Congress has passed a $900 billion pandemic relief and stimulus package. The bill, coming after months of negotiations between Democratic and Republican leaders and Trump administration officials, offers a $600 payments to Americans earning below $75,000 as well as support for small and large businesses. The personal payments going straight to families are half the amount provided last spring.

But the bill also contains a surprise bonus for climate change activists: a bipartisan measure to enact new limits on hydrofluorocarbons (HFCs), a gas used in millions of pieces of equipment owned by Americans—most home and automotive air conditioners as well as refrigerators in air conditioning and refrigeration. Recharging any of these systems after a leak would become more expensive once HFC supplies dwindle and prices rise.

The stimulus bill would force the US into compliance with the Montreal Protocol’s Kigali amendment. Supporters of the regulations believe the agreement alone, with US participation, could shave half a degree Celsius off global temperatures by 2100, according to the World Resources Institute—one-third of the Paris agreement’s goal of 1.5°C. However, they admit that HFC’s are but a very small percentage of overall greenhouse gas emissions.

Critics of the regulation remind us that replacement equipment would have to be manufactured and the systems will get costlier as they will have to be redesigned to use one of the environmentally acceptable HFC substitutes. Many of these eco-friendlier alternatives already carry a hefty price premium, and that’s before they get the playing field tilted in their direction by Congress. In addition, some of the new refrigerants are classified as flammable.

Businesses of all sizes rely on HFCs, from restaurants that use them in refrigerators and freezers to pharmaceutical makers that need to create cold conditions in the manufacturing process. For the latter, scarce HFCs could confer an advantage on industrial competitors in China that don’t face the same constraints.

If passed, the provisions in the bill become the most significant expansion of US climate law since 2007, when the Supreme Court ruled that the Environmental Protection Agency can regulate greenhouse gases under the Clean Air Act. Efforts by a Biden presidency to curb CO2 and methane produced by the energy industry would likely rely on that authority, not new laws that would have to pass congress.

Other climate action included in the bill are $35.2 billion for research on carbon removal, renewables, energy storage, and other low-carbon technologies, as well as extending key tax clean energy tax credits.

The bill starts the dismantling of President Trump’s job friendly de-regulation that gave American manufacturing a more level playing field with China.

The flip side to the costs imposed on HFC users is the potential windfall to the companies that make the substitutes. They are led by Honeywell and Chemours, both of which have patented HFO-1234yf and other pricey alternatives, from which they are predicting billions of dollars in additional revenues. Coincidence or not, the bipartisan Senate dream team who spearheaded these measures is comprised of Republican John Kennedy of Louisiana, where Honeywell makes refrigerants, and Democrat Tom Carper of Delaware, where Chemours is headquartered.