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Comment by nightski | Hacker News Reader

The thing is (especially where I live) I'd still need a gas furnace. We regularly see -20F to -40F in the winter. While the 95% scenario sounds great, in practice still needing gas means we still need all the gas infrastructure. From my understanding natural gas burns pretty clean. The problem is leaks in infrastructure and drilling, which isn't going away because I buy a heat pump.

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Although natural gas is "clean" compared to, say, coal, the advantage of a heat pump is that it uses less total energy than natural gas. That means it would be more efficient to run a heat pump off a natural gas power plant than to burn natural gas to heat your home directly.

Where I live, you can bank solar credits. If you cash them out you get the "wholesale" energy price for them (much lower), but if you spend them on electricity then you've avoided paying full price for that electricity. So if your system produces more than you consume, you've got this free energy budget to spend--a budget that applies to heat pumps and not to gas furnaces.

People's AC summertime electric bills regularly get into triple-digits - it's not uncommon to hear someone with a moderately sized home having a $200-400 electric bill in the summertime.

However, even in the midst of winter, gas heating bills rarely climb above $100 monthly.

What am I missing here? It seems a heatpump, while more efficient, will cost significantly more to operate. Natural Gas is cheap... and clean enough.

It's actually difficult to say what the cost would be if everyone switched over. The reason is that natural gas is subsidized, both on the production side (at least in the US, which wants energy security) and on the consumption side (because it's politically unpopular to let people freeze to death). Of course, electricity prices are also affected by subsidies. Figuring out the true operating prices would require some research. However, it remains true that, in terms of greenhouse gas emissions, it is usually preferable to heat a home with a heat pump than by burning gas directly (there exists a temperature below which any given unit will become less efficient than burning gas, but unless you live in a place where this temperature is common then heat pumps will still come out on top (and the fact that residential gas lines are notoriously leaky and basically just venting nonstop into the atmosphere makes the calculation even more favorable)).

It seems to me, there is no future where a heatpump can be the only source of in-home heating then.

1) Natural Gas is vastly cheaper in most/all of the US.

2) Homes still require an alternative heating source when temperatures drop to low levels (coincidentally when people need heating the most).

So, even if a heatpump is technically more efficient in terms of emissions, the technology does not solve all of the problems it's attempting to replace. Additionally, Natural Gas is vastly more clean in terms of emissions than some other alternatives still used around the country.

There's no way the average home is going to stomach 2-4x more heating expenses on average without some real tangible benefit (hand-wavy emissions numbers don't factor into the average homeowner's decision making).

I must be missing something here...

> It seems to me, there is no future where a heatpump can be the only source of in-home heating then. > > 1) Natural Gas is vastly cheaper in most/all of the US. > > 2) Homes still require an alternative heating source when temperatures drop to low levels (coincidentally when people need heating the most).

> ... > I must be missing something here...

Yes you are, your natural gas subsidized, i.e. government handout, i.e. you're not paying the real market cost.

Second, heat pumps do not have issues with cold temps, unless you're at like -40c. They're used all over the nordic countries - including above the arctic circle.

Your energy grid is shit, which is why your electricity price is so high.

> Yes you are, your natural gas subsidized, i.e. government handout, i.e. you're not paying the real market cost.

> Your energy grid is shit, which is why your electricity price is so high.

Adding a heatpump solves this issue, or makes it worse?

Heat pumps power consumption can be modulated by energy providers and improve grid power stability.

In Germany you get way cheaper electricity prices if you allow this.

I am not aware of any such system in the US.

What do you mean by "modulate"? Your utility provider decides how much heat your home gets? That's a very strange concept.

No, they decide how many energy the heat pump currently uses for heating.

That means they control how much heat you get. Otherwise, they would always run in a more efficient/lower-energy demand mode... think about it.

Its only for a restricted time frame

Heat pumps might work at -40c, but all the efficiency gains are lost and it's going to cost a fortune.

The best one reaches 1:1 when approaching -35C, which means that they're as efficient as resistive heaters. So you save nothing in electricity costs, and if all your days are that cold then the $3000 you invested in the heat pump is wasted (that's how much a quality pump with installation will cost you in the Nordic countries - it seems to be much more expensive in North America, at least that's what the comments appear to indicate).

If you have warmer days now and then then you'll start saving money, and eventually it'll pay for itself. Where I live (cold winters), the cost was covered in only two years.

2-4x seems like a stretch, and would only apply in areas with very high electric rates. My last house was heated with a builder-grade heat pump (HSPF around 8), and my winter electric bills were around $150-200/mo. My current house has natural gas heat, and similar level of appliances/EVs/lighting, and winter bills electric bills are around $100/mo. This is the same town and the electric rate didn’t change, so the net cost of heating my old house with a heat pump was only $50-$100/mo. Meanwhile my winter gas bill in this house, subtracting baseline summer usage, runs more than that.

The only backup heat I had with the heat pump was electric resistance heat, which I needed to use only once or twice each winter for a few hours at a time.

You can also use resistive heating (like baseboard heating or space heaters) as a backup for the heat pump when it's too cold out. They're expensive to run off the grid, but if you have solar power and battery storage (for operation at night), they're essentially "free".

Obviously you wouldn't install solar panels and a battery just for this, otherwise it's very much not free, and probably a lot more expensive than burning gas. But if you already have the solar+battery install, and have enough capacity, it could even be cheaper to operate than a gas furnace.

You’re talking about the future but only consider the present. You’re one government decision from your calculation to have an opposite result. Estimating probability of any such decision (ban on fracking, tax incentives, etc) is the hard part.

I'm with you here. I replaced a gas water heater with a hybrid water pump and I'm paying more for my troubles. The thing is, I do plan on installing PV panels in a few years--I can't generate my own gas so once I make that happen, I'll be a happy camper.

That was my plan; install solar panels and then slowly switch things from gas to electric as they need replacement. Unfortunately solar installer I was in contract with canceled on me for seemingly-bogus reasons, and I didn't have time to find a new one before California's new, unfavorable net metering rules went into effect.

Most hybrid water pump heaters do not fully use their heat pump by default - their should be an "Eco" or "heat pump only" setting somewhere on your device which will make it much more efficient.

I'm fairly certain we're near - or even past - the point where burning natural gas to run a generator to power a heat pump will use less gas than burning the gas directly for heat.

Perhaps you live in a warm climate? A heatpump (or heatpump + gas for a very cold climate) should cost always cost less than gas

Replaced our entire system (furnace, a/c) mid last year. Heat pump with backup oil for colder days.

We cut the amount of gallons we used by over 50% compared to last year. Sure the oil infrastructure is needed to get it delivered (I wish we didn't need it) but I'm very happy that our heating (oil+electricity) bills are so much lower, even with the increased oil prices.

We went with a mid-range system but now I kind of wish we sprung for the "Cadillac" version.

I suppose this would be true if gas is expensive where you live. It's really cheap here, our heating bill is like $80/mo in the coldest of months for a 3k sq ft house. A heat pump even with the efficiency gains would be on par with that (unless we jumped into solar, which I have considered).

You need a backup heat source, but it doesn't necessarily mean you need full infrastructure of gas lines, ducting, and gas furnace. You could have an electric backup connected to ducted heat pump (e.g., non-efficient, pure electric) or could use electric strip heating, electric portable heaters, wood stoves, etc.

We have electric baseboard. It would cost hundreds more per month to utilize something like that instead of gas when it is -30F. In fact if we just leave it on over night a single time we notice it on our bill.

They make heat pumps with backup gas systems now.

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