In Spain pretty much all AC units can also heat the air and are still simply called AC. Then we have ‘aerothermics’ that also heat water (https://www.iberdrola.com/sustainability/what-is-air-source-heat-pumps). When I see ‘heat pump’ I think ‘aerothermics’ but it’s just AC, right?
In Australian it’s called a “reverse cycle” (one that heats and cools). our uses a heat pump as well. Heat pump hot water systems are also a thing, the name “aerothermics” for them is awesome.
OK, let me geek out for a bit:
A/C is air conditioning. One way. They actually extract heat, not pump cold in.
All mentioned systems are heat pumps.
Systems that can pump in two directions are
inverterreversible systems. Many, if not most modern AC systems areinverterreversible heat pumps. “Aerothermal” in English is called “Air source heat pump”.A heat pump is called an air source heat pump when the quantity of heat (or cold) moves exceeds the energy expended, so if you get 2 or more units of heat (or cold) per unit of energy, it’s considered “Aerothermal”, because it’s extracting that heat, in either direction, more efficiently than just burning or consuming the energy source, like gas, or electricity.
Many air to air split systems today are “aerothermal”, and are not more expensive than traditional split A/C units. Look for SCOP values higher than 4. Some of the better ones, from top manufacturers like Mitsubishi, Daikin, LG, etc. have better than 5 SCOP. These are often considered renewable equivalent, and in many countries qualify for incentives and rebates.
Obligatory Technology Connections video: https://www.youtube.com/watch?v=MFEHFsO-XSI
The phrase air conditioning doesn’t mean, one way. More common understood meaning is just cooling. However by definition conditioning to air from its existing condition to a more suitable condition is conditioning. No heating or cooling specified.
Japan/Korea aircon means something that can do both. UK, US, other commonwealth. AC means just cooling.
Thanks, that clarified a lot of things for me. I checked the stats on my Panasonic heat pump and for the last 12 months its average COP was ~4.5. So pretty good.
That’s correct. A “heat pump” is just an AC that goes both ways. They’re the most common kind of AC here in Japan too, and are just referred to as “aircons”.
Not really. All are heat pumps. if they go both ways they are
inverterreversible heat pumps.This is not correct. An inverter heat pump can adjust its output, unlike an on-off heat pump. The latter always runs at full power and regulates its output by constantly turning on and off.
You are correct. Edited.
Tu andas por la península? Aquí en las islas el aire acondicionado es menos común
Andalucía, el aire esta obligatorio :)
Huh. That’s all that was needed to get people to fight global warning? Perhaps we oughta 10x the prices.
Don’t offload that shit on the people when the problem is industrial scale
Many are fighting for their survival as is
The issue is, people will switch to solar panels and heat pumps (good), but corporations probably won’t, and prices will go down so they’ll get to continue polluting even if we clean up our own act a little.
Huh. Never heard of a “solar pump” before.
It will be deliciously ironic if Trump’s legacy is saviour of the planet for being the final straw that forcibly weens everyone off oil despite doing everything he could for the opposite.
I’ve heard people explain Trump as an extinction burst, a death rattle of a dying system. Personally I think this could go either way.
Not the hero we need but the hero we deserve.
Well said.
I’d like to think of it as a selfown. But I have to admit that necessity usually is the strongest motivator for change. I’ve had a “green energy” contract for many years. Every year I try to find, proactively, new affordable an doable solutions for my energy usage & footprint. Right now considering a homebattery for example.
I mean, Nixon founded the EPA
Interesting that you should bring Nixon up. I swear that Modern Republicans are going down a checklist trying to undo every accomplishment of Nixon and Nixon-Era Republicans.
It’s funny. The conservatives and the far right that a lot of people in Germany voted for demonized these things and now many of those voters want it to because it works. Kinda awkward, when your ideology is in the way of a better life for everyone, isn’t it?
They fell for fossil fuel propaganda. Germany is currently very close to some tipping points, which will really hurt the fossil fuel industry. Oil consumption has not gone up much after Covid and is starting to slowly fall again. A huge part of that is that the car fleet is slowly moving electric. Even relatively small changes in EV buying habits, can relatively quickly lower oil demand. It it is structural it becomes a massive issue. That becomes even worse, as Germany has a huge car industry and that turning to EVs would take away a big ally of big oil.
For gas the situation is even crazier. German gas imports halved due to the war in Ukraine. Most of that was just transiting through, but there is also a massive reduction in consumption. Heat pumps are slowly replacing gas heating in the country and a law pushed through by the Greens would basically kill the heating business long term. That is 55% of German gas consumption.
