Enhanced geothermal system
An enhanced geothermal system (EGS) is a geothermal energy system that can make electrical energy when natural underground water is not there.[1]
For a long time, geothermal energy could only be produced where there were hot rocks, underground water, and cracks in rocks all together in one area. These areas may need underground water or a network of fractures in their rocks or both.
Heat can now be got outside normal geothermal areas like active plate boundaries. It can be got in less active areas like the western United States.
The heat is got by artificially pushing water down into hotter rocks. This can create new fractures through the rock in addition to expanding the existing fractures. That is why the new technique is called "fracking".
Enhanced Geothermal System Media
Enhanced geothermal system: 1 Reservoir, 2 Pump house, 3 Heat exchanger, 4 Turbine hall, 5 Production well, 6 Injection well, 7 Hot water to district heating, 8 Porous sediments, 9 Observation well, 10 Crystalline bedrock
Map of 64 EGS projects around the world
Geothermal power technologies.
Map of current and planned superhot rock energy projects
References
- ↑ Pierce, Brenda (2010-02-16). "Geothermal Energy Resources" (PowerPoint). National Association of Regulatory Utility Commissioners (NARUC).