Oxford study proves heat pumps triumph over fossil fuels in the cold

L4sBot@lemmy.worldmod to Technology@lemmy.world – 816 points –
Oxford study proves heat pumps triumph over fossil fuels in the cold
nationalobserver.com

Oxford study proves heat pumps triumph over fossil fuels in the cold::Published Monday in the scientific journal Joule, the research found that heat pumps are two to three times more efficient than their oil and gas counterparts, specifically in temperatures ranging from 10 C to -20 C.

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Theres different technology but there are some that can function to -32° F and they often have a feature that allows them to detect when theyre frozen up and defrost and then automatically switch back to heating

Mine has a defrost cycle but it doesn't work very well. But then again, it's use case is primarily AC - it only gets frigid temps in my area every couple years. EDIT: yes, downvote me for stating my own personal experience, asshats.

Honestly it sounds like your unit may need to be serviced.

This comment section is a trip. Any time anyone is like "I have reservations about my own heat pump" and people are just responding with downvotes and "no"

I mean, it’s fine to have issues with your own unit. The only issue I personally take is when people (not this individual to be clear) use those issues as a counter argument. It’s like saying “my air conditioner has a freon leak and freezes up every year, so air conditioners are terrible in general.”

I think it's an issue that people are passionate about and the "discussion" just turns into some kind of political shouting match.

Like, it's actually been settled for quite some time: MOVING heat is more efficient than generating it or absorbing it through phase transitions. This study is just one more on a long parade saying the same thing.

What features and installation considerations exist for different climates? Do some manufacturers specialize in systems that excel in different circumstances?

I'd be surprised if they didn't. I'd be really interested in hearing who the premiere manufacturers are who design systems intended for use in Northern Canada. I'd be interested in who makes best systems for use in Phoenix. I can't imagine the same system is ideal for both places.

That's an interesting conversation to have. "Mine doesn't work good" "yes it does, fuck you" is tedious.

The crazy thing is I even left it open ended with a question mark, inviting people to enlighten me. And what I got is precisely what I wanted, along with a ton of downvotes like I was an ideologue or something. I'm an ideologue about some things, heat pumps not being one of them. Regardless, now I know that there are, in fact, heat pumps that are designed to work much better in cold climates than the one I have, and that there are plenty of cold-climate folks who find the performance of the heat pump to be sub-par in extra cold weather, requiring supplementary heat.

Right but efficiency doesn't mean it's better. Electric heat has always been 100% efficient, but that has not made it the most cost effective nor the best solution over far less efficient means of generating heat either. Efficiency isn't the only factor. The debates and critisms here are valid from what I've seen.

Personally, I'm not sold on them... maybe if I lived someplace warmer but living in Wisconsin, they are not for me. I've also seen that they require a lot more maintenence and are much less resilient compared to furnaces and central air units. I've watched plenty of installation and repair videos on them. Even the HVAC guys have issues with them in these terms.

The thing that blows peoples mind is that heat pumps are MORE than 100% efficient.

WWHHAATT?? WHAT ABOUT THERMODYNAMICS??

Heat pumps don't GENERATE heat. They move it.

In the same way that a locomotive can expend a few hundred gallons of diesel to MOVE a few hundred thousand, so can a heat pump MOVE more joules of thermal energy than it expends in the moving process.

Heat pumps are more complex then a natural gas unit, absolutely. Depending on what you're paying for energy, it's entirely possible it's not cost effective right now.

But,as the tech improves and energy costs increase, the break even point will eventually meet you, even in Wisconsin. If it's not for you right now, that doesn't make you a bad person.

But keep your eyes on it and don't write it off. I don't know how old you are, but it's still likely to end up the most effective choice for you at some point in your lifetime. Certainly in your children's.

But keep your eyes on it and don’t write it off. I don’t know how old you are, but it’s still likely to end up the most effective choice for you at some point in your lifetime. Certainly in your children’s.

Oh yeah, for sure, I keep an eye on all these types of things because at the end of the day, I'm a cheap bastard, and love long-term savings. I am going to go with the option with the highest positive expected value for me, but heat pumps are not there for my climate just right now. I'd be more then willing to convert over if that ever changes.

A lot of people also don't understand that a heat pump is still heating your home, even though the air it blows might be a bit lower than your body temperature, so it feels "cool." When that happens people assume it has stopped working and switch to aux heat. This is one of the major reasons people insist that heat pumps don't work in the cold, even though they still have plenty of capacity margin to heat the dwelling.

My old system was actually set up so that it would pulse the electric aux heater every few minutes or so to help prevent this "drafty" feeling, and to extend the time between defrost cycles.

Many parts of Canada will regularly see colder than -40F, so I can sympathize easily with a view that solely relying on them might not be safe in that environment.

Tbf, most Canadians don't live in those areas. Places like Toronto/Montreal/Vancouver rarely get that cold.

Edmonton Saskatoon Regina Winnipeg

As a Canadian who doesn't live in the GTA it drives me nuts when people dismiss the rest of Canada as some kind of statistical outlier undeserving of acknowledgement.

Which would account for 5-10% of the Canadian population. Just the three metros I mentioned would account for 35% of Canadians. The record low for the coldest of those cities (Montreal) is -36F, but the average low in January is 7F.

70% of Canadians live south of the 49th parallel (the northernmost point of the Continental US) and 90% of Canadians live within 100 miles of the US border.

Why is it such a controversial thought to merely include and acknowledge the rest of Canada, rather than discounting them outright?

In case you're wondering here the divide comes from: it's this, and it's you.

All Canadians matter, every Canadian experience is valid, and no Canadian is any less of a Canadian than any other. Erasure of Canadian experience outside of the GTA is an elitist and divisive attitude and serves ONLY to create friction where there need be none.

As soon as you erase a group from the whole, it's INEVITABLE that they'll seek to find their own independent identity. Considering your proximity to Quebec this shouldn't be a foreign concept. Just feel free to extend the inclusive attitude west as well as east. It costs nothing to be inclusive of your fellow countrymen.

Because your comment suggests that heat pumps can't work in Canada. It's like an American dismissing heat pumps because Alaska is part of the US. For at least 70% (if not more like 90%) of Canadians, heat pumps work just fine. Obviously, if you are in the part of Canada that gets consistently below -40 degrees, don't get a heat pump.

Also, I'm not from Toronto or Canadian so I'm not sure all that talk about elitism applies to me. I'm from a small city in the US where I experience weather similar to most Canadians.

My comment doesn't suggest that, and the fact that you're projecting that on me is your fucking problem.

And the fact that you're not even Canadian makes it even more absurd that you're explaining to me the nuances of the Canadian experience.

It's fine. We use geothermal heat pumps with the lines buried below the frost line. (6-8 feet below the surface.) I know quite a few houses and even a few factories (30,000 square feet+) that use them in temps that drop well below -30c to -40c without any issues.

The initial setup cost is a fair bit more because of having to bury the lines, but after that they're fine.