By Meg Cichon | RenewableEnergyWorld.com
A major challenge for the geothermal industry is reducing the risk of its exploration and drilling phase – there is a 40-60 percent chance that each $5-7 million well is ultimately deemed unproductive. But that statistic may soon change. In what many in the industry are calling a game-changer, the nation’s first enhanced geothermal system (EGS) to supply electricity to the grid came online last week. ORMAT’s Desert Peak 2 project is producing an additional 1.2 megawatts (MW) of power to its existing nearby power plant.
ORMAT started the project back in 2002 and has spent the past decade researching with U.S. Department of Energy (DOE) how to make an in-field EGS project work. When hot rocks below the surface cannot be permeated with conventional geothermal technology, EGS technology is used to pump highly pressurized fluid into existing fractures of the hot rock in order to create a flowing reservoir.
At Desert Peak, ORMAT had previously drilled a well that only allowed an injection rate of about four gallons per minute, which was then deemed unproductive and abandoned. After performing years of research that included creating seismicity protocol, the EGS procedure was a success, and the well now has an injection rate of up to 1,600 gallons per minute — it was essentially connected to the existing reservoir at the site.
