With an estimated cost of US$440M, the expansion project would add a further 125MW capacity at Holtwood, more than doubling its existing capacity of 108MW.

PPL resubmitted the Holtwood expansion application to FERC in April 2009 after withdrawing the original application in December 2008, citing economic conditions. In refiling the application, PPL said incentives in the federal stimulus package could make the project feasible again by offsetting the factors that caused the company to withdraw its original application.

Additional benefits of the project are improved passage for migratory fish along the Susquehanna River and its tributaries, and improved recreational opportunities.

PPL has selected Walsh Construction of Chicago as the general contractor for the project, which is expected to create more than 200 construction jobs. Some pre-construction work has begun, but construction is expected to fully start in the first quarter of 2010. Voith Hydro will supply the turbines generators for the project.

FERC’s approval of the Holtwood project – which also includes an extension of the existing operating license to August 2030 – comes just weeks after PPL’s official start of redevelopment at its Rainbow hydroelectric plant near Great Falls, Mont. The Montana project, with an estimated cost of $230M, will increase the power output by 70% and improve fish passage when the project is completed in 2012.