CenterPoint Energy said Monday it will seek another rate hike for its 823,000 natural gas customers in Minnesota.

The Houston-based company said in a statement and in filings with the Minnesota Public Utilities Commission that it seeks a $54 million annual increase, or 6 percent, in revenue. If approved, the new rates would increase the average residential customer's bill by about $5 per month, the company said.

The company requested a 5.6 ­percent interim rate to take effect in October while the request is considered by regulators. The company won a $33 million, or 3.9 percent, rate increase in 2014.

Joe Vortherms, division vice president of CenterPoint Energy's regional gas operations, said in a statement that the increase is for investments such as ongoing pipeline replacement programs for safety and ­reliability.

"These capital investments, which are the primary reasons for this proposed increase, help ensure that we have a modernized, technologically advanced natural gas system that will continue to meet the needs of customers now and in the future," he said.

The increase would apply to the distribution charge on bills, which is 40 percent to 50 percent of the total. The price of gas changes monthly, and the utility passes on those changes each month with no markup.

Under the proposal, the basic charge for residential customers would rise from $9.50 to $11.50 a month. In its last rate hike, the basic charge went from $8 to $9.50. The delivery charge, based on the amount used, also would go up if the rate hike is approved.