Minnesota utility regulators have granted CenterPoint Energy slightly more than half of the rate increase the company had requested last August.

CenterPoint, Minnesota's largest natural gas utility, asked for a rate increase of $54.1 million or 6.4 percent. But in a ruling released Friday, the Minnesota Public Utilities Commission granted an increase of only $27.5 million.

CenterPoint said in a statement that it "just received the final order in our 2015 rate case today and are still reviewing it." Final gas rates are expected to be implemented later this year, the company said, and customers should get a refund due to an interim rate increase levied last fall.

In September, the PUC granted a 5.6 percent interim rate increase — higher than the 3.5 percent increase granted Friday.

CenterPoint last hiked rates in Minnesota in 2014, with the PUC approving a 3.9 percent increase.

CenterPoint, based in Houston, supplies gas to about 840,000 customers in Minnesota; 92 percent of them are residential rate payers. The company serves Minneapolis and parts of central and southern Minnesota. Minnesota is CenterPoint's largest service territory outside of Texas.

CenterPoint said that it primarily needed the new 6.4 percent rate hike to make big capital investments in its pipelines, due to new federal regulations on pipeline safety and integrity. That increase would have added $5.15 per month to the average residential customer's monthly bill.

But the Minnesota Attorney General's Office and the Minnesota Department of Commerce argued before the PUC for a smaller rate increase than CenterPoint had proposed. Both agencies advocate on behalf of rate payers.

"Commerce requested a 45 percent overall reduction from CenterPoint's original proposed rate increase," said Ross Corson, a department spokesman. "In a nutshell, we believed the utility's rate proposal contained unreasonable and excessive expenses, while its revenue forecasts were too low."

The attorney general's office recommended that less of CenterPoint's proposed increase be assigned to residents and smaller businesses, and more to larger businesses.

"CenterPoint originally sought to impose nearly 90 percent of its requested increase on individual residential consumers," Attorney General Lori Swanson said in a news statement. The PUC's ruling cuts the proposed residential increase from $47.5 million to $15.3 million, she said.