CHEYENNE -- Thousands of power customers in northeast Wyoming may soon see their electric bill go up for the first time in 15 years.

Black Hills Power, which serves about 2,700 customers in Weston County, has asked the Wyoming Public Service Commission to raise its electric rates starting this spring to help pay for a new power plant being built near Gillette.

Under the proposed rate increase, a typical residential customer in Weston County who uses 600 kilowatt hours of electricity per month would pay an additional $19.44 per month, the utility company stated in a media release. Rates would also go up for commercial and industrial customers depending on their power usage plan.

The rate hike would bring in an estimated $3.8 million, which Black Hills Power communications manager Julie Schad said will be put towards building the $247 million, 100-megawatt Wygen-III coal-fired power plant, as well as other expenses.

If approved, the new rates would take effect when the Wygen-III plant comes online, which is expected to be April 1.

This is the first time since 1995 that Black Hills Power has raised its electric rates in Wyoming, Schad said. In that time, she said, the utility has seen residential electricity use in its Wyoming coverage area rise 33 percent.

"(A rate increase) is something that we have to do," Schad said. "I mean, our customers expect electricity, and in order to continue serving them with reliable, safe electric service, we have to have generation for future use."

Contact capital bureau reporter Jeremy Pelzer at 307-632-1244 or jeremy.pelzer@trib.com