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Comment by dgllghr | Hacker News Reader

Does electric heat mean heat pumps or radiant? Because we have saved a bunch of money switching our heat from natural gas to heat pump

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> One issue in the debate is that "electrification" doesn’t mean the same thing to everyone. For one thing, the definition of “using electricity to heat their homes” used by the federal energy office appears to mean the use of electrical resistance baseboard heating versus natural gas heated-air furnaces.

> But, in the Energize Denver initiative, city officials are talking about heat pumps versus gas furnaces, which means a different set of cost calculations.

the report is from the US Energy Information Administration

It's buried in the article, but the 77% number seems to be based on resistance heating instead of heat pumps:

> the annual energy bill to operate a standard gas furnace/AC combination is about $633 a year. With a heat pump, she said, it would likely be $609 to $718 annually, depending on the heat pump technology chosen and its configuration.

But, to be fair, the first sentence of the article is "The average American household that uses electricity to heat a home this winter will pay hundreds of dollars more than those who use natural gas." How many households have heat pumps, vs how many have old electric baseboards? I think it's entirely appropriate for a government report to be looking at the actual costs to households today. If most American's can't handle a $500 surprise expense, how many can afford to upgrade to a heat pump? And 35% of Americans rent -- how many old neglected apartments have electric heat which the landlord has no incentive to upgrade?

It really sucks because even with the government rebates, it’s still a big capital expense that takes years to be paid back. The good news is that since we have started investing in and incentivizing heat pump technology now, it will be the cheap option as heating systems fail over the next few decades. I think the government report should include this reality but also highlight heat pump adoption as it is currently incentivized and adoption is growing. It’s weird to me that they didn’t highlight the heat pump aspect as much

I just heard on NPR yesterday that 13% of all house sales last year were new construction. As much as I am loath to have stringent regulations dictating building technology, just imagine the pace of adoption if every piece of new residential construction used electric air-source heat pumps.

> The good news is that since we have started investing in and incentivizing heat pump technology

Yes, good tax news for those who own their house and can afford discretionary purchases. Also good news for those who peddle increased govt debt.

Described differently, heat pump and ElectrifyTodayCorp lobbyists had Congress write tax incentives for their businesses which are funded by taxes on working class that are renters or can't afford to replace their existing functional furnace.

Are these tax credits meant to encourage people to replace functional equipment with different types, or are they meant to encourage people to replace broken equipment with a different type? (Or to encourage new construction to use a different type than typical)

Often, for light users, the payback time for switching to a more efficient heat system is longer than the expected lifetime of a new system, so it only makes sense to consider it when the current heating system is broken or when the current cooling system is broken, since a new heat pump could replace heating and cooling.

It's potentially different if you're a heavy user of heating.

Heat pumps will never be a viable replacement because they only work efficiently at low heating temperatures. The heat pump itself may cost you 5 to 10k but you may have to spend another 50-100k on insulation of walls, windows, roof, basement as well as floor heating (and thus completely new flooring) in every room to make it work. This is doubly true in the US where many buildings still have single-pane windows (though you have the advantage of not paying 40c/kWh like we peons in Germany).

And btw: heat pumps are loud, so good luck with that high density housing every climate advocate wants so much.

It depends on the ambient temperature. Heat pumps can obtain a coefficient of performance of about 2.5 in very cold conditions (-20 C) or as much as 5 in warmer conditions (+5 C).

In theory, you could get even better performance by using a heat pump during the day to melt calcium chloride hexahydrate (mp 29 C = 84 F), and then freezing it at night to recover the stored energy. But now your system cost is even higher, since you need a ton of calcium chloride.

The article addresses that

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