New York, NY [RenewableEnergyAccess.com] Alcoa announced that it has made a significant contribution to a research and development program in Iceland, the Iceland Deep Drilling Project (IDDP) consortium.
The consortium will collaborate on a deep drilling pilot project that will investigate the economic feasibility of producing energy and useful chemicals from geothermal systems at “supercritical conditions,” i.e. natural systems where underground water becomes super-heated by close proximity to almost molten rocks.
According to the company, supercritical (high-temperature) geothermal systems could potentially produce up to ten times more electricity than the geothermal wells typically in service around the world today.
The IDDP consortium is composed of three leading Icelandic power companies: Hitaveita Sudurnesja Ltd.; Landsvirkjun; and Orkuveita Reykjavikur; together with Orkustofnun (National Energy Authority) and Alcoa.
The production of energy from supercritical fluids requires drilling to depths of 4 to 5 km (13,000-16,000 ft) in order to reach fluid temperatures of 400-600°C (750-1100°F). Today, typical geothermal wells are about 2 km deep (8,000 ft) and produce steam at about 300°C (570°F)—a rate sufficient to generate about 5 megawatts (MW) of electricity. It is estimated that producing steam from a well penetrating a reservoir at or above 450°C (840°F) and at a rate of 0.67 cubic meters (24 cubic feet) per second could generate 40-50 MW of electricity.
The first wells will be drilled in 2008 at Krafla in north-east Iceland and tested the following year. Two new wells, 4 km deep, will then be drilled at Hengill and Reykjanes geothermal fields during 2009-2010 and subsequently deepened. The consortium expects pilot plant testing to be completed in 2015.