be used on virtually any land surface, creates a new economy or jobs and is renewable in the sense that the water it uses is interred in a continual closed loop.
In fact, the energy forecast is so high that in the U.S. 500,000 MW (potentially) could be utilized, which is around half of the electric power generation capacity currently used. In the other ‘hotbed’ of ESG research, Australia, Geodynamics is currently in the drilling stage of a huge 500 MW site at the Cooper Basin site. Furthermore, EGS technology is already commercially viable at Landau in Germany and at the Soultz-sous-Forêts site in France which is already partially energizing Paris Orly Airport.
However, there are still hurdles to be overcome and they are chiefly economic. In the U.S., AltaRock Chief Technology Officer Susan Petty says that the price incentives are just not competitive. On the technical side, reservoir connection and lifetime issues could be problems: fears of induced seismicity cause local communities to be wary. There is also the issue of the necessary high level public and private investment to support energy developer’s claims of the bankability of EGS.
Overall, the betting is on EGS reaching maturity in the next few years with rising R&D successes and commercially viable plants coming into fruition. It is certainly a technology to keep an eye on.