Germany also had a ton of oil based central heating. Most of those systems are going to transition to wood pellet heating. Maybe a little also to heat pumps. But common wisdom currently still is that heat pumps require suitably built houses to make sense. I wonder how much if that is just fossile fuel propaganda and how much is technically true.
Not the first time this happens either. I remember as far back as people claiming that barcodes were the mark of the beast.
Solar panels are so worth it - First month of spring, snow just melted and still the solar panels on my small house produced 1150kwh ⚡️⚡️⚡️
I wish I could do that. It’s not so simple where I come from.
Solar panels have absolutely awesome productivity from about april to may till about sept or oct, sure. But in the winter they produce nearly nothing.
Either you overproduce in the summer have nothing to do with the excess, or sell it to the grid. If you sell it to the grid, you need to be on a market rate plan rather than a fixed price plan. The market rate plan means that in the winter when your panels don’t produce shit, your electricity price per kwh shoots up as well, since nobody else’s panels are producing anything either AND demand is up by a lot.
Now if I had like a summer house that I just vacate in the winter and run zero electrical appliances, then it would be a net positive to have panels and a market rate plan there. But for year-round living, you really want the fixed-price plan, so no selling electricity back to the grid.
Basically the way the energy market works here, it’s honestly punishing people for having solar at home. Large solar parks are fine, but solar at home? Better be prepared to start paying more for electricity when you need it more.
Edit: It has apparently changed in recent times and it’s now possible to retain a fixed price for buying electricity even if you’re also a seller. It wasn’t an option before. That changes things significantly. Still a bunch of annoying extra costs to get started (the power grid is run by a for-profit company so everything you ask of them costs money and they’re REALLY annoying about any change in your connection parameters such as installing a different meter so it would also count electricity sold to the grid)
Batteries, mon.
The issue is the winter. Mean amount of sunlight per day in the winter is about 30 minutes for a few months. 6 hours between sunrise and sunset, and overcast most days. Electricity does NOT get cheap in the winter, even the nighttime prices are eye-watering if it’s cold.
I did however find out it’s possible to keep the fixed price for buying now even if you also sell to the grid. A while ago that was not an option. This changes things a lot.
Have you considered a heat pump? Because they’re basically heat exchangers, they move the heat rather than creating it and thus use a shitload less energy
I’m not trying to be a sanctimonious twat here btw, I know there’s been a lot of disinformation about more efficient technologies, and a lot of people have simply just never heard of, or are unaware of just how established and proven alternate technologies are.
You can invest in batteries. Then you can store the energy produced and use it later, like at night time. You can also buy electricity when it is cheap for the battery and then use it when it is expensive.
I’d need to store 3-4 months of energy for the winter lol, 10 MWh should more than suffice for personal use.
Mean sunlight per day is about 30 minutes in the winter months since there’s about 6 hours of daytime and most days are overcast.
10 MWh is a lot for just 3-4 months. Do you have a Jacuzzi and heated pool? 😅
For the months you can’t produce enough electricity, you buy the electricity during the cheap hours and then use it during peak hours, when it is most expensive.
Heat pump and a cold climate. Now I wish I had a jacuzzi! Curse you! A heated pool or jacuzzi or something outdoors would be peak luxury for me tbh.
There are no cheap hours in the winter, there are kinda expensive hours and super expensive hours. Worst I’ve seen is 5 euros per kilowatt hour, which is the price cap. Luckily that only happens a couple of times a winter, if that.
I did just find out that some providers allow you to keep a fixed buy price even when you also sell back to the grid (which can’t be fixed price). So that could change the math quite a bit.
There’s also the option of simply donating the excess to the grid (not having a sell contract) lol
Where do you live? I also have a heat pump for hot water and floor heating. Compared to winter, it barely runs in the summer months, but sounds like you live in a colder place than Danmark?
There’s still money to be made (saved), by buying during the cheapest hours and using it during the expensive hours.
I can save about 1-2 EUR every day by buying during cheap hours and using it during expensive hours. Days I can just use the sun, I of course save even more, because I barely have to buy any electricity, except for a few hours at night.
Compared to winter, it barely runs in the summer months, but sounds like you live in a colder place than Danmark?
