Ahead of California’s inaugural Global Climate Action Summit, Gov. Jerry Brown announced that the state will supply 100% of its energy from sources that don’t emit greenhouse gas emissions through Senate Bill 100.

Brown also signed an executive order requiring the state to become carbon-neutral by 2045, which calls for offsetting the 16% of state emissions that come from sectors other than electricity production, like transportation.

There’s no wiggle room in these proposals, either — Brown signed both pursuits into binding law.

“This bill and the executive order put California on a path to meet the goals of Paris and beyond. It will not be easy,” Brown said in a press release. “It will not be immediate. But it must be done.”

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The new measures accelerate previous climate commitments that the state has made in recent years and signals its ambition to help ensure that the US maintains its commitments made under the Paris climate agreement, even as the federal government undermines national environmental regulations.

In numerous ways, California has emerged as a primary adversary of the Trump administration’s environmental agenda.

After President Trump withdrew from the Paris climate agreement, California joined other states and cities to announce its independent commitment to the global pact. When the Trump administration rolled back car emissions standards, California announced it would be maintaining those standards, essentially forcing the US car market to split in half because vehicle manufacturers would have to accommodate both sets of standards.

And when the Environmental Protection Agency dismantled the Clean Power Plan, a regulation intended to curb power plant emissions, California joined a lawsuit to overturn the updated rule.

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This activist role is significant because the state is the fifth largest economy in the world, allowing it to shape larger national trends, according to NPR.

“In California, Democrats and Republicans know climate change is real, it’s affecting our lives right now, and unless we take action immediately — it may become irreversible,” Senator Kevin de León, the author of SB 100, said in a press release. “Today, with Governor Brown’s support, California sent a message to the rest of the world that we are taking the future into our own hands; refusing to be the victims of its uncertainty.”

“Transitioning to an entirely carbon-free energy grid will create good-paying jobs, ensure our children breathe cleaner air, and mitigate the devastating impacts of climate change on our communities and economy,” he added.

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California already gets around 32% of its energy from renewable sources, but the unreliability of solar and wind power causes energy production to fluctuate greatly depending on day-to-day weather forecasts.

Going forward, the state will have to invest in better energy storage systems and improve the strength of the energy grid so that electricity can be better moved throughout the state, according to NPR.

California is also going to invest in nuclear energy, which isn’t renewable but is permissible because it doesn’t emit greenhouse gases. Nuclear energy is controversial for the huge amounts of water it demands and its potential for environmental pollution.

Other states throughout the US, including Hawaii, have created plans to reach 100% renewable energy and cities throughout the country are already well on their way to this goal.

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Bringing a state as a massive as California to fully renewable status will be challenging, but the accelerating nature of climate change demands nothing less than bold plans.

“California is committed to doing whatever is necessary to meet the existential threat of climate change,” Gov. Brown said in his SB 100 signing message. “This bill, and others I will sign this week, help us go in that direction. But have no illusions, California and the rest of the world have miles to go before we achieve zero-carbon emissions.”