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Heat pump users noticing cheaper bills and warmer homes – study

theguardian.com

11–20 of 113 posts

Re: Heat pump users noticing cheaper bills and warmer homes – study

#11

The headline doesn't match the article: of the three people interviewed, the first loved it, but taxpayers paid for hers. The second liked it, but doesn't know if he'll ever make the money back, and the third didn't like it.

We recently replaced our old leaking big-ass-tank gas hotwater service with a continuous flow gas system.

I looked into heat pumps, but cost the of the device + installation + an electrician to run a new line (seemed that would be needed) ... I dont think it was ever going to break even over the rated life span of the system. The cheap ones were still 3 times the price of a gas system, just for the hardware. That and I would have to buy the heatpump from out of town, so getting any warranty/servicing might be more drama. And I really didnt want to listen to a cheap compressor tick-on all the time.

Another sad mark in the "wish I didnt have to kill the planet but ..." column. Feels like a rich mans game.

Re: Heat pump users noticing cheaper bills and warmer homes – study

#12
I (self installed) a heat pump and I love it.

Sure, it's not really efficient (COP ~1.5) when it's -10C outside, but this happens 1 day per year. Most of the time the COP is around 4: that means that it uses 1kWh of electricity to produce 4 units of heat. My electricity kWh is .17cts, so the final heat kWh is ~ 0.17/4 = 0.04cts, which is awesome.

Using france's electricity production mix, that means that I can heat my house for 60/4 g/kWh = 15gCO2/kWh.

Re: Heat pump users noticing cheaper bills and warmer homes – study

#13

The headline doesn't match the article: of the three people interviewed, the first loved it, but taxpayers paid for hers. The second liked it, but doesn't know if he'll ever make the money back, and the third didn't like it.

We recently replaced our old leaking big-ass-tank gas hotwater service with a continuous flow gas system. I looked into heat pumps, but cost the of the device + installation + an electrician to run a new line (seemed that would be needed) ... I dont think it was ever going to break even over the rated life span of the system. The cheap ones were still 3 times the price of a gas system, just for the hardware. That and…

> Another sad mark in the "wish I didnt have to kill the planet but ..." column.

The high cost of the hardware, installation and maintenance suggests that you would rather "kill the planet" with the system installed?

Re: Heat pump users noticing cheaper bills and warmer homes – study

#14
post #10
post #5

I thought this was a new kind of air-source heat pump without all the problems of existing ones, but no, it's just a heat pump. Inappropriate for many (possibly most) dwellings in the UK, and the government is bribing people to install them. For what it's worth, I think systems like https://www.tepeo.com/the-zeb will eventually replace gas in the UK, not ASHPs. Similar technology is being trialled at some army barrac…

> Inappropriate for many (possibly most) dwellings in the UK Why ? UK is well above freezing (and even them, heat pumps _work_ below freezing, even with a COP > 1). So I'm curious about your assumption

I expect it's more to do with how poorly insulated most UK homes are

Re: Heat pump users noticing cheaper bills and warmer homes – study

#15
post #10
post #5

I thought this was a new kind of air-source heat pump without all the problems of existing ones, but no, it's just a heat pump. Inappropriate for many (possibly most) dwellings in the UK, and the government is bribing people to install them. For what it's worth, I think systems like https://www.tepeo.com/the-zeb will eventually replace gas in the UK, not ASHPs. Similar technology is being trialled at some army barrac…

> Inappropriate for many (possibly most) dwellings in the UK Why ? UK is well above freezing (and even them, heat pumps _work_ below freezing, even with a COP > 1). So I'm curious about your assumption

The OP did a bad job but here are my guesses.

Most traditional UK homes do not have central air, they use boiler/radiator systems for the winter. Retrofitting these homes do have central air with a heat pump probably does not make sense.

I don't think the product the OP linked was a very good example either. It's just an electric boiler that somehow stores offpeak energy to be used during the day. Don't know a lot about boiler systems but I cannot imagine these are that revolutionary and there are other similar systems out there, it is just an electric boiler with a smart energy/battery storage system to capture the off peak energy...seems like you could do something similar with a standalone electric boiler and a battery backup system.

Re: Heat pump users noticing cheaper bills and warmer homes – study

#16
post #7

Heat pumps could actually lead to a net increase in energy usage in northern areas because they can double as air conditioners for cooling in the summer. Normally homes in northern areas don't have AC and you just have to get through the relative short period when its hot enough that it would be nice to have. But with heat pumps, you just switch to AC mode. Also, those periods of hot weather are getting hotter and lo…

But demand is lower in the summer, so this shouldn't effect renewable energy requirements.

This is regionally specific. The US south, for instance, sees higher usage in summer due to air conditioning demand.

Re: Heat pump users noticing cheaper bills and warmer homes – study

#17

Heat pumps could actually lead to a net increase in energy usage in northern areas because they can double as air conditioners for cooling in the summer. Normally homes in northern areas don't have AC and you just have to get through the relative short period when its hot enough that it would be nice to have. But with heat pumps, you just switch to AC mode. Also, those periods of hot weather are getting hotter and lo…

[deleted]

Re: Heat pump users noticing cheaper bills and warmer homes – study

#18
post #7

Heat pumps could actually lead to a net increase in energy usage in northern areas because they can double as air conditioners for cooling in the summer. Normally homes in northern areas don't have AC and you just have to get through the relative short period when its hot enough that it would be nice to have. But with heat pumps, you just switch to AC mode. Also, those periods of hot weather are getting hotter and lo…

But demand is lower in the summer, so this shouldn't effect renewable energy requirements.

This is a good point, summer time could potentially use solar.

Re: Heat pump users noticing cheaper bills and warmer homes – study

#19
post #15
post #10

Earlier quoted context omitted.

> Inappropriate for many (possibly most) dwellings in the UK Why ? UK is well above freezing (and even them, heat pumps _work_ below freezing, even with a COP > 1). So I'm curious about your assumption

The OP did a bad job but here are my guesses. Most traditional UK homes do not have central air, they use boiler/radiator systems for the winter. Retrofitting these homes do have central air with a heat pump probably does not make sense. I don't think the product the OP linked was a very good example either. It's just an electric boiler that somehow stores offpeak energy to be used during the day. Don't know a lot ab…

Heat pumps work perfectly fine with radiator systems.

Re: Heat pump users noticing cheaper bills and warmer homes – study

#20
post #4

The headline doesn't match the article: of the three people interviewed, the first loved it, but taxpayers paid for hers. The second liked it, but doesn't know if he'll ever make the money back, and the third didn't like it.

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.

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.
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