61–68 of 68 posts
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Might as well just get solar PV then, that's around 150W per m2.
150W electricity, so you need to run a refrigerator cycle to pump that heat out of your house, which comes at a massive efficiency penalty.
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One question that I always wonder when hot days strike: Given that I only have one portable fan, what is the best setup at night if it is colder outside than inside: 1. Open the windows and put fan so that it blows air out of one window 2. Open the windows and have fan mix the air inside the room 3. Open the windows and put fan on balcony to blow air from outside in.
Matthias tries a few options and evaluates them– https://www.youtube.com/watch?v=1L2ef1CP-yw > Experiments and anemometer measurements to figure out where to best place a fan to optimally air out the house to cool it down at night.
- Blowing out is better than blowing in.
- Fan should be some distance to window otherwise it is ineffective.
To compare to an air conditioner. This device has about 40W of cooling per m2. Apparently in Australia you should size between 80 and 120 W/m2 of air conditioning (I think this is cooling watts rather than power usage watts) - https://www.google.com/amp/s/www.crownpower.com.au/blog/choo... So that means every square meter of living space needs 2 square meters of radiative cooling (assuming no other passive cooling in…
Might as well just get solar PV then, that's around 150W per m2.
I've been actively working on this technology, goal is making it cheaper and simplify installation. Stanford's a highly reflective surface ~95% combined with stacks layers of silica oxide on a wafer under vacume. The trick too achieving bellow ambient temperature is too reflect nearly all solar energy while emitting strongly in the "atmospheric window". Most silica compounds are well suited as emitters, however the h…
I'm really ignorant about this whole field. Your work on passive radiative cooling doesn't sound like biotech or related to biotech but your link https://www.scihouse.space is a biotech lab. I was just wondering the kind of education/knowledge someone who is working on the cooling technology would have, and was surprised to see a biotech background. So am wondering on the journey to get from biotech to whatever is ne…
This is as insane as the blackbird land yacht which is a vehicle to go directly downwind faster than the wind!
The surface being pushed by the wind is moving slower than the wind.
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wouldn't large scale usage of a device like this essentially increase the planetary albedo and help fight climate change? especially if you just skip the "environmental heat transfer" part
There's some numbers here for what it would take. https://www.cell.com/joule/pdf/S2542-4351(19)30354-X.pdf Basically we need 1W/m^2 of cooling for the earth, so if you could get a radiative cooling device with 100W/m^2 you'd need to cover about 1% of Earth's area
so the math works out even better than it seems...?
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150W electricity, so you need to run a refrigerator cycle to pump that heat out of your house, which comes at a massive efficiency penalty.
Refrigerators actually have greater than 100% efficiency, often like 300% or so. Because you're just moving the heat, not creating it. Sounds like magic but it's not.
Earlier quoted context omitted.
wouldn't large scale usage of a device like this essentially increase the planetary albedo and help fight climate change? especially if you just skip the "environmental heat transfer" part
There's some numbers here for what it would take. https://www.cell.com/joule/pdf/S2542-4351(19)30354-X.pdf Basically we need 1W/m^2 of cooling for the earth, so if you could get a radiative cooling device with 100W/m^2 you'd need to cover about 1% of Earth's area