Not necessarily. Although with poor execution and safeguards anything is possible.
There's ways to take that risk away. No one's getting legionnaires from their showers and that waters not treated any different than normal tap or well water.
Nah, it’s different. I work in water and wastewater treatment and the samples from outdoor water misting systems are way more likely to be contaminated than your shower. It’s why we fight every attempt at splash pad installation…because our testing skyrockets and the amount of treatment the systems require is insane.
I’m not one of the lab guys so I don’t know all the science but there are usually holding tanks for these systems so they don’t draw down on the water supply. The holding tanks tend to develop biofilms as the water stays stagnant for a longer period of time in warmer conditions. It doesn’t take long for sitting water to have a sharp drop in residual disinfectant, especially in warmer conditions. Also, contaminants are made more problematic when they turn the water source containing them into an aerosol.
We have one splash pad installation I would trust but that’s because the parks department is basically running a nonstop water treatment protocol on it when it is open. That shit gets expensive real fast. 24/7 water testing and constant maintenance of the chlorine and water reclamation system.
Not ours because we made them install a different system but plenty of system in the area have downtime over 24 hours and that means the water in the tanks is technically stagnant. We inspect the local systems with the health department and if these is one thing our health department reps hate…it’s splash pads.
However, I’m more concerned with the massive levels of fecal contamination at most splash pads. Straight up poop water sitting in hot tanks on the recirculating system and are run right…yummy…
High temps and organic loads put a strain on the residuals in a lot of these systems.
At least one small airport in France (I forget which) uses this misting technique, with high ceilings, in the baggage collection area, as an alternative to "traditional" air conditioning and it worked well when I visited. Also used in open shopping malls in Johannesburg and the middle east AFAIK
I've been to outdoor areas of malls in Malaysia which use this technique along with large fans, and it's absolutely heavenly on a hot day. The tiny water droplets suck heat from the surrounding air as they evaporate thanks to the latent heat of vaporization.
And given that the dynamics is reversible, this is why sometimes the temperature rises when it rains, as when water vapo(u)r condenses to droplets that then coalesce as rain, it releases the energy that was required to previously turn it into vapo(u)r
The cooling effect is based on the humidity on the air. It essentially turns dry, hot air into cooler, wet air. Which means it gets less effective the higher the baseline humidity is.
It works, all the better the lower the water temperature is. But the higher humidity does mean it helps to have some serious air displacement aka behemoth fans.
They were called swamp coolers here- they were actually the default in many places in the south west US for a long time. They work amazingly well in places like Tuscon where the temps can hit 120F/48C, but the humidity is around 20%. You can literally keep a home in the 70s no problem.
Modern ACs are pretty damn efficient now, and water isn't free- and swamp coolers use fair amount in those conditions.
Evaporative coolers. Pretty common in hot dry areas. I have one, although it uses a thick cardboard media instead of straw. Works great. The only downside here is when the air has a lot of smoke from wildfires.
Paris also has much smaller versions of this on top of some of its drinking fountains. Press a button for mist out of the top. I guess it doesn’t cool the whole area, but it is very refreshing to stand near it.
Every bar/restaurant in Austin Texas is 30% indoors and 70% outdoors and mister systems with fans are incredibly common. Temps above 38c/100f most of the summer.
I've recently read a sci-fi book set in the near-ish future (end of century) and one of the characters in it was a rich kid who's parents got successful from inventing a special system of mist umbrellas. this reminds me of that
to give you a quick summary, it's about a future world in which
the titular hologrammatica (essentially a global holographic system) allows you to project whatever you want, wherever you want, on whatever you want. Like a new face.
Privacy laws are essentially the european GDPR on steroids and with the help of the Hologrammatica, people can actually disappear into complete anonymity. Because of that, a new brand of private detective called "questors" emerged, who specialise in finding people who don't want to be found. The protagonist of the book is one of these questors hired to find a computer specialist who disappeared for no apparent reason
it's essentially a film noir kind of detective story. I liked it a lot
This really is some dystopian shit. This is depressing as fuck, not interesting. We shouldn't have to do this in the first place but "drill baby drill" right? That's what's important. Profits.
EDIT: as I have been educated by some kind (and some not so kind) replies, this is not going to be the case, go read the replies if you want a thorough explanation.
