KETCHIKAN (KDN) — The Swan Lake hydroelectric facility expansion that was completed in 2017 reached full capacity for the first time in July, according to a September press release from the office of Sen. Bert Stedman, R-Sitka.
After the expansion — which provides an additional 15 feet of water storage — was completed, drought conditions prevented the facility from reaching the newly expanded capacity.
Stedman stated in the press release that the expansion “ensures that we can store more hydropower and use it during the fluctuating rainy seasons. This is just a part of a larger ongoing expansion, and we are currently reviewing other hydropotentials to increase storage generation in the future.”
The need to expand the Swan Lake facility on Revillagigedo Island was identified as a priority in the Southeast Alaska Integrated Resource plan developed in 2012. The expansion created 25% to 30% more storage, going from about 86,000 acre-feet of water to 111,800 acre-feet, according to the release.
The expansion also is expected to provide up to 12,000 MWh of additional energy annually, which equates to 800,000 gallons of diesel fuel, according to the Southeast Alaska Power Agency, the regional generation and transmission entity that provides wholesale power to member utilities.
In the first year of the project, an additional $1.1 million in diesel generation to Ketchikan was offset.
Another benefit to the expansion project was that in addition to savings in diesel expenditures, about 17.9 million pounds of carbon dioxide were prevented from being emitted into the atmosphere, according to the press release.
The expansion project was funded partially through a $3.9 million direct appropriation from the State of Alaska, and SEAPA sold bonds for the remaining balance, according to the announcement.
The Alaska Congressional delegation supported the project, prompting the passage of the related Swan Lake Boundary Adjustment Act. According to the press release, “numerous” state agencies and the U.S. Forest Service also worked collaboratively to finish the project.
The intertie between Swan Lake hydroelectric facility to the Tyee Lake hydroelectric facility also has benefitted from the project, allowing greater utilization of the energy generation capability of the Tyee facility and better reliability throughout the system.
“This is a great example of maximizing the value of an existing hydroelectric asset without the need for additional transmission or powerhouse infrastructure,” SEAPA CEO Trey Acteson said in the prepared statement.
The Swan Lake facility powers Ketchikan, and the Tyee Lake facility sends power to Wrangell and Petersburg.