Duke plans to build natural gas-fired plant in Asheville. Source: Duke Energy.Duke Energy Progress says it will shut down its 376 megawatt (MW) coal-fired Asheville power plant in North Carolina. It plans to build a 650 MW combined-cycle, natural gas-fired power plant on the site.

The decision was made due to the high cost of retrofitting the coal plant, which was built in 1964, to conform to the new disposal regulations the state adopted in the wake of the Dan River coal-ash spill in February 2014. At current prices for natural gas, Duke says it expects the new facility to cost about 35% less to operate than the existing coal plant.

Duke will also build a solar farm on the site, although it will be significantly smaller than the gas facility. In addition, it will build a new substation in Campobello, S.C., to connect with the new gas-fired power plant by a 40-mile, 230-kilovolt transmission line.

The entire project is expected to cost $1.1 billion, reports the Charlotte Business Journal.