The Environmental Investigation Agency (EIA), an international NGO based in Washington, D.C., is urging HVAC&R stakeholders in the U.S. to get engaged in the process of setting national standards and codes for expanding the use of hydrocarbons in air-conditioning and heat pumps.
“Meeting our net-zero 2050 targets is going to require basically a transition after 2030 to ultra-low GWP refrigerants,” said Christina Starr, Senior Manager of Climate Campaigns at the EIA. “It is totally possible to enable hydrocarbons across the [AC and heat pump] sector before the end of this decade, but we need the industry experts to get engaged and open up the discussion on this.”
“Meeting our net-zero 2050 targets is going to require basically a transition after 2030 to ultra-low GWP refrigerants.”Christina Starr, EIA
Starr delivered these remarks during her presentation in the Technology Transition Policy Panel session at the ATMOsphere (ATMO) America Summit 2023 on natural refrigerants. The conference took place June 12–13 in Washington, D.C., and was organized by ATMOsphere, publisher of Hydrocarbons21.com.
The UL (Underwriters Laboratories) and American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) are the bodies that initially approve changes in safety standards for appliances and commercial equipment in the U.S., followed by the U.S. Environmental Protection Agency (EPA), and model and local/state authorities.
Starr noted that the UL approved higher charge limits for hydrocarbon-based commercial refrigeration display cases in October 2021 under the UL 60335-2-89 standard Edition 2 and in May the EPA proposed adopting those limits under Significant New Alternatives Policy (SNAP) 26. Moreover, 11 states have adopted updated building codes including UL 2-89 Edition 2 updates for hydrocarbons, and many others reference EPA SNAP approval as triggering an update in their building codes.
The EIA would like to see the UL adopt similar charge updates for air conditioners and heat pumps.
Harmonizing with international standards
In May 2022, the International Electrotechnical Committee (IEC) approved higher charge limits for propane (R290) and other flammable refrigerants in residential air conditioners, heat pumps and dehumidifiers.
The new IEC 60335-2-40 ED7 global standard allows up to 988g (2.2lb) of R290 in a (fixed) split AC unit and 304g (0.7lbs) in a non-fixed unit, while existing regulation in the U.S. only permits 114g (0.3lb) of propane in fixed or non-fixed units (including outdoors), explained Starr.
“We need to look at harmonizing with the IEC standard,” she said. “We have been seeing some great progress lately in this area, especially for refrigeration. Now we need to turn attention to tackling the AC and heat pump sector.”
“We have been seeing some great progress lately in this area, especially for refrigeration. Now we need to turn attention to tackling the AC and heat pump sector.”Christina Starr, EIA
The U.S. market is currently transitioning from R410a, which has a 20-year GWP of 4,715, to R32, with a 20-year GWP of 2,690, and HFO blends. While R32 offers some mitigation potential compared to the baseline scenario, it’s “not getting us where we need to go in terms of our climate goals by mid-century,” noted Starr.
“This is where natural refrigerants, including propane, have a lot of potential,” she added.
Phasing down the use of HFCs is also being driven by the Kigali Amendment and AIM (American Innovation and Manufacturing) Act schedule.
To advance the discussion around hydrocarbon safety standards, Starr called on manufacturers, end users and other industry stakeholders to get involved in the committees overseeing the work, like the UL 2-40 committee and the ASHRAE 15 committee.
“We need to see committees forming to advance this discussion,” she said. “The UL is open for proposals on this.”
Indirect outdoor systems
During her presentation, Starr also noted that ASHRAE is currently discussing the hydrocarbon charge limits of indirect outdoor residential air-conditioning and heat pump systems like monoblocs under its ASHRAE 15 standard. Hydrocarbon monoblocs are increasingly popular in Europe.
If passed, this standard would potentially allow up to 5kg (11lb) of R290 in an outdoor unit. It is expected for public review shortly, she added.
“We need to look at other applications that are not covered here, such as window units, portable units, split units, rooftop units etc.” she said. “We need to think about the design of this equipment and how we can safely design this equipment using these very energy-efficient, low-GWP hydrocarbons.”