What’s the real carbon savings from a heat pump vs gas furnace?

[ThomasT]

I’m trying to figure out if my family’s plan to install a heat pump this fall is actually a good move for reducing our home’s carbon footprint, or if the manufacturing and grid reliance issues mean our old gas furnace was somehow better in the long run.

[Kenneth_A]

I had a heat pump installed this fall after weeks of back and forth. It cut our winter bill a bit, but we kept the gas furnace as a backup for the coldest nights. The big question for us was the carbon footprint. In our region the grid is getting greener, so the heat pump can lower emissions over time, but if your electricity is mainly from fossil sources now, the advantage is smaller and could flip if the grid changes.

[RyanT]

I tried to do a rough plan around costs. Upfront cost was steep, and the payback depends on how long you stay. We also had to seal gaps and fix ducts; without that, the heat pump works harder. Also the manufacturing footprint exists, but I haven't found a simple answer on how it compares to a gas furnace over 15-20 years.

[NicholasH]

Two weeks ago I ran a little test: no space heaters, let the heat pump run. The house stayed within a degree of target on milder nights, but the outdoor unit hummed and I could hear it during the afternoon when it ran longer. It felt louder than I expected and I kept worrying about reliability in a real cold snap.

[MadisonMS]

Are you sure the real problem is the heating source, or is the bigger issue insulation and drafts? If the house leaks air, you might not save much no matter what you install.