ARIZONA – The energy market in the Southwest has hit a turning point, with battery prices falling so low that the technology is now the least expensive way to provide customers electricity, according to officials from Arizona Public Service Co.
To take advantage of the historic shift, the state's biggest electric company will spend hundreds of millions of dollars to add large, building-size batteries to the power grid across Arizona.
APS will use the batteries to soak up surplus energy on the grid early in the day when solar power plants across the region are pumping out more electricity than the homes and businesses require.
The batteries will then discharge that power in the evening, when the sun sets, solar panels power down for the night, and customers turn on their lights and need the energy.
The 850 megawatts of batteries planned by APS will make better use of the solar already on the grid. They will allow for more people to add solar panels to their roofs and utilities to build more solar power plants without creating problems on the grid, officials said.
"850 megawatts shows you how incredibly transformational what we've seen happening on the grid is and how quickly that has been evolving," APS President Jeff Guldner said.