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Heat Pumps – The Well-Tempered Future of A/Cs

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Re: Heat Pumps – The Well-Tempered Future of A/Cs

#161

Post by thsksbd »

triceratops wrote: post #122
wcfields wrote: post #55

Earlier quoted context omitted.

Have to imagine that the niche market for making 40F/4C "cold" water from luke-warm tap water (if you live in an area that is so hot the tap water is warm) is fairly small.

It's not a niche market. Every office in the world has a water cooler. The market for evaporative water coolers is niche, or probably only big in the developing world. Other than that water coolers use refrigeration aka a heat pump.

Naw. Every office in the world has a water dispenser misnamed "cooler".

Ive only ever seen water coolers in the US, mainly in the South, and they're loud

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#163

Post by bfuller »

web3-is-a-scam wrote: post #130

My 20 year old air conditioner recently died and I was looking into replacements. In my climate the temperature ranges from 40C in the summer, and -40C in the winter. After doing some research, it seemed pretty clear that having a furnace+AC was the way to go for my climate. Hardly a magic bullet technology.

Heat pumps require more specialized techs to work on them too.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#164

Post by cwkoss »

zamalek wrote: post #155
pdx_flyer wrote: post #152

I was looking for a whole home heat pump and got some quotes that started at $27,000 for a home that is 1800 square feet. That price is a bit hard to swallow. I really don't want to just cool one or two rooms in the house.

Are you sure you aren't getting quotes for a ground-sourced (AKA geo) heat pump? We just installed a 4.5 ton (overkill for your sqft) 20 seer unit for $18000.

I got a very similar quote ($27k for ~2000sqft home) in seattle a few months ago.

Salesperson said there is excess demand for both labor and machinery for heat pump installations in the past few months. I wondered at the time to what extent this is a regional phenomenon (seattlites are nerds who like energy efficiency) vs. supply chain issues vs. a sales technique.

Interestingly, I learned that it will be too cold for heat pumps <10 days out of the year, so most people either keep their gas furnace as backup, or install an electric furnace for these rare days.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#165

Post by Casteil »

web3-is-a-scam wrote: post #130

My 20 year old air conditioner recently died and I was looking into replacements. In my climate the temperature ranges from 40C in the summer, and -40C in the winter. After doing some research, it seemed pretty clear that having a furnace+AC was the way to go for my climate. Hardly a magic bullet technology.

Similar climate here, although days it gets below -10f / -23c are uncommon. Most winter days in a climate like this you could heat with a modern/high tech heat pump, but:

- It's probably going to be more expensive than heating with natural gas if you're in the northern US - at least as things are today.

- A modern/high tech heat pump capable of heating when the outdoor temp is - A natural gas furnace can keep you warm (and keep your pipes from freezing/bursting) even if there's a power outage. It doesn't take much of a generator to run a furnace/blower fan.. but good luck staying warm with ONLY a heat pump in those circumstances.

The one thing that can really help improve the financials of getting a heat pump is if you intend to install solar power at some point in the future. Depending on your power company, you may be able to generate enough credit in summer with excess generation to pay for heat the entire winter. I'd still go with a heat pump AND gas furnace for backup though.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#166

Post by bfuller »

Alupis wrote: post #140
kevin_thibedeau wrote: post #111

Earlier quoted context omitted.

It's being driven by government pressure to reduce energy consumption and dependence on fuel imports. That isn't a bad thing. It's the sort of thing a responsible government should be planning for.

Natural gas is available in abundance, is nearly free in terms of cost, and is vastly more "green" than many alternatives available today. It may not be as green as pure electric can be in theory, but in large portions of this country electric isn't all that green either. Heat pumps appear expensive to operate. Imagine running your AC year-round... that very thought makes many-a-homeowner shudder.

Heat pumps are expensive to operate, and a nightmare to fix. There is a big movement to build whole subdivisions without using natural gas at all, electric ranges and heat pumps. I don't know why it upsets me so much but it does.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#167

Post by triceratops »

mindslight wrote: post #123
triceratops wrote: post #85

Earlier quoted context omitted.

> Heating is considerably more energy efficient than having to run ACs all over the place. That's actually incorrect. Heating takes considerably more energy. When you're cooling you're looking at a temperature delta of at most 20 degrees C/45 degrees F between outside and inside. When you're heating, it can be easily be twice that. Or even more, in parts of Canada or the Great Lakes states. Air conditioning is a heat…

> Air conditioning is a heat pump and can achieve up to 300% efficiency. Whereas most houses in cold climates use furnaces, which have at most 98% efficiency. No. You can't directly compare "efficiency" numbers across different energy sources. My understanding is that the efficiency of gas powered electricity generation is around 33%, meaning that powering a heat pump with a COP of just under 3 will be of similar end…

End-to-end efficiency calculations are tricky and depend on a lot of variables.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#168

Post by hedgehog »

cwkoss wrote: post #164
zamalek wrote: post #155

Earlier quoted context omitted.

Are you sure you aren't getting quotes for a ground-sourced (AKA geo) heat pump? We just installed a 4.5 ton (overkill for your sqft) 20 seer unit for $18000.

I got a very similar quote ($27k for ~2000sqft home) in seattle a few months ago. Salesperson said there is excess demand for both labor and machinery for heat pump installations in the past few months. I wondered at the time to what extent this is a regional phenomenon (seattlites are nerds who like energy efficiency) vs. supply chain issues vs. a sales technique. Interestingly, I learned that it will be too cold fo…

Getting anything at all done in the Seattle area is super expensive. Not sure why. The rep is wrong about the too cold bit though, even just what's in stock at Lowe's is rated to well below record lows for the region.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#169

Post by IanCal »

1-more wrote: post #47
Maxburn wrote: post #23

Earlier quoted context omitted.

It's an industry term for mechanical equipment that can heat AND cool. One piece of equipment replaces your AC AND heat source. Heat pumps in particular are getting a push from "green" initiatives because they only use electricity for fuel which can potentially be supplied by "renewable" sources. ie; it's a buzz word.

> because they only use electricity for fuel which can potentially be supplied by "renewable" sources. They also can operate at >100% efficiency. Under the right conditions (I'll let someone who knows more about it fill that in) they can provide more heat than the same amount of power going into a resistive heater (which is I think per-se 100% efficient right?). Kinda wild.

This should happen under a fairly wide range of temperatures for modern heat pumps. Quoted figures are usually in the 3-4x more efficient than resistive heating when adjusted for seasonality for air source heat pumps. Ground source are more like 5+ I think.

That's lab figures though so I guess similar to car efficiency figures.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#170

Post by loeg »

web3-is-a-scam wrote: post #130

My 20 year old air conditioner recently died and I was looking into replacements. In my climate the temperature ranges from 40C in the summer, and -40C in the winter. After doing some research, it seemed pretty clear that having a furnace+AC was the way to go for my climate. Hardly a magic bullet technology.

Most people live somewhere with vastly milder winters. Generalizing from your -40C winters is not useful.
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