Fracking, a controversial process used to inject highly pressurized liquids into rock to extract natural gas, has now come to a volcano near you. Sort of. An alternative energy company called AltaRock Energy is using hydroshearing, a technique similar to hydraulic fracking, to pump water deep underground near Newberry Volcano with hopes of returning not natural gas, but steam that could be used to “fuel” a power plant. AltaRock is hoping its project will serve as an example for a method of clean energy known as enhanced geothermal systems (EGS). EGS could provide for a tremendous amount of the country’s energy needs—perhaps as much as 100 gigawatts in 50 years, according to a 2007 study by the Massachusetts Institute of Technology.
Comparisons to fracking are easy to make, but upon deeper research, a little insulting to AltaRock. While fracking involves hazardous chemicals hidden under the guise of trade secrets, AltaRock has fully disclosed the chemicals it is using, most which have been used for years in groundwater remediation and other geothermal projects. The depths involved are below any useful aquifers, and the company is going to great lengths to protect the surrounding groundwater, using a “vertical mile of repeatedly-tested steel casing and cement that isolates fluid injected into or produced from the geothermal well from the groundwater,” according to the company’s project blog (http://blog.newberrygeothermal.com). Finally, the pressures involved are far lower than those used in natural gas fracking. The project has received a go-ahead from the U.S. Department of Energy (DOE)—as well as half the funds for its $44-million price tag—and the Bureau of Land Management (BLM) has determined that it will cause no significant impact to the environment.
The main problem behind EGS is typically its large installation expense—that and its propensity to cause earthquakes when installed improperly. The DOE reported that sites in Switzerland, Germany, and France have experienced “moderate seismicity due to EGS activities.” One site in Switzerland was recently shut down because of this.
However, the chances of a large quake are deemed miniscule enough to offset the benefits.
Still, the DOE reports that Geysers in northern California, a geothermal project that produces more than 700 megawatts of electricity, has caused countless microseismic events and one earthquake of magnitude 4.6. These events have all been measured at less than the size of a magnitude 5 quake that would be deemed dangerous. Given that the project at Newberry is taking place on a much smaller scale, there’s probably not too much to worry about. Perhaps oil and other fossil fuel companies are the only ones who should be concerned about AltaRock’s vision for the future.
by Jen Matteis