Duke sets 6.2 percent increase to residential electric rates

That's based on a 6.2 percent increase in the utility company's residential base rate. That increase will go to 7.3 percent after four years.

The basic customer charge, which customers pay before they use any electricity, will increase from $11.13 to $14 per month.

The North Carolina Utilities Commission still has to finalize the rates, but it approved the methodology Duke Energy Progress used to set them last month, following a lengthy rate case.

The company had asked for future costs to be included in its rate increase request, as well as costs already incurred. The commission told it to keep track of coal ash costs and return to the commission later.

Duke faces hundreds of millions of dollars in costs a year because of state laws requiring it to clean up and close toxic coal ash basins in the wake of a 2014 ash spill in the Dan River.

Hearings in a separate rate case for Duke Energy Progress' sister company, Duke Energy Carolinas, are set to begin Monday. Duke Energy Carolinas serves most of the western half of the state, including Durham, and the company initially asked for more than $600 million a year in increased revenue, which would work out to an increase of about 13 percent.

That request has come down some, due to a settlement the company struck this week with the commission's Public Staff, which represents ratepayers in cases before the Utilities Commission, but there are a number of unsettled issues to hash out in hearings before the commission.

Duke Energy Carolinas has also asked for an increase to cover coal ash cleanup costs.