“We are fortunate that Arizona is part of the Western Interconnection,” says Barrios. “In the western grid, if a company requires additional resources, they can turn to one of their neighbors for help.”
North America is comprised of two major and three minor alternating current (AC) power grids or “interconnections.” The Western Interconnection stretches from Western Canada south to Baja California in Mexico, reaching eastward over the Rockies to the Great Plains. The electric utilities in the Western Interconnection are electrically tied together during normal system conditions and operate at a synchronized frequency.
The benefit of this is, for example, when it’s 113 degrees as it was in Tucson this week, it will only be in the mid-70s in Seattle. They may have a surplus of electricity they sell to Arizona if the need presents itself.
“When summer comes along, we have to make additional purchases to satisfy our customers’ energy needs. Given what happened last summer, TEP worked very hard to secure adequate resources,” says Barrios.
Arizona is home to Palo Verde Generating Station, the nation’s largest producer of clean, carbon-free electricity. APS operates the power plant and both APS and SRP have ownership in the plant, which produces enough electricity each year to power 4 million homes and businesses in the Southwest. Other power resources that make up Arizona’s energy mix include hydroelectric, solar, natural gas, wind, coal, and biomass (converting wood products to steam). Despite Arizona’s continued population growth, a new nuclear power plant is not on the horizon.