12 the Wrangell Mountains and Aleutian Volcanic Arc are most likely to have electricity production capability as they are situated above active, volcanic subduction zones. There has been limited geothermal research in recent years, and much of the research referenced today is from the 1970s and 1980s, suggesting further work is required. However, the active volcanoes in these areas make them desirable power plant sites for electricity from geothermal energy. Wind Energy in Alaska Wind currents, a product of solar heat, geographical variation, and the Earth’s spin, rotate blades attached to a central tower, which, in turn, runs a generator to produce electricity. High altitudes and coastal areas present greater development opportunity because they experience higher sustained wind speeds that yield more energy. Although total costs generally are higher for offshore compared to onshore development, offshore turbines can produce more energy and may be preferred. Land-based turbines are more difficult to ship and construct in Alaska with its limited road system, while offshore turbines can be shipped using barges. Variation in wind speeds, regardless of location, makes it less than 100% reliable, but wind still could provide an offset for nonrenewable energy. Today, wind energy constitutes just 2% of Alaska’s energy profile, about 64 MW of capacity, with significant room to grow (WINDExchange, 2021). Existing wind energy infrastructure is concentrated in a few large projects along the coast. The largest, Eva Creek, is located between Anchorage and Fairbanks and has 12 turbines, with a hub height of 80 m, generating a total capacity of 25 MW. The Fire Island project, off the coast of Anchorage, contains 11 similarly sized turbines, with a capacity of 18 MW. Other projects located at Nome and Kotzebue have a lower capacity with more, but smaller, turbines, with hub heights between 30 m and 50 m (Hoen et al., 2021). These operations point to areas where wind energy infrastructure can improve and grow. New wind energy potential also can be evaluated using observed wind velocities at turbine hub heights. The National Renewable Energy Laboratory created a series of maps that detail wind velocities at various altitudes and can be used to draw conclusions about potential. Wind speeds at 50 m are sufficient for community-scale energy production along most of the Alaskan coast and the mountain ranges in the interior of the state. The largest continuous area of community-scale generation potential is in the southwest surrounding Bethel. Generation of utility-scale electricity requires a hub height of 80 m or higher and is concentrated in the same regions as energy potential at 50 m. Overall, the western coast, the southwestern corner surrounding Bethel, and the Aleutian Islands have promising development potential (WINDExchange, 2021). Tidal Energy in Alaska Tidal energy is produced using the water currents associated with ocean tides but is not yet widely used or developed. There are two ways to harness tidal energy: a semipermeable barrage built across estuaries with a high tidal range and a turbine system placed offshore, especially in narrow or converging topographies, to harness strong currents. A significant benefit of tidal energy is its reliability. The lunar and solar gravitational pull that creates Earth’s tides is constant; as a result, tides are predictable. However, there are a few drawbacks to this form of energy, including high upfront costs, potential inconsistencies in energy production, and impact on the ecosystem. Jim Jager, manager of the Port of Alaska in Anchorage, says smaller tidal generators could be placed strategically along a coastline, so that each observes high and low tides at different times. This solution could mitigate the large-scale impact on the ecosystem and could aid in consistent energy production. He also believes a significant tidal project in Cook Inlet would be accompanied by a significant storage system to regulate output (personal communication, January 26, 2022). In certain coastal areas of Alaska, like Cook Inlet, where Anchorage is located, the low and high tides have greater than a 30-ft difference with accompanying high currents, which creates ideal tidal energy conditions. The National Renewable Energy Laboratory has begun research in Cook Inlet for its favorable tidal energy conditions. Thus far, research has shown an estimated capacity of 6 GW to 18 GW of theoretical tidal power in the East Foreland area of the inlet, which is also an ideal location due to its proximity to the electrical grid.
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