Ha, I know you’re an authentic Dane by how you spelled Denmark! I live in Estonia, slightly colder, but not the coldest. I haven’t yet gotten around to installing an air-to-water or ground source pump yet, so mine only heats the home, not the water (meaning I spend a whole lot of electricity on my regular boiler year round). It’s been running 24/7 since October currently, more or less. I could just go heat my furnace right now and turn off the pump, but that’s extra work + firewood costs money too. Long term goal is to replace the furnace completely, with a ground-source heat pump with vertical collectors since my garden isn’t big enough for horizontal.
There’s still money to be made (saved), by buying during the cheapest hours and using it during the expensive hours.
Definitely same here, but I have a fixed price package and in the winter, the lows barely ever get to the level I pay year-round. This makes more sense for me since I use much less electricity (barely any) in the summer compared to the winter.
However, as I said previously, I discovered that it’s now possible to keep the fixed price for my electricity purchasing. If I got a couple of panels, they’d more than cover my electricity use in the summer and I wouldn’t have to worry about the price - and in the winter, I’d still be paying less than everyone on a variable rate plan like I do now. If I could also install some small turbines on the roof, that could actually halve my power bills in the winter too.
Only trouble is, I bought cheap roofing materials knowing I won’t have any use for solar panels anytime soon, and it won’t support the weight lol. Oh well. I saved like a thousand or two thousand euros compared to more expensive roofing materials at least.
Saving 1-2 EUR per day with a 6000+ EUR battery pack sounds…not worth it.
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Europe is already feeling the consequences, with the benchmark Dutch TTF natural gas price surging around 70 per cent – putting March 2026 on course to be the highest monthly increase for European gas prices since September 2021.
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People are " tired of being held hostage by fossil fuels"
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Context: Per 2024 nearly 50% of EU electricity came from renewables according to Eurostat
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Imo, the share of renewables in our energy production will certainly keep increasing, and our oil energy dependency will keep dropping.
There also are a lot of laws coming into effect, which have been passed to deal with the Russians turning of their gas and oil supply to the EU.
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Who knew the fat old orange pedophile would create massive demand destruction for his big beautiful fossil fuels.
Since the EU has 240V service those window heat pumps would be perfect.
Just don’t tell them it also does air conditioning or they’ll end up soft and pink like us Americans.
Amateur hassle with a box at your window, really ugly, usually we place a multy split arco through the house in europe
Window heat pumps?
Wouldn’t that mean you’d need one for each room while hearing it in every room while also seeing it in each room where it blocks a window while having to install those dreaded American push-up-windows in lieu of our beloved tilt-n-swivel ones?
Nah, thanks, I’m good. I’ll get one central heat pump for the house and that’s it.
Good luck running duct work or even mini-split tubing through that ancient European masonry.
There are machines for just that.

I don’t see any problem, most professionals have suitable material to drill through wood, brick or concrete, to thicknesses of 1 m.
Probably difficult to understand for people who live in houses with cardboard walls.
Have 37 years of experience in this matter
Professionals aside, any self respecting DIY store will readily sell you masonry drills in lengths suitable for most walls. And in the rental section, you’ll be able to get a core drill plus the appropriate machine (exactly the kind of equipment professionals will use for big holes in thick walls) for making any hole too thick and/or too deep for a regular drill. Since core drills can be extended, your drilling depth (for practical purposes) pretty much is only limited by the number of extension rods you have available.
I fully agree with your explanation.
A thick wall penetration of more than 1 m requires some experience and respect for safety.
That … is no problem? How do you think we Europeans live?
One company I worked at rented pre-war building and installed big AC in couple of rooms. Big units at the balcony and ducts through 1m walls. 0 issues.
I just won’t. Why on earth would I run those butt-ugly air vents through my house when I can just use the existing underfloor heating to cool down the building via a heat pump in the summer?
Because the under-floor heating running in a cooling loop will create condensation on the floor? Or worse, under it?
That’s why you do it gently ;).
But seriously, it’s an established solution. You don’t need to cool the floor down so much because the area is so big, so you don’t run into condensation issues.
Adding that to a house sounds even more invasive than duct work
You’d only be adding a floor heating system to a room you’d be at very least tearing the floor out of for renovation anyway. So in terms of invasiveness, it’ll only slightly prolong the work that’s being done, and create some dust from cutting slots for the piping.
In rooms that aren’t due for such a renovation, you can use existing radiators with a heat pump, too. Of course it won’t be as efficient as with floor or wall heating, but it will work. As with everything, perfect is the enemy of good enough.
But they said they’d use the existing underfloor system, so there’s no need for invasive work.











