Geothermal energy: new EGS project in the USA
A newly announced project will test an enhanced geothermal system in the volcanic area of Newberry, aimed at producing energy from deep rocks that are heated by the magma chamber
A new enhanced geothermal (EGS - Enhanced Geothermal Systems) project was launched in the USA.
The EGS technology aims to produce energy from special hot spots in the Earth's crust, that is, from abnormal geothermal situations which cause dry rocks to be heated deep under the ground (even at very high temperatures) by close magmatic systems.
The new project, proposed by a specifically established consortium between AltaRock Energy and Davenport Newberry, is included in the Geothermal Technologies Program and has received a grant of $21.5 million (about EUR 17 million) from the Department of Energy (DOE), in addition to investments amounting to approximately $22.4 million from the consortium that proposed the project.
Testing will take place near the volcanic area of Newberry, thirty kilometres away from the city of Bend (Oregon). This site was chosen because, though the Newberry volcano is inactive, its magmatic chamber is quite close to the surface (less than 5 km).
The EGS technology consists in drilling a number of well bores in order to reach hot spots deep under the ground, where a more or less extended subsurface fracture system is created, where hot water from the surface circulates. Water is then heated by contact with the rock’s high temperature and can be pumped back to the surface and used in facilities that resemble those powered by conventional geothermal fluids.
This technique is still undergoing a testing phase, but it is considered promising for the future. According to a study conducted by the Massachusetts Institute of Technology in 2007, it can be assumed that - after 2050 - EGS plants will meet 10% of US electricity consumption. In the meantime, a lot is still to be achieved regarding plant innovation and design, as well as the need to use new materials that prove to be reliable when facing the environmentally difficult situations concerning hot spots.
(June 2010)
