 Arizona Public Service, the largest utility in the sunny southwestern state, committed itself Wednesday to 100 percent carbon-free power by 2050. The promise includes interim targets of 65 percent clean electricity by 2030, with 45 percent coming from renewables, and removing coal from its portfolio by 2031. With this decision, APS joins a growing list of major electric utilities committing to decarbonize their production. Xcel Energy, which spans eight states in the center of the continent, kicked off the trend in late 2018. It was joined by Duke Energy , New Jersey-based PSEG , DTE Energy and more. The APS commitment is notable in that Arizona has not passed sweeping climate or carbon policy at the state level. Yet clean energy policy has gained traction in other forums, like a recent unsuccessful ballot initiative and in deliberations at the Arizona Corporation Commission, the elected utility regulatory body. Acting now, APS can set the terms of the ongoing debate on how to modernize the states power supply. 