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Heat pumps of the 1800s are becoming the technology of the future

knowablemagazine.org

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Re: Heat pumps of the 1800s are becoming the technology of the future

#421

Post by xpe »

retrac wrote: post #2

> heat pumps: electrical devices Just to be pedantic, but not exactly. The typical design in a domestic heating unit, or refrigerator is mechanical. A fluid is pumped and cyclically compressed/expanded. While electric motors are usually used, they can be driven by any source of mechanical energy; driven directly by a combustion engine is not too unusual. There are also heat pump cycles that can be driven directly wit…

TLDR: for a heat pump, "electromechanical device" is more descriptive than "electrical device"

Re: Heat pumps of the 1800s are becoming the technology of the future

#422

Post by jillesvangurp »

phyzome wrote: post #144

> owners of drafty homes may need to take on the added cost of insulation when installing a heat pump Installing good insulation is also really important even if you're not using heat pumps! With bad insulation, you're wasting energy no matter what technology you're using.

Also, you can use heat pumps with poor insulation just like you can use traditional heating solutions with poor insulation. It's just that you will need a larger system that wastes more energy. Whether that's still worth the trouble in terms of cost of course depends on your current situation of course.

But it's not like heat pumps stop working because of your insulation. They just get more costly to operate. And especially the smaller systems can only deliver so much energy to your house. Basically, if you multiply the maximum output by three, that should be above whatever you are currently using to heat your house during a really cold month. If it's lower, it's not big enough.

Re: Heat pumps of the 1800s are becoming the technology of the future

#423

Post by danuker »

lll-o-lll wrote: post #349
danuker wrote: post #319

Earlier quoted context omitted.

My soul abhors waste and enjoys comfort. I would feel terrible either knowing I'm wasting half my heating energy, or freezing in my home.

Warm climate, remember? If you cannot cope with an ambient temperature that drops below 20C, there is this thing called “radiant heat”. You can make it with fire. Also, relatively small amounts of electricity. Radiant , just like your soul would become.

Ah. Apologies. But the same is true for cooling. I can't work if it's hotter than 26C.

About radiant heat: it is nowhere near the comfort of uniform whole-room heating.

Re: Heat pumps of the 1800s are becoming the technology of the future

#424

Post by dghughes »

I'd prefer a heat pump that uses ducts I hate the look of ductless heat pump that giant eyesore lump on the wall.

But ducted are not as efficient compared to ductless due to the long runs of ducts and cold attics (even if ducts insulated). Plus my province won't give any rebates for ducted only ductless.

Even better would be ground-source heat pump. But still I'd prefer ducts I think you'd have to with a ground source system.

Re: Heat pumps of the 1800s are becoming the technology of the future

#425

Post by realityloop »

fifteenforty wrote: post #109

In a house I own in Melbourne, Australia, I just replaced an old gas central heating system with 3 new top of the line Daikin mini split heat pumps. The new units can heat the entire house for the same amount of electrical energy that was used to run the FAN in the old gas unit. They are crazy efficient. Ducts are dead. The Daikin Alira X is the gold-plated option and cost $8k AUD for 2x2.5kw and 1x7.1kw units includ…

Which side of the city are you on, could you let me know who you had do the installation please?

Re: Heat pumps of the 1800s are becoming the technology of the future

#426

Post by pbhjpbhj »

thadk wrote: post #289
jwcooper wrote: post #148

Earlier quoted context omitted.

Where I live, it can get very cold. Not always very efficient to open windows for 5 months out of the year. A great option for keeping CO2 levels down in a house is with an HRV (or ERV) [1] that will heat the fresh air coming in to cycle it throughout the house. [1] https://en.wikipedia.org/wiki/Heat_recovery_ventilation

There is an open source 3D printable unit design here which I installed in my window and works well for relatively efficiently exhausting the CO2 from one person in cold weather: https://www.openerv.org (license: CC BY-NC-SA 3.0) I did not 3D print mine, but ordered it, though as an early adopter, adjustment was required.

Do you know, is there a document explaining the design somewhere? I can see from the Google images some of the parts, but not clearly all the parts nor the flowpaths and such.

Re: Heat pumps of the 1800s are becoming the technology of the future

#427

Post by 2rsf »

nemo44x wrote: post #171
poutine wrote: post #53

Earlier quoted context omitted.

Living in the PNW, I'm building a new house and I've chosen a dual fuel hybrid heat pump system as per https://www.bryantbing.com/products/hybrid-heat/ I'll also have solar + battery. Should be able to run the furnace & fan but not the heat pump (too many kW/h) during a power outage and thus heating with gas. It'll run off the heat pump for 90-95% of the year, only using gas on the coldest days, or during an outage.…

Why not install heated floors? That would be my choice in a new build.

Why? heated floor are a little more efficient in heating and for some are a little more comfortable, but from my experience they are also slow to react so it's harder to control the temperature when the weather changes daily for example in the spring or automn.

Re: Heat pumps of the 1800s are becoming the technology of the future

#428

Post by 2rsf »

PinguTS wrote: post #49

Sorry, but I don't see any novelty here. Everything described in the article is commercially available. At least here in Germany. Heat pumps are used to heat a storage container called buffer, a water container of 200l or more of water. This is used to run the heat pump when energy is cheap to warm up the buffer. That is for example in daytime when energy is available from the photovoltaic. If you don't have photovol…

How big should the tank be? Googling a little shows that it should usually be a small lake size or a big pond, not something you put in your yard.

Re: Heat pumps of the 1800s are becoming the technology of the future

#429

Post by 2rsf »

macinjosh wrote: post #27

Half way through the article the author is touting how these can work in cold climates like Norway, then their example homeowner immediately states they have this but also they still have a furnace for when it actually is cold. Why do journalists try to pull crap like this? Contradictory information in the same paragraph!? If you have to have a backup it is _not_ a replacement and it will not get us off of carbon. Mo…

Here in Sweden your backup system could simply be a fireplace, at least if you refer to extra heating and not for cases of power failures.

This works great since all houses, including those 100 years old, are well insulated.

Re: Heat pumps of the 1800s are becoming the technology of the future

#430

Post by elil17 »

sidewndr46 wrote: post #329
elil17 wrote: post #169

Earlier quoted context omitted.

It's not about fault at all - I'm just saying that the analysis does not apply to lightbulbs. For a lightbulb to be as efficient as a resistance furnace at heating a room, you would need to have zero light escape that room so that all the light would be converted to heat. Then, the heat would leave the room at the same rate as heat generated by a resistance furnace. Even if we consider incandescent light bulbs, which…

You do realize that burning natural gas for heat produces light as well right?

Natural gas furnaces are designed to not let that light out. Instead, the light is absorbed by the surfaces of the furnace and turns into heat. The inefficiency in gas furnaces is heat leaving in the exhaust.
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