Geothermal energy would produce 250,000 times the world’s annual energy needs with nearly zero impact on the environment – but the US typically says that the financial cost is too high.
Swiss and Australian engineering firms are currently racing to be the first to generate commercial power from “enhanced geothermal systems”, or EGS, a method of harnessing the earth’s inner heat using “hot rock wells” – shafts drilled deep into the planet’s crust.
Electricity would be generated by using this natural heat to boil water, which would then power a steam turbine. The energy potential is enormous – a study undertaken at the Massachusetts Institute of Technology said that if 40 percent of the heat under the United States could be tapped, it would meet demand 56,000 times over. The current project in Basel, Switzerland, expects to meet the electricity needs of 10,000 households, and heat 2,700 homes.
However, the Swiss project has been halted due to earth tremors, an unwelcome obstacle to this renewable energy source which could be crucial in the battle to reduce greenhouse gas emissions. The other major problem lies in the cost: hot rock wells need to be drilled several miles into the earth’s crust to reach the energy, and new wells would need to be created every few years as they cooled off. The MIT study estimated the cost of drilling a well at approximately $7 – 8 million, whereas the average cost of drilling an oil well in the U.S. in 2004 was $1.44 million, according to the U.S. Energy Information Administration.
With oil supplies dwindling and the effects of climate change becoming ever more apparent, many would say its time to invest some serious money into clean, green energy. However, Steve Chalk, deputy assistant secretary for renewable energy in the US, said the Department of Energy wouldn’t spend more money on hot rock technology beyond the $2 million that has already been allocated.