Barriers to Adoption of Geothermal Power Generation
Only a few countries use geothermal resources as a major source of electricity production –Iceland, El Salvador, and the Philippines all use geothermal for more than 25% of total electricity generation within those countries. New Zealand is the next (but distant) largest at 10%. Where hydrothermal resources are easy to access they have often been utilized. Trouble is, there just aren’t that many Old Faithfuls in the world.
EGS represents the most significant potential for geothermal electricity production, but other than a few small military or pilot projects, the systems have not really caught on commercially. One of the big reasons is cost – like many low-carbon electricity technologies, EGS is inexpensive to run but very costly to build. Drilling geothermal wells is much more expensive than drilling conventional oil or gas wells, so electricity prices would probably need to increase by 25% or more (relative to current averages) to make EGS a financially viable technology.
Perhaps a more serious challenge for EGS is “induced seismicity,” which is a fancy term for causing earthquakes. EGS wells that were drilled below Basel, Switzerland caused over 10,000 small tremors (less than 3.5 on the Richter scale) within just a few days following the start of the hydraulic fracturing process. In Oregon, a test EGS well is being monitored for induced seismic activity – you can see some neat real-time earthquake data at Induced Seismicity (U.S. Department of Energy: Energy Efficiency and Renewable Energy.
Induced seismicity occurs whenever hydraulic fracturing (related to EGS or developing a natural gas well) takes place, but in most cases, the earthquakes are so small they are not felt. However, if the hydraulic fracturing occurs near pre-existing faults (which are often not visible at the surface), then larger earthquakes can and do occur, and some of these are strong enough to cause minor damage to buildings nearby.