CREDIT: Wikimedia Commons/Heidi Soosalu
After accidentally drilling into a chamber of molten lava more than a mile underground in 2009, researchers in Iceland have now found a way to use the magma to create geothermal energy. This new method of producing geothermal energy could be especially valuable in Iceland, where geothermal power already makes up about two-thirds of the energy use and around 90 percent of homes are heated using geothermal.
Researchers from the Iceland Deep Drilling Project (IDDP) used the magma to generate high-pressure steam at temperatures over 450 degrees Celsius, beating the world record for hottest geothermal heat. According to the measured output, the magma generated about 36 megawatts of electricity.
Normal geothermal energy is generated by pumping water into heated ground, boiling it and then using the steam to generate electricity. This experiment in Iceland is the first time molten magma instead of solid rock has been used to create the steam.
“This could lead to a revolution in the energy efficiency of high-temperature geothermal projects in the future,” Wilfred Elders, professor emeritus of geology at the University of California, Riverside, who’s written about the Icelandic innovation, told The Conversation.
Geothermal power is both renewable and sustainable. According to the Geothermal Energy Association (GEA) “Geothermal plants emit about five percent of the carbon dioxide, one percent of the sulfur dioxide, and less than one percent of the nitrous oxide emitted by a coal-fired plant of equal size, and certain types of geothermal plants produce near-zero emissions.”
The global geothermal market was expected to reach 12,000 megawatts of operating capacity by the end of last year, according to the GEA.
As of 2012, there was about 3,187 megawatts of installed geothermal capacity in the United States. Last week, the U.S. Department of Energy announced $3 million to spur geothermal energy development, stating that “the U.S. Geological Survey estimates that 30 gigawatts of undiscovered hydrothermal energy potential exist untapped beneath the Earth’s surface.”
2013 saw some of the first Enhanced Geothermal Systems (EGS) demonstration projects. EGS inject water down into underground hot rocks via wells where it is then circulated and the heat is extracted to generate electricity. The water can then be recirculated.
Traditional geothermal energy production requires natural steam or hot water reservoirs in order to function. EGS uses water pumps to emulate the natural process and in doing so would allow for geothermal development at many more locations and for longer-lasting sites where natural underground resources can’t be depleted.