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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

#271

Post by JenrHywy »

lll-o-lll wrote: post #192
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.

If you live in a warm climate, I personally think insulation is the worst (excepting roofing). Not because of efficiency, but because you isolate yourself from nature! The traditional Queenslander (look up Bluey if you don’t know what I mean), has so much going for it. It allows airflow through the whole house, a protected outside to sit and be with nature, lizards coming and going, bliss! This hermetically sealed en…

Queenslanders work fine in Queensland, where the lows in winter are still double-digit C. Most of the world (or even Aus) isn't like that. A Queenslander in Canberra would have a massive heating bill 8 months of the year to keep it safely livable.

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

#272

Post by [deleted] »

_carbyau_ wrote: post #250
TheSpiceIsLife wrote: post #209

Earlier quoted context omitted.

This is exactly the same setup I have here in Launceston. Another great thing about having three seperate units is if one breaks, rare as it is, you're not stuck without heating / cooling.

I am leaning more to this solution for this reason. Trying to get any tradie quickly these days doesn't happen. Trying to get an aircon person in an Australian summer is worse. I despair for the rental market right now. High prices and landlords are generally crap at amenities they don't personally use.

[deleted]

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

#273

Post by rainsford »

tomohawk wrote: post #124
macinjosh wrote: post #30

Earlier quoted context omitted.

Still waiting for one of these people who rave about their heat pump system to actually rely on it full time without a backup. Most folks could barely afford to replace an existing furnace in a place that has all the fixtures installed, much less pay to install a second one based on different setup, and then pay for maintaining two systems on top of everything else. It is absurd to think that this is a plausible way…

The article is light on technical details, pointing to a heat pump vendor site for "proof" that they're great. I live in a heavily populated area with high standard of living, and yet we have had power outages lasting up to a week in the years we've lived here. Almost all in the winter, but also some due to hurricanes. We have have solar, which is great in the summer heat, but not as wonderful in the winter. We have…

At the risk of asking a dumb question, doesn't working great 99% of the time represent a pretty good solution to most problems by any standard? The tone of the post you're replying to seems to suggest having a backup heat source for rare situations is somehow an indictment of heat pumps, as if addressing your climate control needs 360 days a year without relying on fossil fuels is somehow a failure. Sure, those few days where an alternative is necessary means you might need a backup plan. But that's light years ahead of having to rely on the backup plan every day.

I'd also suggest that the necessity of a backup plan can be reduced as well. Having an unreliable power grid is probably not an immutable law of nature so much as a policy choice and modern heat pump technology performs well at considerably lower temperatures than you describe.

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

#274

Post by tomcam »

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…

> Ducts are dead

Great. You just eliminated approximately 15% of lazy screenwriter tropes for thrillers and action movies. Now they are forced to rely on replacing live surveillance camera feeds with a loop.

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

#275

Post by fifteenforty »

thehappypm wrote: post #248
teruakohatu wrote: post #114

Earlier quoted context omitted.

I hadn't considered that. My argument with split systems, at least how they are installed in NZ, is that they are usually installed in the main living area and if there is a second unit, in a corridor. So corridors are heated or cooled far hotter or colder than they need to be in order to heat/cool bedrooms.

I have two units that are heated by heat pumps in Massachusetts. One has mini splits. You definitely don’t generally put mini splits in every single room (like bathrooms or interior hallways) because each mini split requires tubing, is large, and expensive. No, I think it’s way more likely that you would have them in the bedrooms rather than the hallway

Exactly. In this example, which is pretty common here, I installed 1 in the living area and then 1 in each of the bedrooms.

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

#276

Post by dahfizz »

fifteenforty wrote: post #220
rootusrootus wrote: post #211

Earlier quoted context omitted.

That seems kind of high for insulated ducts, where does that number com from?

US energy.gov

It would be nice to actually link the source[1] (PDF).

The stat is that you lose between 25-40% efficiency for "typical" existing installations. The document goes on to explain that an insulated duct which doesn't leak doesn't have this kind of efficiency loss.

[1] https://www.google.com/url?q=https://www1.eere.energy.gov/bu...

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

#277

Post by tomcam »

mvnuweucxqokii wrote: post #163
kccqzy wrote: post #132

Earlier quoted context omitted.

Not being snarky but why don't you just open the window for that? I have a CO2 detector that I believe is a reasonable proxy for stale air. When it goes above 1000 I simply open the windows. By the time I remember to close the windows the reading is almost always below 500.

Not to be snarky, but if the weather outdoors is uncomfortable enough to be using climate control, why would I want to open the window?

Because it smells bad inside? Because fresh air feels good? Not to be snarky, but how did you miss these use cases?

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

#278

Post by mabbo »

nickpeterson wrote: post #4

Why can’t my whole home participate in this technology? It would seem an ok fit for things like freezers, refrigerators, hot water heaters, etc. When it’s freezing cold outside, it seems crazy that I warm the air of my house and then use electricity to keep the fridge cooler than the air I just heated. Someone needs to make a standard for moving heat/cool through all appliances in a house…

Your fridge and freezer are warming your home.

They move the heat from inside the fridge to outside. That heats up your home. This reduces your need to heat your home, temporarily.

Generally, every device in your home that uses electricity is creating roughly the same amount of heat as an electric heater would have using the same amount of electricity. Even fridges and freezers, so long as nothing is being vented outside.

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

#279

Post by throwawaylinux »

jimmaswell wrote: post #238
fifteenforty wrote: post #159

Earlier quoted context omitted.

It’s a ‘mini split’ in US lingo. There are thin, highly insulated refrigerant lines going between the outside unit and the inside unit. The inside unit exchanges heat with the air. https://www.daikin.com.au/our-product-range/split-system-air...

That thing's an eyesore compared to a duct to me.

They're noisy too. Not loud, it's a quiet hum, but it's annoying if that annoys you, some people are sensitive to noise. The system I have doesn't seem to have a variable-output control, so it uses an on/off hysteresis that drives me up the wall. I could deal with a constant hum, but the stop start every minute or two is annoying. A previous house I lived in the ducts were absolutely silent unless it was on high you could hear some airflow noise. They can be placed anywhere wall floor ceiling (depending on construction of course), and have a wide range of styles.

Ducts are a superior look and experience IMO, just slightly less efficient. Nothing wrong with preferring them.

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

#280

Post by monkeydreams »

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…

> In a house I own in Melbourne, Australia

Same, and we have just implemented 2 x 7.1kw units along with about 7kwh solar panels. Our heating costs have plummeted and we can survive on days like today (17th Jan) with minimal impact to our comfort.

We are looking at changing water heating next as this is now the biggest part of our utility usage.

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