Geothermal energy has long been considered a viable resource in Alaska. It is better distributed and less environmentally costly than fossil fuels, but it is yet to be exploited. The rise of oil prices, technological advances in geothermal resource exploitation, and a changing demand profile have moved geothermal to the front burner in Alaska. This paper reivews two predominant geothermal resource regimes in the state of Alaska: 1) Interior/Seward Peninsula Springs. These are low to moderate temperature systems with surface expression as hot springs. They are commonly associated with plutons of late Mesozoic to early Tertiary age and occur in a broad east-west swath from the Yukon Territory of Canada to the Seward Peninsula. 2) Aleutian Volcanic Arc. These are high temperature hydrothermal systems with expression as hot springs and fumarole fields along the Alaska Peninsula and the Aleutian Islands. They are associated with active volcanoes and subduction zone-related faulting. Installation of a 60 MWe plant on a similar volcano on the Kamchatka Peninsula, Russia has demonstrated the benefits of developing Aleutian-type geothermal systems.
Affordable, reliable energy is essential for the economic progress and long-term survival of communities in Alaska. Nowhere else in the United States is energy such a life-or-death issue or are so many communities off-grid. The result is that the state government must subsidize energy production in bush communities. Ironically, Alaska is rich in fossil fuels, but resources are commonly located hundreds of miles over roadless terrain from potential Alaskan users. Moreover, because most refining occurs outside of the state, the end user in Alaska usually pays more for petroleum products than non-Alaskan consumers.
Geothermal resources in Alaska remain unexploited despite the proven existence of high-potential reservoirs. This is due to a combination of factors: cheap fossil fuel resources, high development risk, and scattered energy demand centers. Each of these barriers to development is weakening.
The development of Alaska?s geothermal resources is more economically feasible than it was in the past. The rising cost of oil concurrent with recent technological advances, such as enhanced binary systems and the development of efficient, modular power generation capabilities, have significantly reduced the risk of developing geothermal power plants. The energy demand profile of Alaska is changing as well. Some of the communities potentially impacted by geothermal development are of more than trivial interest to the nation as a whole. For example, Dutch Harbor in the Aleutians accounts for more than half of US seafood production. Rising energy costs and uncertain fuel supplies have a deep effect on Alaska?s remote areas, where commercial activities are already hampered by current prices.