Arizona's Grid Battery Growth Spurt: Will it Last?
Arizona has become a leader in grid battery growth, installing more battery capacity than every state except Texas in the first half of 2026. This trend continues from last year, when Arizona edged out California in both storage and utility-scale solar additions.
Arizona welcomed three new battery projects with 250 megawatts/1 gigawatt-hour of storage each - Beehive, Catclaw, and Pediment - plus several smaller ones. The state also effectively tied Florida for the second most solar installations in the first half of this year and rounded out its portfolio with 300 MW of gas power and 500 MW of wind.
To be clear, Texas and California still have far more solar and storage plugged into their grids. However, Arizona is expanding the map of grid storage dynamism, though some renewable energy advocates worry that a recent turn against clean energy in the state could cause the growth to fizzle out.
Arizona's utilities are served by a handful of vertically integrated monopoly utilities, namely Arizona Public Service (APS), Tucson Electric Power, and the Salt River Project. The state does not have a Texas-style free market for energy or a California-style mandate or policy apparatus. However, Arizona does have ample sunshine and clear, dry weather, making solar the obvious winner for cheapest kilowatt-hour of electricity.
A rapid buildout of solar projects leads to diminishing returns unless you use batteries to store up surplus solar during the sunniest hours of the day. Autumn Johnson, executive director of the Arizona branch of the Solar Energy Industries Association, notes that the wave of storage projects built in recent years is the result of contracts the utilities signed in the heady times of 2018 and 2022.
However, the political landscape in Arizona and nationally has shifted since then, casting a pall over the future of the state's solar and storage buildout. The Trump administration gutted Biden's climate law last year, though it preserved tax credits for batteries specifically. APS abandoned its own climate goals, and the utility regulator is picking performative fights with clean energy instead of pushing the utilities to be more ambitious.
The state legislature this year proposed "a record number of terrible energy bills," Johnson said, including ones to mandate that 85% of electricity capacity come from dispatchable or baseload sources (not intermittent renewables) and to label wind and solar farms a "public nuisance" if they fall within 4 miles of a residential property.
APS, the biggest battery builder in the state, said in a July planning session that it was excluding four-hour duration batteries from modeling for its long-term energy plans, limiting the options to those with six to eight hours of duration. This change could impact the state's ability to keep its top spot in energy storage leadership.
At the very least, construction will continue at a rapid clip through 2026, according to the EIA data, anchored by the nearly finished Maricopa Energy Center, which includes a 550-MW/2.2-GWh-hour battery. Seven battery projects are already under construction for 2027 completion, ranging from 100 MW to 300 MW.
