The approval, issued Thursday, clears the way for LG&E to start building a $583 million plant. LG&E and Kentucky Utilities estimated a $110 million purchase price for the Bluegrass Generation plant.
The commission disagreed with environmental interests, who said the two companies could meet power needs through a combination of wind power and more aggressive demand reduction efforts.
Kentucky Utilities has about 506,000 electric customers in 77 counties across Kentucky. Louisville Gas & Electric has about 401,000 electric customers in nine counties in the Louisville area.
LG&E's 312,000 natural gas customers are not affected by this case.