Pocahontas County on geothermal hot spot
The locomotives at Cass Scenic Railroad are a perfect example of the dependability of coal-steam technology that's been in use for more than 200 years. The same basic technology is used to produce more than two trillion kilowatt hours of electricity every year in the U.S.
But researchers at a Texas university concluded that steam alone, heated by rocks beneath the surface of eastern West Virginia, could produce more electricity than all the existing plants in West Virginia.
On October 15, Southern Methodist University (SMU) researchers announced the findings of a two-year study to map geothermalﾠ resources in the U.S., which showed surprisingly hot rocks more than three miles beneath the surface of eastern West Virginia - making the area the best spot in the eastern U.S. for a developing type of geothermal power production.
"A large area in eastern West Virginia has been found to have elevated heat flow and upper crustal temperatures compared to the rest of the eastern United States," the study reads. "The high heat flow has been recognized based on interpretation of bottom-hole temperature (BHT) data from oil and gas drilling in the area."
The study revealed temperatures of almost 350 degrees Fahrenheit, five kilometers (16,404 feet) deep, over an area 68 miles wide by 105 miles long.
"The temperatures are high enough to make this the most attractive area for Geothermal Energy development in the eastern one-third of the country and the heat in place is sufficient to support large scale development of Enhanced Geothermal Systems," the report states.ﾠ
The researchers concluded West Virginia's geothermal generation potential is 18,890 megawatts, more electricity than is currently produced in the state from all sources (16,350 megawatts).ﾠ
Enhanced geothermal system (EGS) technology differs from conventional geothermal energy, which taps heat from volcanic activity near the surface. EGS involves drilling into hot rock strata deep underground, fracturing to create a reservoir, and pumping water through the strata to produce steam, which is collected from multiple wells. The steam pressure is used to drive turbines and produce electricity.
AltaRock Energy, headquartered in Sausalito, California, is one of the few U.S. companies working to develop EGS. AltaRock president Susan Petty said other countries have taken the lead in EGS.
"The U.S. is definitely lagging behind," she said. "We haven't done any new geothermal research in this area, in the enhanced geothermal, since the original, first hot dry rock project was done in New Mexico at Fenton Hill back in the 1980s. Since then, all the research has moved to Japan and the U.K., to Europe and to Australia. We're just really missing the boat on this."
Potter Drilling is a Redwood City, California, company working to improve deep-drilling technology for EGS.ﾠ Potter's VP for business development, Mark Hankowski, agrees the U.S. has fallen behind in EGS development.
"The Australians are currently the leaders inﾠ EGS commercial development," he said. "They have the most commercial companies out there trying to develop it and to actually make a profit on it. I think there's 12 public companies - the leading company is a company called Geodynamics. They received a $90 million grant from the Australian government to continue their project. I'd say Australia is ahead of the U.S. in development of EGS."
Hankowski said he expects U.S. funding to average $30-50 million annually for both EGS and conventional geothermal research.
Petty said development of a working EGS plant on the East Coast is a vital next step for the geothermal industry.
"We think that it's crucial to move geothermal out of the Western states, where it's typically found, and we're working on the technology that will hopefully make that more economic," she said. "Right now, conventional geothermal is cheaper than coal power in the West. When you move into the advanced technologies that would be needed to get the deeper resources that you can anticipate finding in West Virginia, it's still pretty expensive. We're working on technology development that we hope will make that less expensive."
"One of the things for the geothermal industry that is very important is to see development of geothermal resources on the East Coast," he said. "If you look at federal funding for geothermal, one of the reasons it's so small is because, right now, it's limited to resources in the Western U.S. If you see resources starting to open up on the East Coast, you'll see much more interest from the federal government in trying to develop this.
"The discovery of geothermal resources in West Virginia is extremely important for the future of this technology. We're excited about it and we're hoping that, in a very short period of time, you will see some development of the resource on the East Coast."
A 2006 Massachusetts Institute of Technology (MIT) - led study urged a federal commitment to EGS development.
"Because prototype commercial-scale EGS will take a few years to develop and field-test, the time for action is now," the report states. "Supporting the EGS program now will move us along the learning curve to a point where the design and engineering of well-connected EGS reservoir systems is technically reliable and reproducible."
Petty said construction of the first EGS plant in West Virginia would take years and be expensive.
"It would probably take, in a new area where there's never been geothermal before, four to five years to get a project up and running," she said. "That's just because the permitting process and the ability to explain the project to regulators and to get funding for it - because it hasn't been done in West Virginia - it would take more time. It would cost, probably - the first project in West Virginia - about $6,500 per installed kilowatt. Pretty expensive. If you're doing a 10 megawatt project, you're looking at a $65 million project."
However, a small-scale prototype plant could be expanded, according to Petty
"That's the nice thing about this type of geothermal is that it's scaled," she said. "You could start with a small project to show that it would all work, figure out your economics and then expand it outward without a whole lot of trouble. You don't have to build a single giant power plant. You can do it a little more modularly and it doesn't impact the cost that much."
Despite the high start-up cost of a new, prototype plant in West Virginia, Petty said the long-term operational costs would be low.
"Geothermal plants have no fuel cost, obviously, so you don't have that, but you do have O&M costs - you do have to pay people salaries and keep things maintained," she said. "That runs anywhere from a penny per kilowatt hour to two-and-a-half cents per kilowatt hour, depending on what kind of equipment you have."
Geothermal energy is relatively clean because it does not burn fuel and creates no air pollution. But, EGS involves fracturing of deep rock formations to create an underground hot water reservoir, similar to hydrofracking for natural gas production. Undoubtedly, questions will arise about the potential pollution of underground aquifers.
Hankowski said there is little, if any, risk to water supplies.
"Predominantly, you're doing this much deeper than where you find the water table, so you don't find contamination of the water table like you would with the fracking for gas," he said.
The U.S. has increased support of geothermal research since the release of the MIT study in 2006, said Hankowski, who estimated the government will provide an average of $30-50 million annually for all geothermal research, not just EGS.
In addition to continued funding, Petty said the government needs to modify regulations to allow funding for EGS drilling.
"The federal government has restrictions and they aren't restrictions under the law, but they are restrictions under the regulations that implement the law, that don't allow them to fund drilling the geothermal wells for this kind of thing," she said. "I'm not real sure how you do geothermal without drilling and I think the government needs to review what they're doing with this and think about it and find a way to fund drilling."
AltaRock and partner geothermal company Davenport-Newberry received $21.45 million in economic stimulus funds from the Department of Energy this year for an EGS project at Newberry National Volcanic Monument in Oregon. The two companies are investing an additional $22.4 million in the project. The team plans to develop an EGS reservoir in a high-temperature, low-permeability rock formation, demonstrate stimulation techniques to maximize fluid flow and heat extraction, and culminate with the conceptual design of a commercial-scale wellfield and power plant.
The Obama administration requested $55 million in the FY2011 budget for development of geothermal energy - a 25 percent increase -ﾠ and $300 million for the Advanced Research Projects Agency - Energy,ﾠ for which developers of enhanced geothermal energy will be able to compete.
The SMU study was funded by a $489,521 grant from Google.org, which also provided $4 million to Potter Drilling and $6.25 million to AltaRock Energy for development of EGS technology. For more information, see www.google.org/egs.