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How a heat pump works

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Re: How a heat pump works

#71

Post by PragmaticPulp »

bcrosby95 wrote: post #64
Maxburn wrote: post #33

Earlier quoted context omitted.

YES. There is a massive electrification push right now because electric items can be fed from "sustainable" things like wind/dam/solar and don't emit CO or CO2 in operation. Heat pumps are also inexpensive on initial cost and less expensive than straight AC with gas heat. They are also low maintenance in comparison to straight AC with gas heat. Very popular units in southern US.

This hasn't been my experience. I can get an AC unit and gas furnace installed for something like 7k. But a heat pump unit that heats and cools is something like 13k installed. I obviously went with the former.

The install price is only the start. The total cost of ownership over expected lifetime is the important number for many. That initial 7K installation cost is only a fraction of what you’re going to pay in gas and electricity over the next decade.

Re: How a heat pump works

#72

Post by rcme »

suoduandao2 wrote: post #24
kzrdude wrote: post #10

Earlier quoted context omitted.

Who do you imagine is pushing, and why? Don't you want to resist to turn to explanations like this, that require some invisible force to pull the strings? I think there are more realistic ways to imagine this happening. If for example a pop star is getting a lot of attention, in multiple countries, what is the mechanism behind that? And is it orchestrated?

Explanations like what? Op didn’t put forward much in the way of hypotheses. If you have a good explanation of the mechanism by which attention accumulates around topics that doesn’t require orchestration it would be interesting to hear, it seems like a poorly understood phenomenon.

It’s called: product market fit. When people like your products, they talk about them.

I have heat pumps through a mini split system. I like them so much I’m redoing my entire HVAC to add ducts with heat pump powered heating and AC. They’re kind of a miracle: they produce great heat (way better than a gas-powered furnace), they’re ultra-efficient, and they’re whisper quiet.

Re: How a heat pump works

#73

Post by asow92 »

prottog wrote: post #57
asow92 wrote: post #49

As someone who lives in the northeast and has a 3600sqft home, I'm wondering how many heat pumps it would take to replace my gas steam boiler system. I'm not sure if heat pumps would be cost efficient given those parameters.

In the Northeast with that much square footage, you would be better off with ground-source heat pumps (whether open or closed loop), rather than the normal air-source heat pumps.

I guess the concern I have with all this is that my current system works well, and I don't want to spend $10K+ unless it brings down my heating costs significantly. Could a ground-source heat pump system do that?

Re: How a heat pump works

#74

Post by Maxburn »

bcrosby95 wrote: post #64
Maxburn wrote: post #33

Earlier quoted context omitted.

YES. There is a massive electrification push right now because electric items can be fed from "sustainable" things like wind/dam/solar and don't emit CO or CO2 in operation. Heat pumps are also inexpensive on initial cost and less expensive than straight AC with gas heat. They are also low maintenance in comparison to straight AC with gas heat. Very popular units in southern US.

This hasn't been my experience. I can get an AC unit and gas furnace installed for something like 7k. But a heat pump unit that heats and cools is something like 13k installed. I obviously went with the former.

That's fascinating and I believe you were subject to some weird market conditions there. Look at the complexity of gas burners vs a reversing valve and electric heat strips and I think you will see what I mean.

Re: How a heat pump works

#75

Post by PragmaticPulp »

redeeman wrote: post #44
boringg wrote: post #7

What is going on? Is there a global push to get everyone to switch to heat pumps. It seems that there is heat pump content everywhere. Clearly there is a push. I understand that its for climate benefits but it feels very coordinated. edit: didn't realize the attention I would get. Let me add someone answered my question -- a good product market fit and people talking is probably where the push came from. That said HV…

topic of discussion: is anyone else concerned that all the new things being clearly pushed hard, regardless of reasons(good or bad), has the common theme of centralizing. In a world where if your heatpump stops working, you die from cold, it would be an awfully sad thing if social credit scores dictated a very low kilowatthour limit. Much more sad than a world where you obtain firewood from some local vendor

> has the common theme of centralizing. In a world where if your heatpump stops working, you die from cold,

Using machinery for heating isn’t new. Virtually nobody in the modern world uses firewood from a local vendor to heat their homes.

These conspiracy theorist angles are baffling. Heat pumps are just another variation of AC, which is already ubiquitous. If people don’t use heat pumps, they won’t use firewood. They’ll use a regular furnace or electric heat.

Re: How a heat pump works

#76

Post by Maxburn »

PragmaticPulp wrote: post #71
bcrosby95 wrote: post #64

Earlier quoted context omitted.

