Is my heat pump really reducing overall energy use or just shifting it?

[Scott_H]

I’m trying to figure out if my family’s new heat pump is actually reducing our overall energy use, or if we’re just shifting the source. Our electricity bill has gone down, but I’m unsure how to account for the grid’s generation mix.

[AmeliaYJ]

Got a heat pump last year. Our bill dropped, but I started keeping a simple log of kWh by month. Some months show a real drop, others not so much. The grid around here shifted toward more renewables at certain times, so it’s tough to separate the heat pump’s effect from changes in generation mix. I’m not confident I’m reading it right.

[JustinM]

I tried putting a cheap meter on the heat pump circuit and comparing to the rest of the house. The heat pump itself pulled less energy overall, but there were times when the backup heat kicked in and bumped the usage up briefly. Hard to tell if that’s normal or a sign something’s off.

[TylerR]

I wonder if we’re just getting cheaper power during the same hours we’re using the heat pump. The weather was milder this year too, so maybe we would have used less anyway. I haven’t calculated emissions or a full baseline, just eyeballed the bill.

[Mia32]

One question for the group: could the real issue be thermostat behavior rather than the grid mix, like setpoints and occupancy patterns driving the load?