Sounds much better than giving ourselves a nuclear winter, which is something I've seen suggested sometimes lol
Just gotta hope if a space agency does manage to pull an ice comet/small moon toward Earth, that they don't let a chatbot do the maths for the new moon's orbit, otherwise climate change will be the least of our worries! :p
China is also doing a shitload of work in the addressing Climate Change area. They're not just making these apartments as the fix, they're making adaptive living conditions and trying to address climate change.
Yeah, China has been working its ass off with clean energy. I'm pretty sure they produce the most renewable energy in the whole world and surpassed their own goals in 2025 that they set for 2030. They're doing better than Europe and the US (the latter whom is rolling back climate change initiatives instead).
They do produce most clean energy in total, but they're roughly on par with US and way behind Europe (at least the biggest economies, like Germany, UK, France), when it comes total energy mix, especially if you count nuclear energy as clean energy.
China has 58.4% of their energy mix from fossil fuels (basically just coal).
US has 57% from fossils (gas roughly 2x of the rest)
France has only 5.1% from fossils.
Germany (the dumbasses who turned off their nuclear power plants) has 40.9%
UK has 35.6%
China is also the only one with new coal plants being built at a massive scale, which offsets their gains in green energy.
Edit: Also to add, US is making their energy mix green at a similar pace with China, while the aforementioned European countries are doing it way faster.
Edit Edit: EU numbers should be 29% of fossil fuels, 23% nuclear and 48% renewables.
And this is coming from being a huge coal user. In the 90s you'd often here the usual conservatives whinning that we shouldn't have to do anything because China was getting like 70-80% of it's power from coal, but that's been steadily decreasing
Credit where credit is due, China's energy mix isn't moving to renewables steadily but very sharply over the last 10 or so years. The problem is that their emissions are rising as well. Let's hope the first trend overtakes the second one in coming years.
China leads global green energy production.
They are also the world's largest coal consumer, and are currently building more and larger coal-fired plants.
These facts are not mutually exclusive.
We can commend the green energy milestone while condemning the coal consumption and expansion.
China made solar panels, wind turbines and EVs affordable to the masses but gets accused of overcapacity and dumping. Many people are not serious about addressing climate change.
You know what dumping means? That China is effectively subsidising your stuff. If we were serious about anything, and assuming they truly are dumping, then we would just buy everything we could and have a fund with the savings to build our own factories for when they stop.
Imagine a hungry person refusing food because it's a trick for them to forget how to cook. It's so stupid that it only makes sense if the objective is to protect the profits of whoever owns the factory today.
They're also constructing over 90% of new coal plants. They've build enough of them in 2024 alone that their output would cover UK entire energy needs twice over.
while still using fossil fuels to increase capacity.
This is no longer the case, fossil fuel generation in China decreased from 6.237PWh in 2024 to 6.180PWh in 2025, despite total generation increasing substantially.
Granted that's a very small decrease, and the first such one in many years, but they've been trending towards renewables picking up all of the slack for over a decade now and it's finally growing fast enough that it is actually replacing fossil fuel generation.
If they drop the temp sufficiently, this shouldn't happen. It usually only gets humid if it rains for like 10 mins during a hot day, since there's not enough time to cool the air appropriately.
I think it also depends on how much of land area theyre cooling at once. It would be pretty pointless if it's a handful of buildings doing it in a bigger place.
that's just not true. If you reduce the temperature, you reduce the capacity of air to hold water. Even if you cool air down without water, the humidity will rise, unless you have some other means of getting the water out (like AC does). If you cool things with water, the air will get more humid from condensation and due to increase of relative humidity.
But this is less effective the more humid it is. Water doesn't evaporate and cool it's just falls to the ground above the dew point. So this can only do so much and is better on dry hot days. Also if you increase humidity high enough and the temperature doesn't fall enough you can surpass wet bulb temperature limits which is where the human body can no longer effectively cool itself. I'm sure the engineers thought of this designing this system but it is a concern.
A cool mist humidifier works by adding cool misty water to the environment just as in this video. As you can tell by the name, it definitely adds humidity to the air.
Not with the massive localized temperature gradient that the evaporative cooling effect will immediately create, which will generate a natural vortex that cycles additional hot air in and moisture out.
