A Seattle-based company is preparing to try and tap a dormant volcano in Oregon for geothermal energy this month.
Engineers from AltaRock Energy have been given the go-ahead by the US Bureau of Land Management to begin injecting water into a network of cracks 3 kilometers underground, at the site of the Newberry volcano in Oregon.
Geothermal power projects normally use naturally occurring hot water in the Earth, but much geothermal energy is also stored in impermeable hot rocks. The method used in this type of project is to fracture the rocks with pressurised water, to increase the permeability of the rocks enough to use them for geothermal power generation.
The Newberry volcano site is being used because, obviously, the rocks are hotter at a shallower depth in volcanic areas. It is hoped that this will increase efficiency, as hot rocks are often very deep in non-volcanic areas. If successful, it is thought that the cost-efficiency of a project such as this could rival fossil fuels.
Apparently the go-ahead for the geothermal project was given after independent studies had shown that the project did not have a high risk of causing earthquakes in the area, or contaminating groundwater. It is expected that testing of the project will be finished by 2014.