The pause affects billions of dollars and is delaying home repairs, factory construction and other projects, many in states that voted Republican.

Legal experts said the president was testing the boundaries of executive power with aggressive orders designed to stop the country from transitioning to renewable energy.

In a sweeping order, President Trump halted federal approvals for new wind farms, in a move that could affect projects on land and in the ocean.

The president said he’d declare an energy emergency, increase drilling and end support for electric cars. His pivot to oil and gas follows the hottest year in recorded history.

The fire at the Moss Landing plant, which stores electricity for the power grid, was unrelated to wildfires in Los Angeles.

The loan guarantees are one of the final attempts by the outgoing Biden administration to encourage power companies to cut emissions while trying to keep rates down.

Wright, the founder of a fracking firm, testified that he would back all forms of low-carbon energy as well as gas, oil and coal.

With a lucrative tax credit, the Biden administration is hoping to establish a new industry that might help fight climate change.

Some fear Donald Trump could freeze the Energy Department’s loan office, which supports electric vehicles, geothermal, nuclear and other novel technologies.

© Philip Cheung for The New York Times

What the U.N. negotiations, known as COP, can (and can’t) do to combat climate change.

© Rafiq Maqbool/Associated Press

Some fear Donald Trump could freeze the Energy Department’s loan office, which supports electric vehicles, geothermal, nuclear and other novel technologies.

© Philip Cheung for The New York Times