Projects

Located 25 miles southeast of Wrangell, Tyee Lake was constructed in 1981 and provides power to both Wrangell and Petersburg.  It uses a lake tap to draw water from Tyee Lake.  The project has a 22.5 MW capacity with average annual generation of 48,198 megawatt-hours (MWh), although it has been running at over 61,000 MWh the last two years.  The project is significantly underutilized, with annual project capability at approximately 128,000 MWh, exceeding the loads of the three cities combined. 

Swan Lake is located on Revillagigedo Island about 22 miles northeast of Ketchikan.  The 22.5 MW project includes a pipeline, powerhouse, and tunnel and generates an average of 71,244 MWh per year, with a maximum capability of 80,000 MWh.  All project output is used by Ketchikan. 

An intertie between the two projects is under construction and will be 57 miles in length.  The $115 million project, funded almost entirely by grants, will be complete by 2010.  It will allow for greater utilization of Tyee and Swan Lake power and will interconnect the three utilities, adding reliability, with additional Tyee Lake energy to serve Ketchikan. 

Both projects were put into operation in 2004 and have historical availability factors of approximately 95% and 97% for Tyee and Swan, respectively.  Each plant has at least two turbines, so for repairs and routine maintenance, the agency can still operate the plant at some level.