WASHINGTON, Jan 17 (Reuters) - The administration of President Joe Biden has finalized $1.1 billion in credits aimed to help keep open PG&E Corp's Diablo Canyon nuclear power plant in California, the Department of Energy said on Wednesday.

The $6 billion Civil Nuclear Credit Program was funded by the 2021 bipartisan infrastructure law. The Biden administration set up the credit program to help existing nuclear power plants. It believes the plants are essential to help fight climate change and reaching its goal of what it calls 100% clean electricity by 2035.

The first payment of awards, for Diablo Canyon, California's last nuclear plant, is scheduled for 2025. Diablo's two reactors, which the Energy Department said provide 9% of California's power generation, had been slated to shut in 2024 and 2025.

"Preserving the nation’s nuclear fleet is critical not only to reaching America’s clean energy goals, but also to ensuring that homes and businesses across the country have reliable energy," said Maria Robinson, director of the grid deployment office at the Department of Energy.

The U.S. nuclear power industry does not have a permanent place to put toxic, radioactive waste, a problem its critics say should be fixed before extending the life of reactors. Critics also say nuclear is too expensive to make a dent in fighting climate change.

Friends of the Earth, an environmental group, has sued the U.S. Nuclear Regulatory Commission over allowing Diablo Canyon to keep running while they review their operating license renewal.

U.S. nuclear power plants have suffered in recent years on rising safety and material costs and competition with renewable energy and plants that burn plentiful natural gas. More than a dozen U.S. reactors have shut since 2012.

(Reporting by Timothy Gardner; additional reporting by Nichola Groom; Editing by Aurora Ellis)