By Alex Hillbrand, Natural Resources Defense Council
Good news came out of EPA last week in the effort to replace climate-polluting hydrofluorocarbons (HFCs) with safer alternatives.
In the refrigerant business, there’s life before and after “SNAP approval,” when EPA deems better replacement chemicals safe and ready to sell. EPA proposed a handful of them last week, including for six HFC alternatives in air conditioners (ACs) and heat pumps for use in homes and light commercial buildings. EPA also proposed a few separate approvals that raise potential concerns.
EPA’s “Significant New Alternatives Policy” Program office, or SNAP for short, approves and prohibits chemicals used in a variety of consumer and industrial applications. It’s a reliable “safety check” on new substances for potential impacts on the atmosphere, direct exposure and toxicity impacts on users and workers, flammability, and other environmental impacts such as ecotoxicity and air quality. Governments around the world look for the SNAP seal of approval before allowing new chemicals onto the market.
When EPA finalizes this rule, consumers shopping for a new AC or heat pump will be able to ask their local suppliers for a next-generation model that doesn’t contain “R-410A,” the gas used for the last 15-20 years. The rub: local building codes might not yet allow the alternatives, so a permit for installation may require specific approval from a local code official. More on that, and what to do about it, later.
R-410A is an HFC and a big threat to our climate—it has a global warming potential of about 2,000. Each pound that leaks is equivalent to one ton of carbon dioxide emissions, or what comes from burning 100 gallons of gasoline. And that’s roughly the quantity that leaks from every central AC in the U.S. annually (or every two years, if we’re lucky).
Those emissions add up. In 2018, U.S. HFC emissions from ACs and heat pumps equaled the carbon pollution from 8-10 coal-fired powerplants.
ACs and heat pumps using the new refrigerants will see the climate impact of those emissions fall by 75% or more. The six gases slated for approval—including R-32 and five other refrigerant blends that aren’t exactly household names—have global warming potentials between 140 and 700. Although these numbers aren’t 0, and so there’s more work to be done, the new alternatives present a market-ready way to dramatically cut back these products’ emissions.
Today’s proposed approvals should add momentum to this year’s effort in Congress to enact legislation, The AIM Act, to phase down HFCs in the U.S. With the approval of new alternatives, next-gen ACs and heat pumps will enter the market perhaps as early as next year, underscoring that industry is well-equipped to meet the 15-year HFC reduction schedule called for in the bill.
The California Air Resources Board also has a proposal to limit the potency of refrigerants sold in ACs and heat pumps starting in 2023, and today’s proposed alternatives would fulfill those requirements. The EPA action puts a tailwind behind California’s rulemaking, which is to be completed later this year.
The new alternatives will also boost the movement to “decarbonize” buildings by using heat pumps in place of gas furnaces and water heaters. Because they use electricity instead of burning fossil fuels, heat pumps are an important way to reduce home and building carbon emissions, when combined with decarbonizing electricity generation at the same time. Lower-GWP refrigerants like these will help maximize the climate benefit of deploying a growing number of heat pumps.
Safety Standards & Building Codes
For an AC or heat pump to be installed without special approval, local building codes must allow for use of the refrigerant it contains. And, as of today, most building codes have not been updated to allow the refrigerants in EPA’s proposal. Building codes are updated gradually, usually at three-year intervals, and most have not yet considered adding these new refrigerants.
For a time, there was reason to wait. All six refrigerants are considered “mildly flammable” and bear an “A2L” rating from the American Society of Heating, Refrigerating, and Air-conditioning Engineers (ASHRAE). For SNAP or a building code to grant approval, those refrigerants needed to be shown safe.
ASHRAE and Underwriters Laboratories, LLC. (UL) worked for more than a decade to develop appropriate safeguards for ACs and heat pumps using A2L refrigerants, culminating in the recent publications of two standards, ASHRAE 15 2019 and UL 60335-2-40 3rd Ed. These standards ensure that the risk of using an A2L refrigerant is not significantly greater than using today’s choice, R-410A. The standards do so by placing additional requirements on products containing A2Ls, including warning markings, limits on refrigerant quantity, greater ventilation requirements, refrigerant leak sensors, alarms, self-shutoff valves, and more.
EPA’s proposed approvals precisely mirror the substantive ASHRAE and UL requirements, and so serve to endorse the safety of the standards set forth by ASHRAE and UL. Safety is an issue of paramount importance to the SNAP office: under Title VI of the Clean Air Act, EPA is to approve and prohibit substances in order to “reduce the overall risk to human health and the environment.” In this proposal, EPA deems these alternatives to meet those criteria and, with respect to their flammability, that the ASHRAE and UL standards do the job.
This type of safety certification process has been successful in many other cases. Automobile air conditioners in the U.S., for example, have almost completely switched to a different A2L refrigerant, R-1234yf, based on a similar consensus standard written by the Society of Automotive Engineers. About 100 million air conditioners and heat pumps using R-32, one of the gases on the list of six, have sold worldwide under comparable standards by the International Electrotechnical Commission and others. There have been no noteworthy safety implications of either transition.
The State of Washington recently updated its building codes to accommodate A2Ls. Other states have the guidance they need to follow suit now that EPA has proposed approval. But there may still be headwinds; some companies have sought to fan the flames of fear regarding A2L refrigerants to gain competitive advantage or delay markets opening to next-generation products.
With EPA’s weight behind the rigor of the ASHRAE and UL standards, the time has come. State and local building code commissions should begin updating their building codes to accommodate A2Ls at the earliest opportune time. They may precisely follow the requirements put forth by EPA, ASHRAE, and UL. They may also choose to amend them to address additional, perhaps local, concerns, as California officials are considering. But there’s no reason left for inaction altogether.
Refrigeration & Foams
This week’s proposed rule also includes SNAP approvals for several refrigerants in stand-alone commercial refrigerating appliances—basically fridge-temperature coolers at the supermarket—and extruded polystyrene foams. Here we have some concerns. In both cases, EPA proposes to approve HFCs that have higher GWPs than other approved alternatives—in at least one case even higher than substances that were prohibited from these products in prior SNAP rules issued in 2015 and 2016. While these product classes are far smaller emitters than home ACs and heat pumps, these approvals still call for scrutiny.
According to its proposal, EPA has been approached by several companies unable make compliant products under today’s regulations. The companies have asked for these new substances to be approved and provided some documentation of their efforts to make do without them.
EPA reports in the proposed rule that using currently-approved refrigerants in stand-alone coolers would make them too big. There is a safety limit on the quantity of hydrocarbon refrigerant that can be used per compressor in these products, so two separate compressors would be needed. The extra hardware, the industry petitioners contend, would result in units so large they would violate the Americans with Disabilities Act.
For extruded polystyrene foams, EPA reports that manufacturers are unable to create insulation that meets building-code-stipulated performance requirements with the alternatives already approved. The manufacturers report success with the substances being put forth today for approval, which are HFCs blended with hydrofluoroolefins (HFOs) and have about half the global warming potential of their predecessor, HFC-134a.
We’ll be looking into these claims to see if they hold water.