CHEYENNE, Wyo. (AP) — The PacifiCorp coal-fired power plant in southwest Wyoming will remain fully operational for at least another year.

The Portland, Oregon-based utility company had announced last year that the Naughton plant near Kemmerer would close one of its three power-generating units at the end of 2017 as a result of declining electricity demands and the costs of meeting federal pollution requirements.

PacifiCorp spokesman David Eskelsen says the unit closure was based on state of Wyoming environmental requirements that resulted from the state trying to meet federal regional haze requirements initiated under the Obama administration.

However, Eskelsen says the federal government was giving the company until the end of 2018 to make any changes to the unit. He says PacifiCorp will continue to reassess switching the unit to natural gas.