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Exploiting an Enormous Energy Source

Harvesting geothermal energy from deep underground has great potential, but it faces significant obstacles.

Tuesday, August 07, 2007

By Kevin Bullis

It might not have been a great idea to try out a new approach to geothermal energy on a fault line. The AP reports that a utility in Switzerland that drilled wells to access hot rocks deep underground has had to shut down operations after it triggered earthquakes.

Ordinarily, geothermal energy relies on geologic formations that bring heat from deep below the earth near the surface. But research suggests that these geothermal sources barely scratch the surface of geothermal potential. (See this year's MIT report on the subject.) If engineers employ technology now used by the oil industry to drill down to hot rocks and then fracture the rocks to allow water to percolate through them, they could potentially access enough energy to supply thousands of times the United States' annual energy demand. (See also "Tapping Rocks for Power.")

Many energy companies are interested in the technology--but they're waiting to invest, wary that it might not prove practical. Ill-advised projects like the one in Switzerland won't reassure them. The engineers there expected rock slippage, the AP reports, but went ahead with the drilling anyway.

But engineered geothermal energy has another chance, according to the AP story. Now that the Swiss project is cooling off, another one, in Australia, in a more geologically stable area, has taken the lead. If that one proves successful, geothermal could be on its way to becoming a major source of world energy.

Tags: energy, geothermal

Comments

	Somebody is prevaricating dmm on 08/08/2007 at 2:33 PM
Posts: 149 Avg Rating:	Either there are more problems to be solved than the advocates are letting on, or else the various gov't organisations are running an energy scam (or global warming scam). Otherwise, why the "cool" reception? Rate this comment: (Reply)

	Re: Somebody is prevaricating DennisHarmon on 08/08/2007 at 5:57 PM
Posts: 1	In the 70's we, the Feds, did a pilot project and showed the viability. The EU, Japan and Australia all have projects going. (Common thread - no oil industry in power.) The system only requires standard oil drilling technology to reach bedrock, preferably granite. Then it is a matter of pumping water in closed loop to the rock which has been fractured to give greater surface area for heating. Fairly high capital investment. Minimal operating costs. Placement in any spot you can drill to rock. Rate this comment: (Reply)

	Geothermal Energy boylej on 08/13/2007 at 1:41 AM
Posts: 1	The city of Halifax, Nova Scotia is deploying the 1st geothermal (technically not correct) cold energy storage system in the world. On August 7, 2007 the local Council approved the $3.6 million project, awarding to a local engineering/technology firm. This project will harvest renewable cold energy in the winter (from the ocean) and store it in a borehole field for later use in the summer - without the use of heat pumps. The project is using a new type of heat exchanger which enables geo-cold storage. Cold energy is much more difficult to store in a usable form than hot energy. To see more about the project see http://www.halifax.ca/council/agendasc/cagenda.html We are only just starting to scratch the surface on the potential energy under our feet. There also exists a great potential to utilize geothermal storage in combination with wasted energy. When the advances in drilling technology are combined with our understanding of the complexities and nuances of geothermal energy flows an enormous resource will finally be utilized. A few bumps on the road have to be expected. Let's continue to explore, as long as the risk is managed and tolerable. Julian Boyle, P.Eng. Halifax Regional Municipality Rate this comment: (Reply)