The Senate’s draft energy bill (S2829) covers a lot of ground. It reinvents the siting of energy facilities, supports expansion of vehicle charging stations, and makes important changes that may help gas companies shift towards providing networked geothermal heat.
The bill makes little change to our current MassSave programs for home insulation and heat pump installation. I agree with the implicit conclusion that our MassSave programs are moving roughly in the right direction for now.
There is one statutory change proposed relative to heat pumps that is critical to adopt in the current calendar year. It is necessary to preserve availability of heat pumps in Massachusetts. We need to conform with evolving federal laws governing heat pump refrigerants. Section 41 of the bill adds a new section to the building inspection chapter of the General Laws (Chapter 143):
Section 101. Notwithstanding any provision of the state building code, specialized code or any other general or special law or municipal ordinance to the contrary, refrigerants identified as an alternative for use pursuant to, and in accordance with, 42 U.S.C. 7671k shall be acceptable for use in the commonwealth.
Here is the background: Refrigerants are the working fluids that heat pumps compress and circulate to transfer heat. Every heat pump contains several pounds of refrigerant which flow back and forth between the indoor and outdoor components. The current generation of heat pumps use a refrigerant known as R-410A which is a mix of two chemicals — R-32 and R-125. Both appear to be non-toxic for household occupants, even if they leak. R-32 is a good refrigerant — i.e., its physical properties make it suitable for use in heat pumps — but it is flammable. R-125 is a so-so refrigerant, but a good flame retardant and it is added to make the mixture non-flammable.
Unfortunately, R-125 is a potent greenhouse gas — over 2000 times more potent than carbon dioxide. So, pursuant to international treaty obligations the EPA is implementing rules to phase it out. Heat pumps containing R-125 may not be imported into or manufactured in the United States after January 1, 2025 and may not be sold after January 1, 2026. The ready alternatives to R-410A are refrigerants which are mildly flammable, notably pure R-32. Current Massachusetts building code language authorizes the use only of refrigerants that are both non-toxic and non-flammable. The building code update cycle will not lead to a timely revision, so the language above is necessary to allow use of R-32 and other mildly flammable refrigerants that have been deemed safe alternatives under the federal law that governs transition away from chemicals that are ozone depleting and/or have high global warming potential.
Eventually, our building code will catch up with the evolution of the heat pump industry. In the interim, we will, in effect, be relying on federal policy and industry standards to assure the safe use of mildly flammable refrigerants. At a later date, this section may become unnecessary.
Additional background appears in the following posts on my site:
I agree with your vote
Thanks very much for this update/summary/explanation. It’s a confusing arena and hard to keep current with all that is happening at the state and federal level.
When might the heat pump industry catch up with the building code? I assume there is a reason for the non-flammable requirement in the building code?
It’s about the building code catching up with the industry and federal regulations — we have to move to slightly flammable refrigerants, and the building code needs to define how we can do that safely.
It appears to be a battle of climate safety laws v/s fire safety laws. So if you already have a heat-pump installed, hope it doesn’t leak and needs to be recharged ever again. If not, reserve for replacement of your heating system again, choosing not to heat your house or taking your fossil fueled heater out of mothballs. This is going to be an interesting battle. I will be a spectator at this game on the sidelines. The laws of thermodynamics are always win.