Southern Arizona heat drives up power grid demand

Extreme heat warnings are scheduled to begin Thursday across Southern Arizona, with temperatures expected to reach 110 degrees by the weekend. The heat has prompted First Alert Weather Days through Sunday.

The U.S. Department of Energy issued an emergency order covering 17 states, including Arizona, directing backup generators to be available in areas at risk. Tucson Electric Power said it is not covered by the order and has been able to manage demand during previous heat waves.

TEP reported a peak demand of 2,500 megawatts on Aug. 6 last year, when temperatures reached 111 degrees. Usage this year has climbed to 2,400 megawatts. The utility said it now has 10 times more battery storage than it had last summer, along with generators that can start within seconds during demand spikes.

TEP said customers should not be worried about losing air conditioning, but encouraged them to limit electricity use when possible. Higher demand can raise energy prices, and the utility offers tips for reducing consumption and bills.