Two American Electric Power subsidiaries are asking state regulators to approve a rate increase worth 100 million dollars a year.

If the Public Service Commission approves the 12 percent rate hike, residential customers of Appalachian Power and Wheeling Power who use one-thousand kilowatt-hours a month would see their monthly bills increase by nearly $6.50 a month.

The increase would go in effect on July 1.

The PSC approved a settlement agreement with the utilities in July 2006 that allows for periodic adjustment of rates to pay for environmental construction projects, fuel and purchased power.

Appalachian Power serves customers in West Virginia. Wheeling Power's customers are primarily in Marshall and Ohio counties.