Marine Energy

Wind, wave, tidal resources could help Alaska meet future energy needs

Wind, wave, tidal resources could help Alaska meet future energy needs
Cook Inlet, Alaska (Photo by Levi Kilcher/NREL)

Researchers with the National Renewable Energy Laboratory determined that offshore wind makes sense for decarbonizing energy production and building energy security and independence when it comes to ocean renewable energy production in Alaska’s Outer Continental Shelf (OCS).

Their report, “Feasibility Study for Renewable Energy Technologies in Alaska Offshore Waters,” was conducted for the Bureau of Ocean Energy Management (BOEM) to evaluate the feasibility of ocean energy projects in federal waters, including wind, wave and tidal resources. The study area also included state waters outside of BOEM’s jurisdiction to allow broader consideration of tidal and wave energy that often have the best resources closer to shore.

“Offshore wind development could be a viable option in Alaska waters, particularly in areas closest to Alaska’s population centers. It is also important to remember that all ocean energy development efforts must incorporate just and equitable approaches for energy transitions,” said Elise DeGeorge, a senior project leader at NREL and a co-author of the report, which examines ocean renewable energy opportunities in Alaska in the next 10 to 20 years.

“Alaska is rich in natural resources, and that includes offshore renewable energy resources,” said Givey Kochanowski, director of BOEM’s Alaska OCS Region. “Near Anchorage, Cook Inlet alone has significant wind- and tidal-energy potential. We are happy to work with any interested party to help explore opportunities for tapping those vast resources.”

The 131-page report, which was written by 11 researchers working in eight areas, recommends the Alaska office of BOEM assess interest in demonstrating the potential for ocean energy through a pilot study or other critical research initiatives.

Alaska’s OCS holds the potential to generate 3,800 GW of electricity from wind, wave and tidal resources. But because of constraints such as the long distances to customers and potential conflicts with other ocean users and wildlife, only a small fraction of these resources can practically be developed. Alaska derives about 30% of its electricity from renewable sources, primarily hydropower. The rest comes from fossil fuels, but the cost is expensive in rural villages because of the reliance on diesel generation and having to transport the fuel.

The researchers examined the ocean-based resources available for producing energy and conducted case studies of hypothetical utility-scale projects. In addition, they examined the production of clean hydrogen as a longer-term solution to serving end users and creating an external market from the ocean renewable energy produced.

Most Alaskans live in the Railbelt area, a large section of south-central Alaska that sits north of Cook Inlet and stretches from Anchorage to Fairbanks. The vast majority of electricity is generated in this same area, primarily from natural gas. Outside of the region, more than 200 remote grids serve rural villages.

The researchers calculated the levelized cost of electricity (LCOE) generated by offshore wind and tides. “Wave energy could also be a viable option in certain regions, but we didn’t calculate LCOE as time to commercialization may extend beyond the report’s planning period,” DeGeorge said.

In the case studies, the researchers considered 1-GW offshore wind scenarios, for floating and fixed-bottom turbines, and a 65-MW array of tidal devices. The LCOE projections for offshore wind in locations further from Alaska’s Railbelt included the clean hydrogen component as one potential external market to make development costs more feasible. The lowest LCOE was for a fixed-bottom turbine in Lower Cook Inlet, at $83/MWh.

The tides in Cook Inlet rise and fall by as much as 35 feet, but the LCOE for a tidal array there was still higher than for offshore wind, at $280/MWh. NREL researchers are working with the Alaska Center for Energy and Power on finalizing a road map for developing tidal energy projects in Cook Inlet.

The NREL report recommends BOEM remain involved with the existing working groups focused on tidal energy and clean hydrogen.

NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy LLC.