Harnessing America's heat pump moment

Keeping my family warm was a real struggle that week. The next spring, I went to Costco and bought a big tri-power generator and wired up a generator interlock on the electric panel. Now if we lose power, we can run the natural gas furnace & blower with no problems. I can also power the generator from my home's natural gas supply instead of making frequent trips for gasoline.

So I'd say heck no to swapping the natural gas furnace for a heat pump. I'd much rather use natural gas to power both the generator and the furnace/blower than risk needing more electricity to keep my family warm than my setup can handle.

The math actually works out in many places unless you have cheap gas and expensive electricity. Its also better then to burn the gas at a power plant at 60% efficiency then 300-400% efficiency at the heat pump than pipe and burn the NG at 80% efficiency in your furnace.

All this to say: if your pump can't handle +5°c, I wonder if you got scammed or if there are other factors at play? Is your house insulated at all? Do you keep your windows open throughout winter? Your experience is so different from mine it's hard to believe we're even talking about the same technology!

I'm doubly suspicious of areas that combine mass-electrification with reducing availability of the most reliable alternate source of electricity (i.e. generators). California in particular is pushing to make generators increasingly hard to obtain.

Mitsubishi sells heat pumps that produce 14kw of heat output all the way down to 5f at a COP of 2.3.

Resistive heat has a COP of 1, by definition.

Do you know the size of your oil burner? It's likely over 20kw output.

It's not that pumping heat cannot work sufficiently at cold temperatures, it's that you are expecting the electric car rated 100 horsepower to go as fast as the gas car rated at 300 horsepower.

An oil burner sized to the same output as the heat pump also would not keep up.

If you installed two of those Mitsubishi heat pumps (which would require two independent 240v circuits), you would be at 28kw output and would not need resistive heat strips. These units also claim 75% rated capacity at -13f so that would be about 21kw of heat output even when very very cold.

If your resistive heat strips activate at any point other than extreme weather events or emergencies, your "system" is not sized properly. They are a massive waste of power and money.

A big part of the problem is that the contractors who are essentially the point of sale for these systems are just obscenely dumb about them. They will sell you utterly undersized units or sell units that aren't rated for cold, as well as just install things so poorly that they drain condensate into your walls and cause mold issues. They had similar problems with Oil burners, but at least those they tended to upsell bigger systems so their ignorance didn't matter. They seem very bad at doing the planning or design required to actually spec out a system, so you have to be your own engineer.

>and that is what the industry needs to work on.

I don't know how the industry is supposed to force contractors to read their very very clear documentation, or follow the very clear instructions (of boiler manufacturers no less) of "You must measure heat load to accurately size a heat appliance".