The California Assembly on Tuesday passed SB 100, which would mandate that 100 percent of retail electric sales come from renewable sources by 2045.

The bill, “California Renewables Portfolio Standard Program: Emissions of Greenhouse Gases (SB-100),” directs the Public Utilities Commission to accelerate its mandate that retail electricity sellers produce or procure a continuously rising percentage of energy supplies from zero-carbon sources.

The new schedule requires the current 25 percent standard to rise to 33 percent by the end of 2020; 44 percent by the end of 2024; 52 percent by the end of 2027; 60 percent by the end of 2030; and 100 percent by the end of 2045.

The controversial legislation took two years to move through the state legislature. Although the Democrat leadership aggressively backed the final bill and the Republican leadership fought just as hard against it, the final 44-to-33 vote margin saw some Assembly members on both sides cross party lines.

What appears to have tipped the scales in favor of passage was the release of a state report warning that climate change will cause California to suffer higher temperatures that will increase annual wildfires by 77 percent and cause the seas to rise dramatically, according to the San Francisco Chronicle.

The Los Angeles Times summarized the report as warning: “Heat waves will grow more severe and persistent, shortening the lives of thousands of Californians. Wildfires will burn more of the state’s forests. The ocean will rise higher and faster, exposing California to billions in damage along the coast.”

SB 100 will need a concurrence vote to approve the Assembly amendments. But with former Senate President pro Tem Kevin de León (D-Los Angeles) as its author, the Senate vote is expected to be perfunctory.

Sen. de León, who is running for U.S. Senate against incumbent Sen. Dianne Feinstein (D-CA), hailed the Assembly vote: “This is a huge victory for the state of California.” He added: “It’s a victory for clean air. It’s a victory to tackle climate change and the devastation that it’s leaving in its wake,” according to the Times.

Severin Borenstein, director of the Energy Institute at UC Berkeley, told the San Luis Obispo Tribune that 100 percent renewable energy is feasible. But he added: “The question is, how expensive is it going to be.”

California residential customers use about half as much electricity per capita as the average American. But those retail customers pay about a 50 percent premium for electricity at about 15.2 cents per kilowatt hour, according to the U.S. Department of Energy.

Borenstein commented that the current 25 percent requirement for renewable energy works in California, because a third of state’s electric generation comes from natural gas-fired plants that can quickly be ramped up or ramped down. He warns that with solar power only working when it is sunny, and wind power only working when it is windy, the state will have to invest in massive amount of expensive battery storage.