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Comment by starbugs | Hacker News Reader

This (at least the headline) reads like an advertisement for heat pump systems.

I doubt that anyone has calculated the total cost of owning and operating such a system. It might pay off in a super modern highly insulated home. Otherwise, good luck with these systems. The high upfront and maintenance cost and the expected lifetime of about 15 years make this look like a very questionable proposition to me.

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Why do you doubt anyone has calculated the total cost of owning and operating such a system? I bought and paid for two heat pumps twelve years ago and the reduction in energy costs resulted in them paying for themselves after 11 years. The cost of ownership was simply the purchase and installation cost as I did not take out a loan or receive any government funding. There was virtually no maintenance required except cleaning the humidity drain half a dozen times. Right now I'm waiting to see how long they last before they fail so I can calculate the total amount of savings. I should also point out that because my heat pumps are 12 years old, they only have a CoP of 3, while new heat pumps have a CoP of 4 and it is expected units with a CoP of 5 will be available within a few years.

+ it adds to the cost of new developments in the countries where its mandatory a high efficiency rating, like Ireland BER

https://www.seai.ie/home-energy/building-energy-rating-ber/

https://www.gov.ie/en/publication/1ca53-new-energy-efficienc...

By the way there's talk from some gov officials to forbid selling old houses if the BER rating is too low. You will need to spend thousands to get it to some better rating.

Listed houses should get an exemption to install double glazed windows and other insulation upgrades. Or they should get a discount on energy costs.

Or get subventions for insulation upgrades?

The climate in the UK may be too warm to see the real benefits. Heat pumps have been popular in the Finland for 15+ years. The calculations vary from situation to situation, but the rule of thumb is that the initial investment pays itself back in ~5 years, and you have to replace the heat pump after ~15 years.

5 years look for me highly unexpected. Can you please detail the pump type and whether you get subventions for it?

This number is more or less the same in Norway as well for air-to-air pumps without subsidies. Keep in mind that oil/gas heating and such is not normal, we've used electricity and firewood for heating for the most part. So replacing electric heaters with a heat pump will drastically reduce electricity costs, improve air quality and improve heating. Really a no brainer.

Ok that makes sense then. Most people here will compare against an existing gas or oil heating installation I guess...

That's what news articles and the companies installing heat pumps have been saying since ~2005. Had those estimates been substantially wrong, we'd know it by now.

The only subsidy is the deduction for hiring household help. If you hire outside help for any purpose, you get a tax deduction based on the wages you pay.

Why is it so expensive to set up? Air conditioning seems to be everywhere in Asia and insulation is basically nonexistent

No clue. The last time i looked, the prices for a heat pump from known companies like LG or viesmann are similiar than a gas burner.

And with a heat pump you can even invest in PV and use that to be even more independent and later you can leverage an EV car either by never buying gas again or for storage.

Overall a very smart concept.

But perhaps he lives in a country were energy is very cheap, will stay cheap and is very stable?

I think the answer depends largely on the retrofitting cost, then less so on local market conditions. I.e. a niche market has fewer trained technicians and higher margins.

But the retrofitting issues can be substantial, particularly when it triggers updated building code enforcement. An older house with natural gas heating and no air-conditioning may need major electrical upgrades to support a heat pump system. Others may require ducts to be replaced. Or, other invasive work to meet newer insulation standards. Some houses might have some fluid-based radiant heating and require rework because it was designed for the higher fluid temperatures of a boiler while a heat pump system would use lower temperatures and higher flow rates.

Also, many homes may be subject to some kind of aesthetic rules which rule out the mini-split systems popular in Asia. The owner cannot just bolt new equipment or conduits to the exterior of the house. Instead, the above retrofitting tasks turn into major renovation jobs to tear apart interior walls.

We did, or rather received such calculations from the providers. Today and here, depending when you retire and what your plans after that are, you might think twice about getting a geothermal one. The air-water would fit as the 1:1 replacement for the oil heating we have, with the promise of barely breaking even. NB: when you replace/upgrade an existing pump, some costs won't come again.

> We did, or rather received such calculations from the providers.

Well, the calculations from the providers are highly likely to be "optimized". I would suggest the first point one might check is if the given COP is realistic. Usually it isn't.

Wouldn't it take longer to pay off on a well-insulated home? That's the sort of home that doesn't use much gas to begin with.

1) Good insulation means you can use a smaller (cheaper) heat pump. Or it doesn't need to work hard most of the time & is therefore likely to last longer.

2) Having that heat pump removes the need for a natural gas hookup - and fixed-rate monthly cost that comes with it regardless how much gas is used.

Of course, you can't save what you don't spend ;) A very well insulated home can rely on only a heat pump.

In germany this topic was disucssed and is still discussed up and down and a TON of studies and caclulations exists.

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