Geothermal power production is often neglected in national projections of evolving US energy supply. This may be due to the widespread perception that the sources for this power generation are too few in the nation. This has led to an obstruction in developing new technologies in this field. In spite of this, "Ormat Technologies, Inc. (NYSE: "ORA") announces the successful co-production of geothermal power at a producing oil well. This project marks the first of its kind by providing on site fuel free power that will increase the productivity and possibly extend the longevity of existing U.S. oil fields".
"The project, a Cooperative Research and Development Agreement (CRADA) at the DOE’s Rocky Mountain Oil Test Center (RMOTC) near Casper, Wyoming, is designed to validate the feasibility of using proven recovered energy-generation technology to produce electricity using hot water produced from oil and gas wells, according to Ormat" (JPT October 2008).
Ormat employs a technology which is called Organic Rankine Cycle (ORC) power generation system (figure 1) commercial electricity. It is similar to a 250 KW factory integrated unit that has been producing electricity from 210 º F geothermal water at an Austrian resort since 2001, according to the company. Conventional geothermal fluid extraction involves mining operation in which the fluid once passed through the turbine is vented to the atmosphere. But through this technology the water will exit from ORC at a lower temperature, will be reinjected to the reservoir (figure 2). This avoids the depletion of the reservoir.
Ormat is investigating the expansion of this ORC technology into other oil fields. "The company quotes an estimate by Senator Mike Enzi of Wyoming that in the US alone, oil fields could provide an additional 5,000 MW of electricity through this technology. In addition to providing power to oil fields, Ormat plans to feed this generated electricity into the grid, essentially putting oil and gas companies in the geothermal business" (JPT October 2008).
Field test like this will kick start a productive research in the field of Geothermal Energy and ultimately will contribute to the nation's energy need through a comparatively cleaner process. If this is really a promising energy source, the new government should spend more research funds on harnessing this which needs comparatively less capital money.
1) Co-production of geothermal power at oil wells