This hasn't been my experience. I can get an AC unit and gas furnace installed for something like 7k. But a heat pump unit that heats and cools is something like 13k installed. I obviously went with the former.

The install price is only the start. The total cost of ownership over expected lifetime is the important number for many. That initial 7K installation cost is only a fraction of what you’re going to pay in gas and electricity over the next decade.

Very true. Simply having gas available to use results in a base bill for service, even if your usage is zero.

And yet what I see time and again is that initial purchase price is the only focus for construction costs, even rehab work. Those budgets are a separate bucket from utility bills so lower priced projects get approval even if utility bills will be higher.

Re: How a heat pump works

#77

Post by mytailorisrich »

wongarsu wrote: post #27
boringg wrote: post #7

What is going on? Is there a global push to get everyone to switch to heat pumps. It seems that there is heat pump content everywhere. Clearly there is a push. I understand that its for climate benefits but it feels very coordinated. edit: didn't realize the attention I would get. Let me add someone answered my question -- a good product market fit and people talking is probably where the push came from. That said HV…

For a long time the main problem of heat pumps was that while they are more efficient, a kilowatthour of gas or oil is much cheaper than a kilowatthour of electricity. But in the last two years natural gas prizes have gone crazy, removing that price disadvantage. Of course heat pumps emitting no particulates and being able to run on renewables are also good reasons, especially as the health impact of living in cities…

It's not directly related to the recent spike in prices, especially considering that a heat pump installation is very expensive in itself and potentially disruptive.

Rather, it's a combination wanting to get to net zero, so no emissions, with the big problem of generating enough green electricity. A heat pump system has no emissions and consumes much less electricity than an electric boiler/electric heater.

Re: How a heat pump works

#78

Post by fullstop »

bcrosby95 wrote: post #64
Maxburn wrote: post #33

Earlier quoted context omitted.

YES. There is a massive electrification push right now because electric items can be fed from "sustainable" things like wind/dam/solar and don't emit CO or CO2 in operation. Heat pumps are also inexpensive on initial cost and less expensive than straight AC with gas heat. They are also low maintenance in comparison to straight AC with gas heat. Very popular units in southern US.

This hasn't been my experience. I can get an AC unit and gas furnace installed for something like 7k. But a heat pump unit that heats and cools is something like 13k installed. I obviously went with the former.

How long do those units last, though, and what is their operating cost over their lifetimes? TCO obviously includes more than the initial cost of the equipment.

Re: How a heat pump works

#79

Post by slfnflctd »

fullstop wrote: post #45
notdarkyet wrote: post #34

Earlier quoted context omitted.

I see this as well and it looks to be multiple people buying in to the campaign, especially here on HN. Having lived in a new, high end apartment that had a heat pump for both heating and cooling for 3 years, I am very unimpressed with the tech. Running nonstop, couldn't heat/cool above/below a certain threshold. Electric bill very high. Clogged and broke a lot. If the general radiant heat and cooling from being in l…

Your high end apartment must have had a low end heat pump installed. In the midwest a geothermal heat pump would work wonderfully. Also, they are designed to run constantly in order to maintain the set temperature -- it's not like a natural gas fired furnace where it quickly reaches the set point.

What's the payback time on something like that for a modest home in a place which can get significantly under 20 degrees (F) or over 95 degrees for weeks or longer? How effective is it at those extreme temperatures when it matters the most, and how does this affect maintenance costs?

Additionally, there are multiple types of restrictions on where geothermal pumps can be installed, and navigating this can add to costs.

I don't see it as a one size fits all solution, there are far too many people for whom the household/company math doesn't add up. However, I agree we should be doing fair comparison against other renewable-friendly options for all new construction. I'm sure heat pumps could win out in a great many situations, and we should use them where they do.

Re: How a heat pump works

#80

Post by aliqot »

vintermann wrote: post #38
nicoburns wrote: post #9

Earlier quoted context omitted.

> Is there a global push to get everyone to switch to heat pumps. I mean, yes. They're much more energy efficient than the alternatives and will play a key part of removing our dependence on fossil fuels. > I understand that its for climate benefits but it feels very coordinated. That seems like a good thing?

Yeah. If some people came together at Davos or whatever and decided "we need to promote heat pumps!", you can be sure they would mess it up. Consent can maybe be manufactured. Enthusiasm is organic, for good and bad.

It's like you got to the endzone and fumbled with <5yds
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