That’s why we need passive daytime radiative cooling. In theory, it could completely eliminate the urban heat island, but it still seems to be mostly at the pilot project stage so far. I did read somewhere that you can DIY with some packaging tape (which somehow has the right properties?) over a reflective backing. Maybe I’ll experiment a bit this summer.
There is a lot of passive system to prevent heat to come in, in the first place.
- Brise soleil (sun-breaker) - these systems prevent direct sun to go through the window in summer, but let it in to heat up the habitation in winter.
- Trees ! - Trees have a cooling effect in summer and a keep the warmth in winter. They also improve air quality, physical and mental health. Increasing the areas covered by trees in city could bring down there temperature by several degrees.
- proper thermal insulation.
Yeah, I’m a big believer in shade trees! The one in our front yard has grown tall enough to provide blessed relief from a blazing afternoon sun. The only problem is the dude next door, who’s heavy into solar, is worried it’ll block his panels. And I’m a believer in solar too, so I don’t know what to say. Maybe we can come to some sort of compromise…
proper thermal insulation
what an understatement. it’s very unsexy but also incredibly effective. if your house is over 20 years old, you don’t need fancy-ass blinds, you need to get your house insulated ASAP. everything else must wait.
insulation is the number one most effective thing anyone can do to improve the energy use of their living space. only when your house is properly insulated can you think of shade management, greenery, passive ventilation, heat pumps, etc. in an insulated house, those either won’t work at all or will be wildly inefficient.
You totally can.
I’m planning on making some panels to help cool my garden in an attempt to help plants survive extreme heat and sun by shooting some of that heat into space! The combination of partial shading with cooling mass vs heating mass should help a bit. People think it doesn’t work, but I’d imagine growing a garden on a asphalt blacktop vs white cement would make a few degrees difference. This technology does the same thing, it just pushes the boundaries further to cool below atmospheric temperature.
https://www.youtube.com/watch?v=dNs_kNilSjk
https://www.youtube.com/watch?v=N3bJnKmeNJY
You’re the first person I’ve seen bring this up, not sure why it’s not more popular, just new I guess. Also, usually when I bring it up people say it’s’ bad because it will encourage more fossil fuel growth and they totally miss the point.
Here is an alternative Piped link(s):
https://www.piped.video/watch?v=dNs_kNilSjk
https://www.piped.video/watch?v=N3bJnKmeNJY
Piped is a privacy-respecting open-source alternative frontend to YouTube.
I’m open-source; check me out at GitHub.
Infinite environmental destruction glitch
FTFY
Smart enough to understand heat pumps dumb enough to think it’s has that large of an effect.
In cities it actually does have an effect, especially in crowded ones. Millions of people in a relatively small area blasting AC “exhaust” out of their windows heat up the crammed air and in turn the buildings, streets, etc. which increases the heat island effect of cities.
Granted, it’s not a huge effect, but it’s measurable. First source I could find: https://www.euronews.com/green/2023/08/30/fact-check-is-air-conditioning-making-cities-hotter
see I’ve been wondering if a heat pump system could heat an oven hot enough to bake bread. use environmental heat to manufacture Wonder Bread or something.
I don’t know the answer, but it this did work it would both make the outside of the oven super cold and be so slow to warm up that it would be pointless. Keep in mind that you have to get stuff in and out so air exchange is inevitable, every time you open the door you’d be reducing the heat substantially and it would take a long time to rise back up.
Also my gut feeling is that any practical implementation wouldn’t be as energy efficient as you’d hope.
I don’t see why it shouldn’t be able to. You might need concentric shells depending on the power of the heat pump.
Huh guess so. But still 2.4 degrees ain’t a whole lot (well except on a global scale lol). Thankfully in this situation doesnt really cause additional global warming problems.
Cities are already about 5C hotter than the surrounding countryside. Adding this increase on top, means 7.5C.
4OC in the countryside is already bad, 47,5C in the city is deadly for a lot of people.
I think you underestimate, how deadly heat can be: https://en.m.wikipedia.org/wiki/Wet-bulb_temperature
I remember a statistic claiming that at the peak of the Iraq war, the annually power consumption of US military ACs alone exceeded that of the African continent.
If only there were these things that grew out of the ground that cooled you home with their shade… What were they called again?
If only people who lived in houses understood that not everyone lives in a house.
+1 although trees can shade the ground around the building and cool the area that way too
