Wednesday, November 7, 2012

Harnessing geothermal energy while reducing CO2 can be done

The CO2 plume geothermal system (CPG) is brand new and very promising technology to harness geothermal energy. The main difference between this technology and the conventional one is that it doesn't use extracted hot water to drive turbines in process of generating electricity but instead relies on high-pressured carbon dioxide (CO2).

Apparently CO2 is much better medium than hot water because CO2 travels much easier through porous rock than this is the case with water. The easy travel ensures that significantly more heat is extracted compared to conventional geothermal systems, and thus should result in increased efficiency of these systems as compared to conventional ones.

The higher efficiency is not the only benefit of this technology. Another important advantage is a positive impact on climate change because harnessing geothermal energy with this new technology also means preventing CO2 from reaching the atmosphere by sequestering it deep underground. This also means that this technology could offset the high cost of capturing the CO2 in a coal fired power plants, making carbon capturing process more economically viable. There have been even proposals about using CO2 geothermal pumps to create underground energy storage to solve the problem of intermittency that is widely present with solar and wind energy projects.

The experiments and simulations done by researchers at the University of Minnesota, Department of Earth Sciences, have showed that CPG systems would be viable geothermal energy sources for electricity power generation for decades to come, even in regions with low geothermal temperatures and heat flow rates. CPG systems are also expected to significantly reduce the risk of triggering earthquakes as compared to conventional systems.

The currently used technologies allow geothermal energy harnessing to be commercially viable only in areas at plate boundaries or at places where the crust is thin enough to let the heat through. The CPG technology is looking very promising to be used in regions where conventional geothermal electricity production is not feasible enough to attract investments.

Harnessing geothermal energy while reducing atmospheric CO2 certainly sounds like an ideal clean energy solution. Hopefully, this new technology will build on its excellent potential and spread geothermal energy harnessing to many new areas, all over the world.