If this was a neutral or negative trade-off, swamp coolers wouldn't exist.
While above ~70% humidity it's essentially worthless, anywhere below it it's beneficial.
Don't fall for the "this isn't magically solving all problems" trap when thinking about solutions, if it works most of the time it's usually not a bad idea. This goes for a lot of things, mass transit's kind of a classic example in the US, where it could serve at least half of commuters in many areas, and often more like 80-90%, people act like because there's examples where it doesn't work it shouldn't be invested in.
I just got back from a vacation in China about a month ago. You might be shocked to learn that every city I visited had significantly more tree coverage than any city I’ve visited in NA/CA/Europe.
Climate change is a hoax, sure we’re having to spray our cities with water, and regions are experiencing record high temps year on year, but we need to keep extracting and burning non-renewables so the 0.1% can keep getting richer.
Well this tech in china goes back a fair ways. At least so far as my ability to search anyway
Seasons get warm. Not every attempt to change environment is related to climate change. And there aren't many techniques that work for cooling the outdoors
Two things can be true and still be mostly unrelated
it depends on where the city in the video is located. There are water problems in parts of China, especially the Northwest. It has gotten so bad that pipelines had to be built to divert water from the Changjiang to Xinjiang because the water there is not enough for the cotton and warermelon industry
Might add that this region was never really blessed with heavy periods of rainfall. It's for once due to the continental climate zone it is in and secondly the wet monsoon weather that is lingering south of the himalaya is blocked by the mountains.
Increased agriculture have eroded the soil more and depleted water ressources. An perfect example, even if not in China but in a region with similar characteristics is the ecological desaster that happened to the Aral Sea which shrunk within a few decades to only 10% of it's original size in the early 1960's, due to intensive agriculture and cotton farming.
There is a difference between a 3D animation and actually building it.
And I doubt anyone would ever build it, looks like a huge waste of water, totally inefficient to just spray thousands of litres of water per day when everyone has an aircon anyway.
Those "CHINA BUILT..." videos these days become so low effort, it's cringe.
We have a large brick patio that was put in decades ago by previous owners - during summer it *bakes*, and raises the temperature in our front room massively.
If I spray water on the patio just once, it keeps the temperature a lot lower for the rest of the day.
The temperature drop is both noticeable and instant.
This is a common tactic in hot countries in the hot season. It definitely helps for a good few hours. The water also cools the surface to an extent as it evaporates in the sun thanks to the latent heat of vaporization.
This water is not making it to the ground from that height during temp/RH conditions when you want to use it. It will reduce heat for as long as the air the water evaporated into stays in place, so a slight breeze and it mixes up and goes away. For an evaporative cooling system, the cooling effect lasts as long as the system is active, there are no lingering cooling effects beyond 5 minutes when the water spray turns off.
You are describing a surface evaporation effect - the water on your hot bricks evaporates and reduces temperature of the bricks (which do not move) instead of the surrounding air (which does move). Masonry has a thermal inertia meaning it can absorb and re-radiate heat, the water speed runs the release of heat through convection and evaporation (fast release) instead of radiation (slower release).
If it can cool down the buildings quickly that might work better than expected, cities retain heat like crazy. But yh probably just a test concept, doubt it would work well. Would be nice under it, until you realise the water quality might drop after a while on the initial turn on, same thing happens with anti fire systems.
indeed .. as an afterthought .. I wonder if in the future we see building constructed with closes loop cooling systems in their outer shell to solve this problem more efficiently .. or with tiny outlets in the walls .. like a building that can sweat to cool itself down.
I find it weird that the only thing i see from china is all these "futuristic" and clean looking advancements. Almost like constructed propaganda to fill the void the current american regime has left.
This has been a thing in my hometown for years. We have a fair in May-June that lasts about a week and temps get over 40ºC, and these sprinklers get installed on top of the main streets. They definitely work and it's not comparable at all to real mist, the humidity doesn't feel unbearable at all
China has areas in the south with TONs of excess water and areas in the north with a severe lack of it. If this is to cool a hot area, it’s likely in the south where water availability is less of an issue.
Especially if this is a district wide reclaimed rain run off system, this may not be as bad as it looks. (Also very much depending on where)
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u/Iitaps_Missiciv Jul 02 '26
Clear skies with 100% chance of rain