WWU Geologist Pete Stelling Researching Geothermal Power Sources in Alaska’s Aleutian Islands

Akutan, a small island in Alaska’s Aleutian chain, needs 4.2 million gallons of diesel fuel a year to keep the lights on and the houses warm for its 125 year-round inhabitants and its major industry, a seafood-processing plant – at a high cost both literally and in terms of environmental damage.

Western Washington University assistant professor of Geology Pete Stelling is researching how to turn the island’s volcanic core into a geothermal power source that could not only cut the needed amount of imported fuel into a fraction of its current level but transform the quality of life for its inhabitants.

Central to the landscape of the island is the 4,275-foot volcano, Mount Akutan, which last erupted in 1992. Beneath its surface, pockets of water are being superheated by the volcano’s magma; utilizing this superheated water and its steam to generate electricity could free the island from its need to import so much fuel, said Stelling.

“The majority of electrical generation today surrounds boiling water and using the steam to drive a turbine, which spins a generator and makes electricity. The fuel – coal, oil, or natural gas, for instance – is used to boil that water,” he said. “Geothermal sources skip the need for a fuel and go to the superheated water right at its source to make the electricity, and this could happen at places like Akutan to make them far more energy independent.”

The perfect geothermal source, according to Stelling, occurs when the superheated water, over time, dissolves the surrounding rock and turns it into clay that acts as a cap, keeping the water and steam from escaping or losing pressure. Iceland, for example, is rife with these types of sources, one reason why the island nation is 80 percent powered by geothermal energy.

Stelling is researching the viability of secondary sources that are far more common but less attractive for development. In most cases, these “second tier” geothermal sources were once under a glacier; the immense pressure of the glacier’s weight has pushed the hot water far closer to the surface, in most cases eroding the clay cap that has kept it under such high pressure.

“The low-hanging fruit has very often been picked,” he said. “But these sources could be incredibly important, because they are far more numerous. What we are looking to find is just how powerful these secondary sources are.”

On Akutan, for example, harnessing the geothermal power from the sites that Stelling and his peers on the research team have researched could provide electricity to light and power the appliances in every home on the island as well as support its major industry, a seafood-processing plant that has up to 1200 employees during peak season. In addition, the heat from the geothermal sources could provide ample warm air to operate greenhouses, allowing islanders to grow fruits and vegetables year-round – providing a scare commodity in a place that that sits at the end of a long ferry run from the mainland, as well as local jobs.

Stelling is working on two parallel projects.  The first is to continue working with the Akutan exploration team to continue moving forward to harness the resource for the benefit of the island’s population in a way that is far more economically viable and far less environmentally damaging than the current diesel-based methods, which currently comes all the way from Tacoma, Washington.  The second is to use the Akutan resource to understand just how efficient these secondary geothermal sources are and apply these lessons worldwide. 

“These secondary geothermal sites have such incredible potential,” Stelling said. “The more we learn about them, the more they can be used to improve the lives of these folks and make them more energy independent.”

Stelling will return to the island this summer to continue his work; he plans for his next research locations to be in similarly volcanic areas such as Chile and Colombia. The Akutan geothermal exploration research has been funded by the City of Akutan, the Alaska Energy Authority, and the U.S. Dept. of Energy. Stelling’s work on secondary resources has been funded by Western Washington University with potential funding from the National Science Foundation.  The Akutan exploration team working on the island includes members from the Geothermal Research Group (GRG) of Palm Desert, California; RMA Consulting Group of Anchorage, Alaska; and the City of Akutan.

For more information on his research, contact Pete Stelling, Western Washington University assistant professor of Geology, at (360) 650-4095 or pete.stelling@wwu.edu.

Wednesday, February 25, 2015 - 3:54pm