My "pro" heatpump water post (non AI written)
I feel there's been a flurry of posts against heatpump water heaters (big-gas?) so I wanted to post my own, personal experience.
I understand all situations are different, and so this might not apply to everyone. But I also feel that a lot of the "cons" arguments should specify the same: they don't apply to everyone as well.
We're a family of 3 in San Mateo, replaced gas with heatpump in 2023.
- you need to redo all your electricity
No, there are plenty of 110V heatpump water heaters options. And my own 220V heatpump water heater actually **never** uses the 220V. It seems plenty happy with 110V and uses ~400W of power. Had I known I would not have paid for the 220V / 30A circuit.
- noise
I guess it depends where it's located. Mine's in the garage, and yes it does make some noise, a bit more than a fridge. But only when it's running. I can't hear it from the living room if the garage door is closed. My washing machine and dryer, both in the garage as well, make more noise, that I can actually hear from the living room.
- cost to install
I've seen crazy prices thrown around like 7k *WITHOUT* electric work. Not sure if those models are gold plated or what...
Mine was 5k, and half of that was the electrical upgrade (that I feel I should have gone 110V and could have avoided). The water heater itself was 2k + 500 of install work.
Out of that we got a rebate of ~$3000 from PCE (peninsula clean energy).
- cost to run
For 1000 gallons of hot water. from 55F -> 120F. 1BTU is needed to increase 1 pound of water of 1F. So 1000 gals * 8.34 poud/gal * (120 - 55) = 542100 BTU / (100 000 BTU/therm) = 5.421 therm
for gas: assume gas efficiency is 95%, that's 5.7 therm, at $2.8 / therm that's ~$16
for electricity: 542100 BTU / (3412BTU/kWh) = 158.9 kWh, with UEF 4 that's ~40kWh at $0.45 / kwh that's $18, so 12% more. But with TOU you can go down to ~.35, which would be ~$14, so 14% less. I'm guessing most of those new units have the smarts to set schedule.
I'm sure we can go and pick different numbers here and there, but it's not like electric is twice as expensive.
Anyhow, again, my own positive experience with HPWH