Liquid Energy: Using Alaska's waterways to provide power.

• Author: Kvapil, Rachael

Water lit the muddy streets of Juneau City, as the gold mining town was known in 1893. That was the year Alaska Electric Light & Power (AEL&P) started providing service from a simple water wheel. Two decades later, the utility developed the Annex Creek, Salmon Creek, and Gold Creek hydropower plants, and they remain in service, generating 3.6 MW, 6.7 MW, and 1.6 MW, respectively.

Juneau is awash in hydropower, especially since the federal government build the Snettisham project in 1973. Water tapped from two lakes 28 miles southeast of Juneau drives 70 percent of Juneau's electricity, with a peak output of 78 MW. Another 20 percent comes from the Lake Dorothy facility on the east bank of Taku Inlet, generating up to 14 MW from the flow of water down a 5-foot diameter penstock. And that's just Phase 1; AEL&P has plans to double the output from Lake Dorothy, as demand warrants.

"Under the right circumstances, hydropower is a cost-effective and reliable source of carbon-free electricity," says Debbie Driscoll, AEL&P vice president and director of consumer affairs.

AEL&P isn't 100 percent carbon free; Driscoll notes that the utility burns diesel for standby generators during planned maintenance and short outages. However, AEL&P is unique in Alaska having such a large portion of its generation portfolio come from hydropower. Most Alaska utilities rely on a combination of natural gas, petroleum, and coal, plus a smattering of renewables in addition to hydropower. Juneau stands as a benchmark for others to measure up to.

Powering the Railbelt

A single powerhouse supplies 10 percent of the electricity for customers from the Kenai Peninsula to Fairbanks. The Bradley Lake Hydroelectric Project north of Homer, completed in 1991, is the largest hydroelectric facility in the state. The five Railbelt electric utilities--Chugach Electric Association, Golden Valley Electric Association, Homer Electric Association, Matanuska Electric Association, and Seward Electric System-share its 120 MW output. From 1995 to 2020, the Bradley Lake facility averaged 392,000 MWh annually at $0.04 per kWh, providing some of the lowest cost power to more than 550,000 Alaskans.

The Bradley Lake Hydroelectric Project took forty years of planning, fieldwork, licensing, construction, and agreements before generating any power. The US Army Corps of Engineers first studied Bradley Lake's potential in 1955, but it wasn't until 1962 that Congress authorized the project. Another...