6 ms·

Yes, I like this explanation, when that phenomenon happened in our house I thought one of our neighbours was dumb because he just put a blanket over the collect

Yes, I like this explanation, when that phenomenon happened in our house I thought one of our neighbours was dumb because he just put a blanket over the collector on the roof, as he said, "to keep it warm". But now I think he was right. Now, I don't know if this exists but it would be nice if there was a kind of glass that let radiation pass only to one side and not the other way, a kind of "valve", this could solve the problem of water frozing from radiation in our solar heating.

Enginerrrd 3y ago
>Now, I don't know if this exists but it would be nice if there was a kind of glass that let radiation pass only to one side and not the other way, a kind of "valve", this could solve the problem of water frozing from radiation in our solar heating. This doesn't exist and can't even in principle because it would be a fundamental violation of thermodynamics. Basically, it would be a Maxwell's demon for radiation that would allow you to arbitrarily reduce entropy.
- KMag 3y ago
  But, it might be possible to have a material that has different characteristics at different temperatures, as long as it's symmetric. If it's nearly opaque to IR in its cold state, hopefully sunlight at dawn would warm it rapidly enough that it would automatically "shut off" on cold nights, and still "turn on" shortly after dawn even on cold days.
  - sgc 3y ago
    Light meter controlled / tracking louvers would be the quick fix.
  - Enginerrrd 3y ago
    Yes I think that'd be ok. You'd basically just be taking advantage of the thermal gradient between the radiating body and the object being heated. It'd be analogous to adding more insulation as it heats up and removing insulation as it cools down. You'd be slowing the flow of heat into your reservoir just as much as you'd be slowing down the loss of that heat later though. You might still get some benefit in preventing freezing at the expense of needed a larger area to get the same amount of heat flow in to your water system though.
- K0balt 3y ago
  I don’t think maxwells demon is impossible, it just is a device for converting información to energy. In theory, many such devices may be possible for the conversion of information to both energy and matter. This seems like it might be support the simulation hypothesis.
- kbutler 3y ago
  We call this a one-way mirror. https://en.m.wikipedia.org/wiki/One-way_mirror https://en.m.wikipedia.org/wiki/One-way_mirror They are not perfect (intensity & wavelength limitations), but they exist. See also mirages and total internal reflection.

Enginerrrd 3y ago

>Now, I don't know if this exists but it would be nice if there was a kind of glass that let radiation pass only to one side and not the other way, a kind of "valve", this could solve the problem of water frozing from radiation in our solar heating. This doesn't exist and can't even in principle because it would be a fundamental violation of thermodynamics. Basically, it would be a Maxwell's demon for radiation that would allow you to arbitrarily reduce entropy.

KMag 3y ago
But, it might be possible to have a material that has different characteristics at different temperatures, as long as it's symmetric. If it's nearly opaque to IR in its cold state, hopefully sunlight at dawn would warm it rapidly enough that it would automatically "shut off" on cold nights, and still "turn on" shortly after dawn even on cold days.
- sgc 3y ago
  Light meter controlled / tracking louvers would be the quick fix.
- Enginerrrd 3y ago
  Yes I think that'd be ok. You'd basically just be taking advantage of the thermal gradient between the radiating body and the object being heated. It'd be analogous to adding more insulation as it heats up and removing insulation as it cools down. You'd be slowing the flow of heat into your reservoir just as much as you'd be slowing down the loss of that heat later though. You might still get some benefit in preventing freezing at the expense of needed a larger area to get the same amount of heat flow in to your water system though.
K0balt 3y ago
I don’t think maxwells demon is impossible, it just is a device for converting información to energy. In theory, many such devices may be possible for the conversion of information to both energy and matter. This seems like it might be support the simulation hypothesis.
kbutler 3y ago
We call this a one-way mirror. https://en.m.wikipedia.org/wiki/One-way_mirror https://en.m.wikipedia.org/wiki/One-way_mirror They are not perfect (intensity & wavelength limitations), but they exist. See also mirages and total internal reflection.