SACRAMENTO, Calif. — Advanced geological mapping and subsurface drilling tools must still be developed in order for geothermal power to become a more prominent source of renewable energy, experts said at the National Geothermal Summit.
In a breakout session at the summit on Wednesday, Aug. 8, a panel of government and private-sector geothermal experts discussed the value that additional 3-D modeling, geophysical surveys to indicate hot water flow below ground, and other research and development work could have on the future of geothermal exploration.
James Faulds, director of the Nevada Bureau of Mines and Geology, said that like oil and gas deposits, about two-thirds of the geothermal energy sources remain hidden, with no surface expression. Advanced technologies for fossil fuels has been developed, but similar advancements for geothermal have lagged behind.
In addition, Faulds added that often you’ll have a geothermal well in production, but then another site just a few hundred feet away may be hot, but dry. Those risks are a major impediment for developing geothermal systems.
“We need a better understanding why certain wells are productive and why others are not,” Faulds said. “Fundamentally we need better conceptual models of these geothermal systems to figure out where to drill and reduce the risk.”
“Some of this can be funded by industry, but some of the broader studies probably need to be funded by government entities,” Faulds added.
The U.S. Department of Energy was represented by Hildigunnur Thorsteinsson, team lead of the U.S. DOE Hydrothermal and Resource Confirmation. She agreed with Faulds that in comparison with oil and gas production, there’s a lack of high-performance tools and temperature devices for geothermal exploration.
Thorsteinsson pointed out that there are a variety of technical pathways to overcome, organized by the DOE into categories like advancements in non-invasive geophysics, invasive geophysics, geology and structure, remote sensing, geo-chemistry and cross-cutting, seismic gravity tools.
Joe Iovenitti, vice president of resource for Alta Rock Energy Inc., added that short-term goals should be established to find ways to lower the cost of drilling and to establish further techniques for boreholes and wells.
In the long term, Iovenitti believed geothermal exploration would be dependent on data integration. He suggested the government purchase private data sets related to geoscience and make that data available to companies that are interested in geothermal pursuits. Iovenitti said that would help correlate where to drill and what drilling applications will work in a certain area.
“There’s definitely a technological challenge here that we can address,” Thorsteinsson said regarding the U.S. government’s ability to help companies interested in geothermal drilling. “And it’s an opportunity for the department to put up funding opportunities and make some progress.”
Thorsteinsson revealed that the U.S. DOE is pushing forward with funding projects. She said there are more than 30 federal R&D efforts under way. One in particular deals with percussive and encapsulated drilling techniques that have particles in the drilling buds that make tiny explosions down in a hole to help break up rock.
Those projects that meet technical milestones will receive funding for a second phase starting in 2013, Thorsteinsson added.