CHARLESTON, W.Va. -- Appalachian Power plans to convert a portion of its plant in Russell County, Va., to natural gas, and has asked the West Virginia Public Service Commission to approve the conversion and allow the company to recover costs associated with it. APCO asked the PSC for permission to change two of the three generating units at the Clinch River Plant from coal-fired to gas-fired. The project will cost $65 million. If approved, that cost will be reflected in a customer rate increase. "For more than 50 years three generating units at the Clinch River Plant have served Appalachian's customers well," Charles Patton, Appalachian Power's president and chief operating officer, said in a written statement. "However, they are not equipped to meet recently approved and anticipated environmental requirements and must shut down."Converting two of the Clinch units to natural gas and retiring the third is the best alternative to meet energy needs, taking into account economic and environmental considerations and diversifying the company's power plant fleet," he said. If approved, the conversion would cost a residential customer using about 1,000 kilowatt-hours each month less than 50 cents for the month, an AEP spokeswoman said. That cost on consumers will vary depending on the cost of fuel and other factors that affect customers' bills, spokeswoman Jeri Matheney said. If the PSC approves APCO's request for converting the plant, it will then request a rate increase, Matheney said.The project also will involve extending a natural gas pipeline to serve the plant. Appalachian Power wants approval for its request by February in order to meet construction deadlines in 2015 and 2016. The natural gas units are expected to be working in 2016.