When a team of scientists drilling near an Icelandic volcano hit magma in 2009, they had to abandon their planned experiments on geothermal energy. But the mishap could point the way to an alternative source of geothermal power.
"Because we drilled into magma, this borehole could now be a really high-quality geothermal well," said Peter Schiffman, professor of geology at 51³Ô¹ÏºÚÁÏ Davis and a member of the research team along with fellow 51³Ô¹ÏºÚÁÏ Davis geology professor Robert Zierenberg and 51³Ô¹ÏºÚÁÏ Davis graduate student Naomi Marks. The project was led by Wilfred Elders, a geology professor at 51³Ô¹ÏºÚÁÏ Riverside.
A paper describing geological results from the well was published this month in the journal Geology.
When tested, the magma well produced dry steam at 750 degrees Fahrenheit (400 degrees Celsius). The team estimated that this steam could generate up to 25 megawatts of electricity -- enough to power 25,000 to 30,000 homes.
That compares to 5 to 8 megawatts produced by a typical geothermal well, Elders said. Iceland already gets about one-third of its electricity and almost all of its home heating from geothermal sources.
The team was drilling into the Krafla caldera as part of the Iceland Deep Drilling Project, an industry-government consortium, to test whether "supercritical" water -- very hot water under very high pressure -- could be exploited as a source of power.
They planned to drill to 15,000 feet -- more than two miles deep-- but at 6,900 feet, magma (molten rock from deep within the Earth) flowed into the well, forcing them to stop.
The composition of magma from the borehole is also providing insight into how magmas form beneath Iceland, Schiffman said.
The team included researchers from two Icelandic power companies, HS Orka hf and Landsvirkjun Power; Iceland GeoSurvey; the U.S. Geological Survey; Stanford University; New Mexico Institute of Mining and Technology; and the University of Oregon, Eugene; as well as 51³Ô¹ÏºÚÁÏ Davis and 51³Ô¹ÏºÚÁÏ Riverside.
The work was funded by the National Science Foundation and the International Continental Scientific Drilling Program.
Media Resources
Andy Fell, Research news (emphasis: biological and physical sciences, and engineering), 530-752-4533, ahfell@ucdavis.edu
Peter Schiffmann, Geology, (530) 752-3669, pschiffmann@ucdavis.edu