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Fridge Cools With Fire (For Real)

Posted December 10, 2008 9:25 AM

From OhGizmo!:

Refrigeration is very important, and not just to keep your yogurt from developing sentience. It's vital for medication and food preservation and lemonade. Most of the world, though, doesn't have easy access to those little holes in the wall that most modern refrigerators demand, so some very clever people have developed a cooling system that works by heating stuff up, no electricity necessary. Yes, that's right: to get this refrigerator to work, you light it on fire. The basic principle of making things cold is that a sub-zero liquid, like ammonia, is able to act as a refrigerant by sucking up heat as it boils off into a gas. The tricky part is getting ammonia into liquid form in the first place. The refrigerator you have in your kitchen does this with electricity, by pressurizing the ammonia with a compressor. An absorption refrigerator, on the other hand, uses any source of heat: a mixture of gaseous ammonia and water is boiled, and the ammonia evaporates off. When it cools down, it turns into a pressurized liquid, ready for cooling. Chill your beer, reflame, and repeat. The designers envision an eight pound device about the size of a thermos (they've got working prototypes) that you put over a fire for half an hour, let cool for an hour, and then stick in a 3 gallon insulated container which it will cool down to 3 degrees above freezing for 24 hours even if it's 90 degrees outside. In high volumes, they'll cost about $25 each to make, in low volumes, about $40. Video explaination from the inventor, after the jump.

Read the whole article and watch the video

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#1

Re: Fridge Cools With Fire (For Real)

12/10/2008 12:08 PM

Absorption refrigerators have been around for many years, wikipedia says they first went into production in 1923. They are often used in RV's and other places where you don't have much power, and you only need a small fridge. The only thing new I see here is that he made a small one to be used on a camping trip. Not that it isn't a cool gadget but its not really new. He should do it without ammonia since high concentrations of ammonia like what is needed for this device, can kill you if it leaks.

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#2

Re: Fridge Cools With Fire (For Real)

12/10/2008 2:56 PM

so its not new, he plans to save the world of a few food poisoning diseases and to slightly raise a healthy living for everyone not as fortunate, whos to say it doesnt serve them right if they cant follow directions and end up cracking open the container and drinking the amonia. in some countries it might be the equivalent of someone taking an axe to a nuclear submarines control rods... not very bright. so personaly, kudos to the man who wants to save the world one left-over at a time. I think its an ingenius idea, I know i will buy one for when i go camping. id even buy one for my home except i have no open flame. this man deserves a medal.

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#3
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Re: Fridge Cools With Fire (For Real)

12/11/2008 7:51 AM

I agree with you, and will buy one for camping. I'll also use it at home in the event of a power outage. I have a gas grill, and charcoal grills, and can always, in a pinch, build an outdoor fire. As he notes, everyone has fire. But not everyone has electricity, nor, if they have it, all the time, or reliable.

There are always nay-sayers, to everything. The trick is to take what they say to heart, in so much as it helps to be safer, wiser, less-gullible, etc., but to ignore their ingrained negativity, and get on with what is important to you.

I think he deserves kudos, also. And his enthusiasm is infectious.

Mike

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Re: Fridge Cools With Fire (For Real)

12/11/2008 10:08 AM

I wasn't really trying to be a nay-sayer, I was just saying it wasn't new technology. I said its a cool device, its just not new. I think it could be good for camping depending on how much it weighs and how well it works. You can already buy a fridge that runs on propane that utilizes the same principle if you are looking for something in a power outage.

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#5
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Re: Fridge Cools With Fire (For Real)

12/11/2008 10:48 AM

True, thanks. And I agree that it isn't new tech. However, it IS small (at least the model was) and he said it's only 18 pounds (even in my utility trailer every pound adds up), and the propane fridges are fairly pricy (at least the ones that I've seen) in comparison to the manufactured cost of USD25 in quantity, and USD40 in small lots. Either of those, with a 100% markup from the manufacturer to delivery (Wal-Mart, anyone?) would still beat the price of any propane fridge I've seen. And with an already extant ice-chest of good size and insulation in my trailer, that cooler would be ideal. Two would be better, since we spend WAY too much money buying ice now to keep food cool on long trips.

I see a slew of ways to use this that would help us out tremendously, even in a tech rich, power stable country like most of the US. And as he points out in the vid, the usefulness to many countries makes it look like a toy for us.

Mike

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#6
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Re: Fridge Cools With Fire (For Real)

12/11/2008 11:08 AM

Just to help the lbs not add up to quickly in your utility trailer, the device weighs 8lbs.

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#8
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Re: Fridge Cools With Fire (For Real)

12/11/2008 11:47 AM

Ha, better yet. I'll have to clean my ears out, though. I thought he said 18 lbs. 8 is better. I can carry that in my backpack all day long, and have a cold soda at the end of the day (insulated backpacks are cool. Pun intended.)

Mike

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Re: Fridge Cools With Fire (For Real)

12/11/2008 11:15 AM

I watched his video, which I hadn't done before, and he says it doesn't use ammonia due to its toxicity although he didn't say what it does use. He also said it weighs 8 lbs so I take back what I said above, their is something new to it. Who ever wrote the article about it however didn't do a very good job.

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