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Volcanic power possible for Unalaska? Community in Alaska’s Aleutian Islands takes another look at harnessing thermal energy from nearby Makushin Volcano Alan Bailey Petroleum News Staff Writer
Living right next door to a volcano may seem an uncomfortable idea but sometimes can prove to be an advantage: the city of Unalaska, in Alaska’s Aleutian Islands just 14 miles or so from the active Makushin Volcano, is looking to use that volcano as a prolific source of electrical power and heat.
Iceland America Energy LLC, a subsidiary of Enex Corp., has acquired geothermal rights on the slopes of the volcano in hopes of harnessing a hot water source that the U.S. Department of Energy found back in 1982. Enex is an Icelandic company that specializes in geothermal exploration and production
DOE drilled a 1,900-foot hole in the side of the volcano and found a source of water at a temperature of 390 degrees Fahrenheit, Unalaska City Manager Chris Hladick told Petroleum News. Flow testing by DOE of the geothermal water showed that after about 30 days the temperature only dropped 2 degrees F, Hladick said. Modeling indicated the capability of producing 1.6 million pounds of steam per hour from the geothermal source. Visit to Iceland Early this November six city officials and some Native representatives visited Iceland to see how that island nation harnesses geothermal energy. As well as the availability of geothermal energy Hladick sees some obvious similarities between Iceland and Unalaska: both territories are dependent on fishing, share similar climates and have similar landscapes.
“What they do in Iceland is pretty amazing — what they have been able to accomplish,” Hladick said. “90 percent of their homes are heated with this hot water.”
But ideas for harnessing the geothermal energy for Unalaska have proved uneconomic in the past. Hladick said that there have been several proposals at different times, with the most recent proposal coming in the early 1990s.
“The project was estimated at about $94 million, $97 million,” Hladick said. “It wasn’t feasible at that time.” Enex proposal In the spring of 2005 Enex proposed to the Unalaska city council an investigation into the potential for using geothermal energy. Enex then investigated the situation and delivered a report to the city.
“That report reconfirmed that there is a resource available,” Hladick said. “They have estimated the resource as capable of producing 50 megawatts of electricity.”
Enex proposed the construction of a power plant at the volcano, using what is known as a binary organic Rankine cycle, Hladick said. Geothermal fluids from the volcano would enter a heat exchanger, to transfer heat to a form of alcohol called isopene, Hladick said. The alcohol has a lower flash point, or boiling point, than water and can act as a working fluid that drives the power plant turbines at relatively low temperatures.
After leaving the heat exchanger the geothermal fluids would heat fresh water for piping to the town to heat buildings. The thermal output from this type of system normally equates to about four times the electrical output, Hladick said.
“So it would be 200 megawatts of thermal heat possibility,” he said.
The hot water system would require 12 to 14 miles of insulated pipeline from the volcano to an insulated storage tank in town. The need for this pipeline to cross four miles of water, up to 260 feet deep, would present a major challenge, Hladick said. Four power producers The fact that there are four different power producers in town also presents a significant complication for the project. Each of the three Unalaska fish processing plants generates its own power and the city also has a power plant. The extent to which the different electricity producers participate in the project will greatly impact the economics of the geothermal energy.
“Our peak right now is about 7 megawatts for the city, and the city owns and operates the utility here,” Hladick said. “ … The peak (for everyone) is about 21 megawatts.”
Peak demand occurs twice a year when fish processing occurs. But geothermal energy works best with steady electrical loads.
“Geothermal would be used to supply a base load of power and then the peaks would be handled by diesel (generators),” Hladick said. Feasibility Enex is about to send cost estimates for the proposed geothermal system to the Unalaska city council. The council will then compare these estimated costs with pricing from other projects and will plug the costs into financial models to assess possible power rates from the system.
“At this point we’re in feasibility, analyzing whether or not this would be feasible, what the costs would be, talking to the fish processors about who’s going to participate and who doesn’t,” Hladick said.
If the project turns out to be feasible, Hladick thinks that the geothermal energy might in the future spin off some industrial activity that would stimulate the Unalaska economy. He described how Iceland has attracted an aluminum smelting industry that uses the cheap electrical power from geothermal power plants. Hladick things that hydrogen generation might be a possibility for Unalaska.
“If you have cheap power you can make hydrogen,” he said.
Meantime Unalaska needs to determine the economic feasibility of the Enex proposal and settle issues such as who would own the plant and take the business risks.
“If everything looks good … it will be several months, I’m guessing, of discussions with the fish processors and how you would dispatch it, who would run it, leading up to negotiations then with Iceland America Energy for a long term power sales agreement,” Hladick said.
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