The two major electric utilities serving the Valley said Wednesday they have plenty of reserves available to keep customers' air conditioners humming during the summer heat this year.
Arizona Public Service representatives told the Arizona Corporation Commission they have an 18 percent reserve over the anticipated peak use this summer, while Salt River Project representatives said they have a 13 percent reserve.
The last major summer electricity crisis came in 2004, when a transformer fire at the Westwing substation in the northwest Valley prompted APS to appeal to its customers to voluntarily conserve power.
Daniel Froetscher, general manager of energy delivery for APS, said all needed repairs have been completed at Westwing, and improvements have been made at other substations, too.
"We believe we have contingency planning in place to deal with any unexpected issues," he said.
Although growth has slowed in both utilities' service territories, it hasn't disappeared entirely, and both companies are forecasting increases in their peak load this summer. However, demand for energy is not expected to be a record.
The record peak was in 2006 during an unusually hot and humid 118-degree day.
Peak load is the amount of electricity that customers use during the hottest hour of the hottest day of the year, and that is the capacity that utilities have to prepare for.
APS is expecting a peak load of 7,202 megawatts on its system this summer, and the utility has 8,485 megawatts available. SRP is forecasting a peak load of 6,896 megawatts and has 7,794 megawatts available.
About 2 percent of APS' power this year will come from renewable sources such as solar and wind, said Tom Carlson, APS fuels director. About 5 percent of SRP's power will come from renewables, a greater figure because the project has access to hydropower.
APS is under a mandate from the commission to obtain 15 percent of its energy from renewables by 2025.
The subject of renewable energy led to a spirited discussion among commissioners Wednesday. Commissioner Kris Mayes expressed dismay that most of the renewable energy used in Arizona is coming from out of state - for example, wind power from New Mexico and geothermal from Utah. She said wind potential in northern Arizona is not being tapped.
But Commissioner Jeff Hatch-Miller said utilities should obtain renewable power from the most economical sources regardless of location.