(KTEN) — The Oklahoma Corporation Commission has voted to make Oklahoma Gas & Electric's interim rate increase permanent.

The interim rate, which OG&E implemented in July, resulted in a 1.9 percent monthly increase — a little more than $2 for the average residential power customer.

AARP Oklahoma raised questions about the utility's original proposed rate hike of around $163 million, even though OG&E estimated that its profit this year would be as much as $390 million.

"We want the lights to come on when you flip the switch, but we also know it needs to be affordable," said Chad Mullen, advocacy director for AARP Oklahoma. "We were able to intervene — unlike Texas and other places that aren't regulated — and so there were some concessions. The rate increase was cut down to just $30 million, there was an additional $3 discount for low-income individuals."

In a statement, OG&E said the rate adjustment is a part of the company's efforts to harden, secure, and modernize the electric grid:

"Ensuring a reliable electric grid to serve the growing needs of OG&E's customers requires ongoing infrastructure investments like upgrading and installing new equipment on overhead and underground power lines."

Ardmore property manager Kori Thompson has already seen the impact of the interim rate hike on her tenants.

"They've texted us asking, is there something wrong with their house? Is it the windows or needing updates? It's all across the board, electric bills have went up," she said. "We've been having more people late on rent because they are having to pay higher utility bills."

The OCC's ruling last week also includes a monthly increase to the low-income assistance program credit and a refund to customers related to a reduction in the state's corporate income tax rate.