In one of the biggest victories for U.S. climate action in a decade, Congress has moved to phase out a class of potent planet-warming chemicals and provide billions of dollars for renewable energy and efforts to suck carbon from the atmosphere as part of the $900 billion coronavirus relief package.

The legislation, which Congress approved moments before midnight Monday, wraps together several bills with bipartisan backing and support from an unusual coalition of environmentalists and industry groups.

It will cut the use of hydrofluorocarbons (HFCs), chemicals used in air conditioners and refrigerators that are hundreds of times worse for the climate than carbon dioxide. It authorizes a sweeping set of new renewable energy measures, including tax credit extensions and new research and development programs for solar, wind and energy storage; funding for energy efficiency projects; upgrades to the electric grid and a new commitment to research on removing carbon from the atmosphere. And it reauthorizes an Environmental Protection Agency program to curb emissions from diesel engines.

The legislation also includes key language on the “sense of Congress” that the Energy Department must prioritize funding for research to power the United States with 100 percent “clean, renewable, or zero-emission energy sources” — a rare declaration that the nation should be striving toward net-zero carbon emissions.

“This is perhaps the most significant climate legislation Congress has ever passed,” said Grant Carlisle, a senior policy adviser at the Natural Resources Defense Council.

The HFC measure, which empowers the EPA to cut the production and use of HFCs by 85 percent over the next 15 years, is expected to save as much as half a degree Celsius of warming by the end of the century. Scientists say the world needs to constrain the increase in the average global temperature to less than 2 degrees Celsius compared with preindustrial times to avoid catastrophic, irreversible damage to the planet. Some places around the globe are already experiencing an average temperature rise beyond that threshold.

Advocates say the $35 billion of new funding for renewable technology and energy efficiency in the legislation will also help reduce pollution that is driving global warming and provide a much-needed boost to federal energy programs that haven’t been updated since 2007.

After passing a record $3 trillion in economic relief this spring, Congress went months without a new aid package even as the coronavirus pandemic worsened. (The Washington Post)

“It doesn’t have regulations or mandates in it,” Sasha Mackler, director of the energy project at the Bipartisan Policy Center, said of the energy package. “But from the bottom up it’s advancing the technology that’s needed. … This is definitely a bill that creates the enabling conditions for decarbonization.”

Support among lawmakers for the package suggests that tax incentives and research funding may be a rare area of common ground between two parties that have been divided on climate change.

Despite President Trump’s numerous efforts to roll back climate regulations, leading Republicans backed the package, which has been a top priority for Sen. Lisa Murkowski (R-Alaska) for years. Senators John Barrasso (R-Wyo.) and John Neely Kennedy (R-La.) helped craft the bipartisan agreement to scale down polluting refrigerants.

“These measures will protect our air while keeping costs down for the American people,” Barrasso, chair of the Senate Environment and Public Works Committee, said in a statement Monday.

Sen. Thomas R. Carper (D-Del.), an ally of President-elect Joe Biden and co-sponsor of the HFC provision, called it “a watershed moment” that bodes well for lawmakers interested in working with the incoming administration on climate change.

“The debate on whether climate change is real is over. It is real. It’s not getting better,” Carper said in a recent interview. “Our Republican colleagues, they get it, for the most part.”

The agreement comes on the heels of a major United Nations climate report, which found that nations’ current plans to reduce greenhouse gasses are just one-fifth of what’s needed to avoid catastrophic warming.

If leaders invest heavily in green infrastructure and renewable energy as part of coronavirus stimulus spending, the world could trim as much as 25 percent from its expected 2030 emissions, the U.N. report said.

Democrats and environmental groups say the legislation is not quite the sweeping “green stimulus” that’s needed. Though it meets Biden’s call to extend tax incentives for solar and wind generation and provide more money for clean energy research, it falls short of his requests for aggressive subsidies for electric vehicles and new requirements that utilities eliminate their contributions to global warming by 2035.

It also excludes a provision from earlier versions of the bill that would have set voluntary standards for energy efficiency in buildings — something that could significantly curb emissions from cities.

“Let’s be clear: Are these provisions enough to meet the demands of the science? No,” said Senate Minority Leader Charles E. Schumer (D-N.Y). “But are they a significant step in the right direction? Yes.”

The HFC rule lays the groundwork for the United States to sign onto the Kigali Amendment, an international agreement in which more than 100 nations committed to replacing the chemicals with refrigerants that have a smaller climate impact. Signed in the final days of the Obama administration, the treaty was never submitted by Trump for ratification by the Senate. By voting to curb the climate pollutant now, Congress has eased the path for approval once Biden takes office.

Included in the energy package are roughly $4 billion for solar, wind, hydropower and geothermal research and development; $1.7 billion to help low-income families install renewable energy sources in their homes; $2.6 billion for the Energy Department’s sustainable transportation program; and $500 million for research on reducing industrial emissions.

It also authorizes $2.9 billion for the Advanced Research Projects Agency-Energy, a program that funds high-risk, high-reward research and that Trump has sought to eliminate multiple times.

The increased funding is expected to make emerging clean-energy technology cheaper and more widespread. This is especially significant for ideas that have proved effective but are struggling to make the jump to commercial viability.

“This is an opportunity to not only make significant advances in climate action and reducing HFCs, but to help maintain leadership of U.S. technology and our competitiveness in that global market,” said Marty Durbin, an energy lobbyist at the U.S. Chamber of Commerce, the largest corporate lobbying group in Washington.

In a boon for renewable energy companies, Congress extended tax credits for wind and solar and introduced a new credit for offshore wind projects, which Heather Zichal, chief executive of the American Clean Power Association, called “America’s largest untapped clean energy source.” One Department of Energy analysis suggested that developing just 4 percent of the total U.S. offshore wind capacity could power some 25 million homes and reduce the nation’s greenhouse gas emissions by almost 2 percent.

But many green groups were critical of provisions dedicating more than $6 billion to efforts to remove carbon from the air and store it, as well as funding for enhanced oil recovery projects, which reuse carbon dioxide to flush residual oil from existing wells.

“It just perpetuates the fossil fuel system,” said Jean Su, an attorney and director of the energy justice program at the Center for Biological Diversity. “If you pass something like this, you’re not doing the best we can do in terms of transforming our energy system.”

Others see carbon capture as a necessary tool for mitigating emissions from sources that aren’t easily decarbonized, such as air travel. The bill directs the energy secretary to estimate “the magnitude of excess carbon dioxide” that needs to be removed from the air to stabilize the climate.

The legislation includes more than $11 billion for nuclear energy — a zero-emission energy source that nonetheless poses other environmental risks.

“It’s not something necessarily we would have written,” said Toby Short, vice president of federal affairs for the Environmental Defense Fund. But he thinks the investments in renewables outweigh the negatives. “You can’t let the perfect be the enemy of the good,” he added.