San Antonio’s CPS Energy on Monday announced it would mothball by 2018—15 years earlier than planned—its 871-MW coal-fired J.T. Deely Power Plant—instead of spending an estimated $3 billion on pollution controls to comply with anticipated environmental regulations. The nation’s largest municipal utility expects to replace the plant’s generation through conservation and future renewable sources.

The Deely plant’s two units were completed in 1977 and 1978. They were built to diversify the utility’s portfolio, which relied solely on natural gas at the time, said CPS Energy CEO Doyle Beneby on Monday. The utility may also look into buying an existing gas-fired plant in Texas to help replace output from the Deely units, Beneby said.

The utility is looking to increase the percentage of renewable resources in its generation portfolio to 20%—or 1,500 MW—and to have 65% of its generation resources as low- or no-carbon emitting by 2020.

The utility will also mothball three natural gas–fired power units over the winter, a recent filing with the Electric Reliability Council of Texas (ERCOT) shows. The three units at the V.H. Braunig plant, built between 1966 and 1970, total 847 MW. CPS hopes to close the plants for five to seven months starting Oct. 1.

The announcement of the Deely plant’s pending retirement was made as Mayor Julian Castro said that five clean-energy technology firms would either relocate to San Antonio or invest in the city over the next several years.

Beneby added that the five companies would partner with CPS Energy to curb energy use by improving efficiency. “At CPS Energy, we have the enviable position of having safe, affordable nuclear power and a new coal plant with the best available emissions control technology,” he said. “These resources allow us to support the development of clean technologies to generate electricity, while maintaining rates among the lowest in the nation.”

Sources: POWERnews, CPS Energy