It looked like the liner might provide insulation, so more of the air passing through the system would be cooled, rather than the ice also being melted from heat transfer through the bucket walls.

It's not clear to me how much of an effect this would have.

Why mommy can't sew!

Here's a pyro-aside this reminded me of:
U will Need:

paperclip
flint
butane lighter

bend paper-clip in such a manner as to hold flint in-place
with lighter, heat flint while holding the end of the paperclip far enough away from finger to avoid heat transfer-(flint will glow and swell twice it's size, at this point...)

Throw glowing flint & paperclip combination at hard surface, concrete, brick wall, etc.

Super explody white-sparkler-action, and really cool sound

There should be a name for this...

>> ^raverman:

...Makes me curious to experiment... If you put steak on one and leave the other in the packet both at room temp... How much faster is the defrost time? 100%? more? is there a known ratio for these things?>> ^Sagemind:
Also, I have a defrost board in my kitchen.
It's the same as a cutting board except it's made of aluminum and it has feet to maximize the heat transference.
It increases the defrost time of things like frozen meats and also affects the cooling times of things like a hot bowl of soup or something that comes out of the oven.
When you place something frozen on it, it practically freezes itself. The feet exposes the underside to the open air so it can expel the cold quicker. If it was flat on the counter, the whole thing would ice over.



It is REALLY fast, we used to have a store bought product like this, just a glorified piece of aluminum. Your talking at least a third of the time if you can get good contact, rounder objects like turkeys are a bit harder. But for steaks and hamburger, it was less than 10-20 mins straight out of the freezer, and lots easier than having to cycle out water for half an hour or so in the sink. Miracle Thaw is what I believe it was called, but you could achive similar results with just a normal ol pan...though, they aren't flat so it might not be as optimal. You could go grab yourself a bunch of old computer heat sinks with copper and blow the aluminum ones out of the water!

...Makes me curious to experiment... If you put steak on one and leave the other in the packet both at room temp... How much faster is the defrost time? 100%? more? is there a known ratio for these things?>> ^Sagemind:

Also, I have a defrost board in my kitchen.
It's the same as a cutting board except it's made of aluminum and it has feet to maximize the heat transference.
It increases the defrost time of things like frozen meats and also affects the cooling times of things like a hot bowl of soup or something that comes out of the oven.
When you place something frozen on it, it practically freezes itself. The feet exposes the underside to the open air so it can expel the cold quicker. If it was flat on the counter, the whole thing would ice over.

Also, I have a defrost board in my kitchen.
It's the same as a cutting board except it's made of aluminum and it has feet to maximize the heat transference.

It increases the defrost time of things like frozen meats and also affects the cooling times of things like a hot bowl of soup or something that comes out of the oven.

When you place something frozen on it, it practically freezes itself. The feet exposes the underside to the open air so it can expel the cold quicker. If it was flat on the counter, the whole thing would ice over.

The motor noise they may be able to work on. As for the air barrier, it may be so thin that the radiant heat transfer is enough without actual contact.

Theoretically yes, but the efficiency would be terrible with current tech.

If only relying on radiative cooling then the condenser would need to be huge just to cool something the size of a house. Of course, the hotter the coils, the more heat transfer there would be.

Then the radiation would need to be transmitted through the atmosphere. That would heat some of the air along the way, reducing the efficiency of the transfer and further increasing the amount of cooling needed to offset global warming (clouds wouldn't help either).

There's also the fact that the entire process consumes a lot of power to compress the coolant. Currently much of that power comes from sources that emit greenhouse gasses, reducing the net efficiency of the cooling offset. The machinery itself also creates heat, which would need to be offset with additional cooling.

I don't think her idea was "stupid"... she just doesn't understand the difficulties and cost involved. If we had unlimited solar power and extremely efficient large-scale AC farms then it might work, but there's also the unknown side effects of localized cooling on wildlife and the hydrological cycle.

It's a neat idea, and I'd love to run the numbers on it sometime for fun, but it's currently impractical and possibly counter-productive with our current capabilities.

