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submitted 3 weeks ago* (last edited 3 weeks ago) by [email protected] to c/[email protected]
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[-] [email protected] 18 points 3 weeks ago

If only there were these things that grew out of the ground that cooled you home with their shade.. What were they called again?

[-] [email protected] 8 points 3 weeks ago

Lamp posts? Radio towers?

[-] [email protected] 6 points 3 weeks ago

If only people who lived in houses understood that not everyone lives in a house.

[-] [email protected] 11 points 3 weeks ago

It is still highly beneficial in term of heat when there is a lot of shade in a city.

The tarmac gets really hot and release that heat for a long time.

[-] [email protected] 6 points 3 weeks ago

+1 although trees can shade the ground around the building and cool the area that way too

[-] [email protected] 5 points 3 weeks ago

they also convert some of the sunlight turning air into sugar instead of getting warmer

[-] [email protected] 4 points 3 weeks ago

That is an urban planning problem

[-] [email protected] 3 points 2 weeks ago
[-] [email protected] 7 points 3 weeks ago

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.

[-] [email protected] 4 points 3 weeks ago* (last edited 3 weeks ago)

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.

A illustration of a "Brise-soleil"

  • 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.

Increasing tree coverage to 30% in European cities could reduce deaths linked to urban heat island effect

A street in Brooklyn with cars park on both side and a full tree canopee

  • proper thermal insulation.
[-] [email protected] 6 points 3 weeks ago

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.

[-] [email protected] 2 points 3 weeks ago

I've added it at the end because it seemed obvious to me but yeah, insulation is the first thing to do. Especially under the roof.

[-] [email protected] 5 points 3 weeks ago

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…

[-] [email protected] 3 points 3 weeks ago* (last edited 3 weeks ago)

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.

[-] [email protected] 1 points 3 weeks ago

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.

[-] [email protected] 6 points 3 weeks ago

Infinite environmental destruction glitch

FTFY

[-] [email protected] 6 points 3 weeks ago

Smart enough to understand heat pumps dumb enough to think it's has that large of an effect.

[-] [email protected] 18 points 3 weeks ago

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

[-] [email protected] 4 points 3 weeks ago

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.

[-] [email protected] 1 points 3 weeks ago

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.

[-] [email protected] 2 points 3 weeks ago

The other part of the idea is use the heat pump to not only heat an oven to bake bread (or do some other industrial heating process) but have the other end cool some process that produces waste heat, such as a data center or something. Or air condition a warehouse.

[-] [email protected] -1 points 3 weeks ago

I don’t see why it shouldn’t be able to. You might need concentric shells depending on the power of the heat pump.

[-] [email protected] -1 points 3 weeks ago* (last edited 3 weeks ago)

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.

[-] [email protected] 1 points 3 weeks ago

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

[-] [email protected] 2 points 3 weeks ago

Wouldn’t those 2.5C already be included in cities being 5c warmer..?

[-] [email protected] 1 points 3 weeks ago

No, since most cities are not fully air conditioned.

[-] [email protected] 5 points 3 weeks ago

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.

[-] [email protected] 9 points 3 weeks ago

turns out running AC to cool tents is super inefficient. Who could have known?

[-] [email protected] 3 points 2 weeks ago* (last edited 2 weeks ago)

I've thought about the same shit and that's true lol
Covid lockdown was the best days with climate Hope everyone will understand what's causing global warming

[-] [email protected] 3 points 2 weeks ago

Global warming lockdown, let's do it 🤣

[-] [email protected] 1 points 3 weeks ago

Then heat pumps in winter will lower winter temperatures.

[-] [email protected] 1 points 3 weeks ago* (last edited 3 weeks ago)
[-] [email protected] 0 points 3 weeks ago

Unfortunately it does not work that way :(

[-] [email protected] 1 points 3 weeks ago
[-] [email protected] 1 points 3 weeks ago

I don't think that's how anything works

[-] [email protected] 3 points 3 weeks ago

It does and in two ways

  1. running a refrigerator with an open door in a closed room makes the room warmer not cooler. The fridge just moves heat around but there is inefficiency too that comes out as excess hear

  2. using energy to cool your personal space, increases global warming leading to a need for more air conditioning

[-] [email protected] 0 points 3 weeks ago

Nope. An AC just moves temperatures around. If it heats one area, it cools another.

[-] [email protected] 4 points 3 weeks ago* (last edited 3 weeks ago)

Except it is not 100% efficient. It will have losses, which will add extra heat to the surrounding area over what was removed from the target area. Thus contributing to the increase of entropy in the universe. And bringing us one step closer to the heat death.

[-] [email protected] 0 points 3 weeks ago

The real trick is to reverse-cycle your AC, and pump the heat into your home. Because of math and algorithms, this one trick will decrease entropy and take us further away from the heat death.

[-] [email protected] 2 points 3 weeks ago

That's legitimately how heat pumps work, except without decreasing entropy unfortunately

[-] [email protected] 1 points 3 weeks ago

Damn, I really thought we had it this time...

[-] [email protected] -1 points 3 weeks ago
[-] [email protected] 1 points 3 weeks ago

ACs also generate heat as a waste product (they’re not 100% efficient), but I’m not sure that actually heats up the surrounding area to a noticeable degree.

[-] [email protected] 0 points 3 weeks ago* (last edited 3 weeks ago)

Yes your right should have been more clear. If AC moves hot air from a house. This hot air goes out then imagine hundreds of AC doing that. Would that in turn heat up the area around it.

[-] [email protected] 2 points 3 weeks ago

You need some lessons in thermal dynamics my man.

[-] [email protected] 1 points 3 weeks ago

As long as the temperature inside remains constant, as much cold leaks out as is transported inside. So the only residual heating outside would be from inefficiensies in the system, not the moving process itself.

this post was submitted on 28 Apr 2024
53 points (93.4% liked)

Showerthoughts

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A "Showerthought" is a simple term used to describe the thoughts that pop into your head while you're doing everyday things like taking a shower, driving, or just daydreaming. The best ones are thoughts that many people can relate to and they find something funny or interesting in regular stuff.

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