If you’ve been keeping an eye on HVAC trends, you’ve probably heard a lot about GWP — Global Warming Potential. It’s the number that supposedly tells us how much a refrigerant contributes to global warming compared to carbon dioxide. Seems simple enough. But like a lot of things in this industry, the deeper you dig, the more complicated it gets.
The truth is, GWP isn’t carved in stone. It’s a theoretical model based on lab measurements, assumptions, and projections — not something anyone’s measuring directly in the real world. In fact, different organizations report different GWPs for the same refrigerants. One agency might say R-410A has a GWP of 2,088, while another rounds it up to 2,100 or down to 1,900. These aren’t just rounding errors — they reflect uncertainty in the science.
And here’s another wrinkle: GWP is usually measured over a 100-year timeframe. Why 100 years? Why not 20, or 500? The answer is, that’s just the convention someone picked. But it matters — some refrigerants look much worse (or better) depending on the time horizon you use. Short-lived chemicals might have sky-high 20-year GWPs, but almost no impact at 100 years. Others are the reverse.
Bottom line? The GWP number is more of a ballpark estimate than a hard fact. And yet policies, bans, and product rollouts are being built around it — as if it’s gospel.
This doesn’t mean we throw caution to the wind or ignore environmental concerns. But it does mean we should be honest about what GWP is: a work in progress. If you’re a homeowner trying to make a smart, future-proof choice, just know that the numbers driving the latest refrigerant shifts aren’t as locked-down as they may seem.
As always, my advice is simple — look past the hype. Focus on what works, what lasts, and what makes sense for your home. The science may change. Solid equipment and honest advice never go out of style.