A couple of engineer buddies have designed the latest must-have accessory for the coffee drinker. Joulies are metallic beans you drop into your hot cup of coffee to make it exactly 140 degrees. They haven't even been manufactured yet, but already the project has accumulated some $35,000 in Kickstarter cash. I guess a lot of people are tired of blistered tongues.
Each Joulie is a small metal shell filled with a phase-change material that melts at 140º Fahrenheit. (Some people might prefer 155º -- perhaps there will be a version for us.) So the Joulies absorb heat from the coffee till they reach 140º, and then start emitting heat. The effect (if you put in enough Joulies for your volume of beverage) is to maintain the coffee at the desired temperature for long enough to savor it. Using an insulated cup is recommended also.
We've seen this idea before, in the form of Fraunhofer's Perfect Coffee Mug, but this time it seems poised to actually come out of the lab and into your cup.
Interesting use of phase changing materials.
I hope the material is inert or has some distinguishing taste to it in the event that there is a leak.
To get the right temperature of my tea, I simply add two ice cubes, then gulp it down right away. I've never acquired the taste for coffee.
Someone should come out with a battery powered coffee mug similar to an electric kettle, but smaller of course. It sits in a charging rack and you just pull it out, put water in it and it reaches temperature you want. Li-ion and Li-Poly batteries should make this viable. The charging pad could be a USB plugin that sits on your desk like a beer pad or coaster.
How can I get some of this Kickstarter cash???
Nice practical application of thermodynamics. It could also function as teaching tool to help explain equilibrium and entropy.
However, looking at it from another perspective, what kind of warning label can be associated with the product so that when someone accidently swallows one the producers are not open for a lawsuit?
All4it- To answer your comment "I hope the material is inert or has some distinguishing taste to it in the event that there is a leak."
Check the faq at http://www.kickstarter.com/projects/705847536/coffee-joulies-your-coffee-just-right
"Joulies are filled with a proprietary substance called a “Phase Change Material” (PCM) that melts at 140°F and is 100% edible food-grade magic."
I dunno, I think 140 is too damn hot.
what if i want my coffee to be liquid at 140C?
Those kinds of coffee mugs exist.