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Self-Heating Can
nickprecision writes "Ontro has been working for a while, and they are about ready to get to the public market. Quite a nifty little self-heating can... imagine the uses. Read up so you know about it when your friends pull one out on the ski hill."
Self-heating cans were in use by the military during WWII!
Just a sidenote - in Europe (well - London) Nestle already sell similar cans of self heating coffee. Works quite well - shame about the taste of whats in the can though. I can't remember the reactants - but the oxidser is diluted hyrogen preoxide.
It looked like a nice idea, but I didn't try it - mainly because of the price: £1.30 IIRC, which is about $2. It seems a bit much IMHO for a normal cup of takeaway coffee, even if it does have a neat self-heating function! Good for camping trips, perhaps, but not in the roadside service station where they were selling it: you can buy normal fresh coffee for the same price and get a seat and newspaper to go with it...
http://www.dooyoo.co.uk/review/349432.html
As someone who did read the web site, I can say that the product they have produced, is virtually identical to the nescafe coffee cans other posters have mentioned.
According to the Ontro web site, they got the idea from similar products released in the early 1990s. Those ealry products had flaws, such a bulkiness, which Ontro wished to overcome.
Admitedly those early products (at least those released in the UK - there was a spate of self heating and self-cooling products released on a trial basis in the early 90s) did suffer from the flaws the Ontro founders identified. However, the product currently available from Nescafe, is a complete redesign of those early ideas, and has overcome the flaws in a very similar way to the Ontro product.
Ontro state that their product is 16oz in size, holding 10oz of beverage, and that it heats up within 5 minutes after pressing a button on the base, and stays warm for around 20 minutes.
The nescafe self-heating coffees are more or less the same size, stay warm for the same length of time, and heat up in around 3 minutes.
Nescafe and Ontro have produced solutions to the same problem, and ended up with very similar products.
I think that you should consider the fact that maybe, just maybe, some of the people who posted about the Nescafe products in the UK, actually did read the Ontro web site, and were commenting on the fact that the current UK product is virtually identical to the Ontro product and has been available for some time now, but is a different product to those available in the early nineties.
Personally I wish Ontro every success, as I would love to see the technology become more widespread (and cheaper), and I doubt that Nestle will take their product much further.
The one flaw that still remains (IMO), is the weight of the cans. They always feel as though there is some drink left, despite being empty.
www.vurt.co.uk
It's still around, I used it this thanksgiving to keep food warm. Little metal cans, probably packed at or near sea level judging by how, when opened at 7,000', the cap flies off and through the air, splattering flammable purple goo... oops.
I also understand the desperate alcoholic can squeeze it through a filter of some sort to get at the ethanol within... consult your local wino for exact directions.
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Benjamin Coates
The concept of a self-heating container is not new. Armed services personnel used a self-heating can introduced in 1939 that relied on the burning of cordite to provide the thermal energy.
I think all the recent self-heating mechanisms have relied on the reaction between calcium oxide (also called quick lime) and a water-based solution.
Actually, the Japanese had such can since the middle 1980's for cans of sake so the sake can be pre-warmed. I've seen them and they do work quite well.
Raymond in Mountain View, CA
The company Uniloy, who did the plastic molds etc for Ontro have this press release about the creation of the can. The PDF was released Dec of 2000. I'm still trying to find a full equation for how much heat is created by the Calcium Oxide (Lime) and Water reaction for given volumes. I'm just intrigued that they get a fast enough reaction from the lime and water... maybe they added some carbon dioxide to further drive the reaction? This would produce mortar (CaCO3) and water.
RudeDude
Perl/Linux/PHP hacker