And it raises the heat outside of buildings. Not so good for people who have to be outside, think first responders etc.
"just turn on the AC and keep burning the world down" isn't really the answer.
No it doesn't. Seriously, where does this meme even come from? It should be pretty obvious just from a solar insolation map that AC is just noise vs the sun. The energy usage is tiny vs vehicles or non-heat pump heating and only electric. What changes temperature overall is the balance of thermal retention by the atmosphere vs radiation into space, hence why net increases in GHG are so dangerous. And at the ground level similarly how heat is dumped to atmosphere. Greenery, whites, shade etc is good, asphalt, mass standard glass is bad (hence many cities being heat islands). Old, leaky units sure, we absolutely should work to reduce that. But it's astonishing how people claim AC makes the outdoors hotter so consistently.
Yes, it does. It may be small temperature increase but AC use increases outside temperatures. It is just physics.
Here is a simple diagram: https://www.lozierheatingcooling.com/filesimages/heatPump.jp...
It would actually be a much better global warming mitigation strategy to install bidirectional heat pumps (A/C in the summer, heat in the winter) that runs on electricity (which is increasingly produced using renewables) and then get rid of fossil-fuel burning furnaces.
No heat is created either, that would explicitly violate the first law of thermodynamics. An air conditioner powered by solar energy (or anything solar powered) ends up releasing the exact same amount of "excess" heat as the sunlight would have if it hadn't been absorbed by the panels.
As an example of thermal lag: My present home doesn't have aircon upstairs. I've got a room with a west-facing window up there, and I just happen to chart temperatures in that room.
The daily temperature peaks in that room during the warmer months tend to happen at night -- sometimes, as late as midnight. The daily temperature minimums tend to happen around noon.
This suggests that solar power is least-useful for that particular room when solar availability is greatest. It doesn't overlap very well at all.
(I'm still looking into installing fairly modest solar rig, though, just to help offset my own baseload when I can and maybe make extended power outages more survivable.)
Sure. But solar panels are intentionally designed to absorb a lot of energy. So if you are putting the panels over a dark surface, like asphalt, you'll probably have a net zero effect on heat. If you put them over something light colored, you are now converting more visible light that would have been reflected into space into heat. To be clear, that is still a lot better than burning fossil fuels, but it isn't completely free either.
Let's burn more dinosaur juice instead of using passive, clean device.
But they do. And do we build the AC with solar power as well? Ship the parts around the world on sail boats?
In reality equilibrium is restored quickly (and the thermal mass we're cooling/heating here is insignificant anyhow).
This doesn't mean that there's zero heat added locally (as many seem fond of suggesting): The compressors and circulation blowers and fans don't run for free, and every Joule of electricity they consume is ultimately converted to a Joule of heat in a process that wouldn't occur in the absence of aircon. That's not zero.
But in very broad strokes, it's not very significant. It's somewhat akin to running a refrigerator inside of a kitchen.
With aircon, the refrigerator is the size a whole house. That certainly sounds huge, and it is huge. But that refrigerated building is inside of a room that is the size of the Earth's atmosphere, which is very obviously vast in ways that kitchens simply are not.
It doesn't really matter. Millions of homes with aircon don't mean much when the atmosphere is millions of times bigger than they are.
Heat pump uses electricity. It does, however, transfer more energy than it's using.
Magic of science! That page should be simple enough for the start: https://qualityhomeaircare.com/heat-pump-efficiency/
> Heat pumps convert energy to heat more efficiently than combustion-based systems, potentially delivering 300-400% efficiency compared to the 80-98% efficiency of the best furnaces and boilers.
> This fundamental advantage stems from the fact that heat pumps move heat rather than generate it through combustion or resistance.
Sadly can't edit the original comment anymore.
Humans have a really hard time understanding compounding risk. But there are billions of us. How many billions of drops can you handwave away?
Air Conditioners do not produce a net heating effect unless you power them by burning fossil fuels.
Our current cities and infrastructure are designed to be black heat sinks to soak up heat and hold onto it and ground level. But there is research into what would happen if we flipped that design around.
The sun = 175 quadrillion watts of heat.
So I would say, the heat from running ACs is not significant. It's also additive with all the other existing forms of energy use we have. Unlike greenhouse gases, which are multiplicative.
"If we all do this little thing" thinking is utter nonsense. If all of human consumption or contribution to warming or what-have-you is 1000, applying a change that lowers that to 999 is not doing anything more than that.
This here is not even a 0.1% thing. You could probably get a better result by telling people to read ebooks rather than hardback. It's just absurd.
The increase in the heat outside the houses, caused by the air conditioners running MOSTLY ON RENEWABLES[1] is a drop in the ocean. Especially if we speed up installing heat pumps powered by renewables and acting as AC in the summer.
There's plenty of good arguments and then there was yours. No, ACs running worldwide are not a net contributor to the climate emergency.
If you at least said that solar reflective paints and foils should be much more popular, along with reforestation of cities, which would then bring the cooling needs down but no, you had to do the strawman.
[1] https://ember-energy.org/latest-updates/for-the-first-time-w...
> provides diagram with zero evidence that AC meaningfully influences temperature
Clap, clap.
> A significant degradation of external thermal comfort can also be seen in the simulations, as heat released by AC systems warms the outside air (see figure 3). The temperature increases due to AC depend on the time of day and on the characteristics of the heat wave, mainly its intensity. On average, the duration spent under high heat stress conditions in the streets is increased by about 20 min per day because of AC.
https://iopscience.iop.org/article/10.1088/1748-9326/ab6a24#...
Is that increase small compared to other things, like surfaces that absorb more solar radiation? Maybe. It depends on a lot of factors, but the amount it increases the heat of the outside is certainly non-zero.
And if you stand near an AC unit, you can definitely feel heat coming from it.
The exhaust of a single car/plane/ship are also immeasurable, yet here we are...
This is an outdated attitude. PV solar panel output correlates really well with air conditioning demand, no need for storage. Overcool your thick-walled masonry buildings during the day as a form of energy storage.
They don't create heat. It was there in the first place, just a different location.
Of course air conditioning is reasonably well suited to be a solar load during peak hours, but in most parts of the world if everyone just installed AC units like are common in many parts of the US it would mean a huge amount of extra fossil fuels burnt.
Maybe Europe should sell guns to the states - ideally sold in €
When you start handling that range you've to take into account that these people are going to die because of something, save a guy from heat here and that's an extra death because of cancer 4 years later.
Now I'm not saying it's a thing to be ignored, but be wary of playing quick and dirty with statistics.
I still like to draw a parallel, because they’re both deaths that we have the means to prevent, but the culture perpetuates the problem. That culture needs to change (doable in Europe with regard to AC because heatwaves will snap people out of denial, much harder or impossible to solve the gun culture problem in the US).
It is, because we're not going to be here forever, so might as well make the best of it. Trying to stop entropy by making everyone's lives worse is ultimately futile, but a certain group of activists have certainly been trying...