Kansas regulators have reduced the amount Westar Energy can earn on transmission costs, which will save customers about $18 million over the next 12 months.

The Kansas Corporation Commission made the decision Tuesday. The commission said in a news release that the savings stem from a complaint it filed last year with the Federal Energy Regulatory Commission, alleging that Westar had over-earned on its transmission costs.

In March, FERC approved a settlement agreement between the KCC and Westar Energy. The reduction in transmission costs should save average households about $1.50 a month.