In reply to this comment by jwray:
Ordinary air conditioners could only increase global mean temperature due to the law of conservation of energy. But if the condenser coils are in a vacuum surrounded by glass on top and a mirror on the bottom, then they just radiate into space.

I concede that she was lacks a complete understanding of heat transfer and basic thermodynamics.

That said, people are actively working on heat sequestering. There are types of air conditioners that are essentially a heat pumps. This idea, in particular, is one that people are interested in. Because the earth is not a closed system we don't have to worry about the 2nd law.

My point would be: making giant heat sink is not the craziest solution anyone has ever proposed for global warming.

>> ^MycroftHomlz:

This is not a as stupid as you think it is.


I'm going to say it is. Even if there's some advanced technology or hypotheses about heat transfer, they weren't running through this broad's mind.

>> ^robbersdog49:

It probably would do if he held it for long enough. When you pick an ice cube up it doesn't instantly all turn to water does it, and that's with your fingers 58°F warmer than the melting point of water. The the gallium you'd be barely above the melting point, so heat transfer would be a lot slower and it wouldn't melt, particularly if it was straight out of the fridge.


No, but ice does melt enough between my fingers that that it becomes slippery and hard to hold on to.

>> ^jimnms:

It says it melts at 86°F, so why didn't it melt in his hand? I just used an IR thermometer on my fingers and get 90°F.


It probably would do if he held it for long enough. When you pick an ice cube up it doesn't instantly all turn to water does it, and that's with your fingers 58°F warmer than the melting point of water. The the gallium you'd be barely above the melting point, so heat transfer would be a lot slower and it wouldn't melt, particularly if it was straight out of the fridge.

>> ^Psychologic:

>> ^NetRunner:
And never once is there a mistake -- the tides go out, and come in like clockwork, and even more amazingly, the molecules all flawlessly follow the laws of physics, without fail.
That isn't completely true. On the atomic level plenty of "mistakes" happen that aren't noticeable on a larger scale. Heat transfers from cold molecules to hotter ones, entropy spontaneously decreases, and particles appear/disappear at random. All we normally see are what most of them are doing, and that gives the illusion that all of the particles agree.
On the larger scale, tides are not always consistent. Oceans have been known to recede significantly when they should be at high tide. That could be seen as a pretty big "miscommunication", though if you witness it while on the beach then you might want to run towards the highest elevation available. ;-)


But those are all "mistakes" caused by gaps in our understanding, not the universe ceasing to function according to its laws.

>> ^NetRunner:
And never once is there a mistake -- the tides go out, and come in like clockwork, and even more amazingly, the molecules all flawlessly follow the laws of physics, without fail.

That isn't completely true. On the atomic level plenty of "mistakes" happen that aren't noticeable on a larger scale. Heat transfers from cold molecules to hotter ones, entropy spontaneously decreases, and particles appear/disappear at random. All we normally see are what most of them are doing, and that gives the illusion that all of the particles agree.

On the larger scale, tides are not always consistent. Oceans have been known to recede significantly when they should be at high tide. That could be seen as a pretty big "miscommunication", though if you witness it while on the beach then you might want to run towards the highest elevation available. ;-)

Bodum makes stuff like this. I have one, and I must say, it can be a pain in the ass. You can't really walk away from it--you have to be there to turn off the heat at precisely the right moment or the proper heat transfer won't happen and the coffee mixture won't drain back into the carafe. It's probably user-error when it happens to me, but I enjoy standard filtered coffee now--the automatic fire and forget variety.

>> ^Crake:

sure, it's large scale geo-engineering, but it can only lead to greater knowledge of how such systems work, and maybe greater control of them. presumably the hundreds of salter sinks will have temperature monitors as well, and could be used to actually test hypotheses, instead of just waiting for events.

Yeah, great. Let's just cool the surface of the ocean enough to disrupt weather patterns and see what happens. Are you seriously suggesting that's a good idea?

Bear in mind that the heat transferred away from the surface isn't disappearing. This could actually end up being a more efficient way of getting heat into the ocean, leading to more heat energy in the oceans and all the fun and games that would go with that.