California embarked on a new phase of climate leadership Friday, as Gov. Gavin Newsom signed a package of bills aimed at charting the state’s course through a perilous energy transition.

The legislation includes an extension of California’s marquee program to reduce pollution from refineries and power plants, reaffirming the state’s commitment to limit planet-warming emissions.

But changes to that cap-and-trade program — and accompanying bills on electricity and fuel supply — reflect a struggle by lawmakers to manage both the impacts of climate change and the move away from fossil fuels, which each threaten to drive up energy costs for residents.

“We have to effectively transition,” Newsom said before signing the bills at the Academy of Sciences in San Francisco. “This is not an i

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