Carbon capture, the technology widely deemed vital to saving the planet from a climate disaster – but frustratingly slow to gain traction – could have a friend in geothermal power.
For a few years, scientists have kicked around the idea of exploiting a possible synergy between the two technologies. Instead of pumping carbon captured from fossil-fuel-fired generating stations or industrial plants underground for storage, they’ve suggested taking advantage of CO2′s favorable properties and using it to replace water as the heat transfer mechanism in geothermal power plants, improving their efficiency and making geothermal power more widely viable geographically.
Well, that idea is back in the spotlight this month, with a twist: A team of scientists is proposing to use nitrogen, in addition to carbon dioxide and water, in some kind of network of “subsurface concentric rings of horizontal wells” to draw underground heat to the surface.
The researchers, from the Lawrence Livermore National Laboratory, Ohio State University and the University of Minnesota, said this past week that “in computer simulations, a 10-mile-wide system of concentric rings of horizontal wells situated about three miles below ground produced as much as half a gigawatt of electrical power – an amount comparable to a medium-sized coal-fired power plant – and more than 10 times bigger than the 38 megawatts produced by the average geothermal plant in the United States.”
earthtechling