TOPEKA, Kan. (AP) – The largest electric utility in Kansas has agreed to refund $10 million to its customers and decrease its rates slightly to settle a complaint filed by state regulators with the federal government.

Topeka-based Westar Energy and the Kansas Corporation Commission announced the settlement Wednesday. It would a resolve a complaint filed by the KCC last year with the Federal Energy Regulatory Commission.

The Kansas commission had alleged that Westar was charging unjustly high transmission rates. The federal commission must approve the settlement.

Under the settlement, Westar will make the refunds and decrease its rates by about $8 million a year. The company estimates that most residential customers would save 40 cents a month.

But Westar is also asking the Kansas commission to boost other rates by $152 million.