MIT report says geothermal power not to be ignored

In what its authors call the first study in 30 years to take a new look at geothermal energy, a new MIT-led group asserts that heat in the Earth's crust could supply a substantial portion of the electricity the United States will need in the future, probably at competitive prices and with minimal environmental impact.

An 18-member panel led by MIT prepared the 400-plus page study, released today, titled The Future of Geothermal Energy and sponsored by the U.S. Department of Energy.

Although geothermal energy is produced commercially today, and the United States is the world's biggest producer, according to the scientists, existing U.S. plants have focused on the high-grade geothermal systems primarily located in isolated regions of the west. This new study takes a more ambitious look at the resource, its authors say, and evaluates its potential for much larger-scale deployment.

"The answer to the world's energy needs may have been under our feet all this time," said Jefferson Tester, professor of chemical engineering at the MIT Laboratory for Energy and the Environment.

Even in the most promising areas, drilling must reach depths of 5,000 feet or more in the west, and much deeper in the eastern United States.

Panel member Brian Anderson, an assistant professor at West Virginia University, noted that the drilling and reservoir technologies used to mine heat have many similarities to those used for extracting oil and gas. As a result, the geothermal industry today is well connected technically to two industry giants in the energy arena, oil and gas producers and electric power generators, and possible synergies should be explored, he suggested.

Government-funded research into geothermal was active in the 1970s and early 1980s. As oil prices declined in the mid-1980s, enthusiasm for alternative energy sources waned, and funding for research into renewable energy and energy efficiency (including geothermal) was greatly reduced, making it difficult for geothermal technology to advance, the authors noted.

In its report, the panel recommends that:

• More detailed and site-specific assessments of the U.S. geothermal energy resource should be conducted
• Field trials running three to five years at several sites should be done to demonstrate commercial-scale engineered geothermal systems
• The shallow, extra-hot, high-grade deposits in the west should be explored and tested first
• Other geothermal resources such as co-produced hot water associated with oil and gas production and geopressured resources should also be pursued as short-term options
• On a longer time scale, deeper, lower-grade geothermal deposits should be explored and tested
• Local and national policies should be enacted that encourage geothermal development
• A multiyear research program exploring subsurface science and geothermal drilling and energy conversion should be started, backed by constant analysis of results

The report may be downloaded in its entirety here.