Rachel does a lot of writing, so I thought I would help her out today by showing you a thing she found that she seems to be pretty excited about.
She’s talking about Coffee Joulies! What’s a Coffee Joulies, you ask? It is this:
“Phase Change Material” that is designed to melt and absorb excess energy until it reaches 140°F. At that point, the material begins to release the stored energy, thus maintaining the temperature of the coffee.
You just put them in your hot beverage and your hot beverage will cool down to an acceptable sipping temperature without becoming too cold, and it’ll stay that way for hours. Whoa that’s neat. You can pre-order a set from the Coffee Joulies Kickstarter page! Thanks, Rachel! I love you.

this is a thing you can pre-order
I was also pretty excited to discover those via Rachel’s tweet. I mean, my coffee just always gets cold.
OMG. OMG. OMG. OMG. OMG. OMG. OMG. O.M.G.
I saw these too today and I want them BAD!
full disclosure: initially found out about those via laura’s shared things on google reader. high five laura!
and they’re pretty!
i have no clue the science behind these little gems but they are so so cool.
I’m a liberal arts major, so take the following with a coffee bean of doubt, but here goes:
Despite their touting it as a marvel of science, it’s just harnessing the everyday business of phase change. My totally haphazard guess (but probably correct) is that there is a mass of paraffin (or another type, perhaps even a blend) wax inside these stainless steel babies. At room temp of 22-23 degrees Celsius, paraffin is solid.
Paraffin wax however, would melt in the neighborhood of 47-64C or 117-147F according to wiki. A bit of googling suggests that drinkable temp for a beverage is in the neighborhood of 55-60C or 131-140F. The specific heats of paraffin and water aren’t so far off, but the lack of stainless steel estimates online is annoying (also I can’t seem to figure out how much these things weigh so I can’t do the Q=mcdeltaT)… but I digress…
That being said, when a substance is in a solid state the atoms inside it are moving very little, vibrating a bit, but they get more active the hotter they get. Thermal energy gets converted to kinetic energy at the molecular level. (If there are science people up in here, stop me now because I’m probably wrong but..) Anyways, the point is that if you drop one of these room temp 23C Joulies into your tea/coffee situation at 100C, it undergoes quite rapidly a 37degree temperature delta. Because stainless steel and paraffin wax are excellent conductors of electrical and thermal energy, their uptake of this extra environmental energy would be quite rapid, hence the 2x faster cooling period. The wax inside would therefore melt and become liquid.
The phase change is reversed then, as the outside temperature of your tea/coffee situation decreases as its remaining heat diffuses into the environment, i.e. your chilly body and/or if you are drinking this beverage in a meat freezer, as you do. Anyway, the point is that the extra energy these little Joulies have taken in to melt the theorized wax inside is slowly being released back into your beverage, i.e. the wax is becoming solid again.
TL;DR: this picture sums it up
if your reply did not include a picture, i would have turned the proverbial page.
HOWEVER – instead i totally read it. and i feel like alton brown needs to have an episode re: this.
wax, in the…& steel ball bearings…for coffee… Q=mcdeltaT? #omgMATH #nerdcrush
now you’ve got me worried that i did liberal arts wrong.
i want your toes so badly right now. #nerdcrush
Who knew there was more to witty comments to terra…etc. Nice lady! i’m impressed and moderately turned on!
reading this was even more exciting than the actual coffee things, just saying. #nerdcrushTOTHEMAX
You’re a genius, I somehow actually understood all of that and I know nothing or next to nothing about physics or chemistry or whatever science it is that’s involved in this
RIGHT?
Aw you guys. :nerdblush:
I’m glad you enjoyed my post. I’m not all puns. But I mean, I am still at least 90% puns.
You had me at Q=mcdeltaT
bahaha i love that you started out by proclaiming you’re a liberal arts major. way to be. mucho points
these are so brilliant! reminds me of whiskey stones (chill whiskey without watering it down)
I just hope the word “melt” was a typo…
ah, ok, the melting stuff is contained – it sounded worse than it was for a second!
Initially I read “whiskey stoned” and thought hey, that was basically my weekend.
Also, your name is quite appropriate.
hahah yes to all
these are whiskey stones if you want to be (whiskey stoned)^2
http://www.uncommongoods.com/product/whiskey-stones-gift-set
If whiskey is involved I like it
this basically = my life mantra.
THERMODYNAMIC AND CHEMICAL PROPERTIES FOR THE WIN. and people don’t believe me when I say physics changes the way we live our lives…
i feel like id forget and end up swallowing all of them eventually…
I am so glad to see I’m not alone in this feeling.
My thoughts went, “Woah! This is so cool!” to, “Oh god, I’d probably accidentally eat them!” almost instantaneously.
They’re pretty big, though! They look teeny in the pic above, but much larger in the video at the link.
oh but they are still pretty awesome~!
can you reuse these? WILL I DIE?! quiero…
It looks like they’re not only reusable, but machine washable! *swooon*
I would be ALL OVER THIS… if they didn’t retail for $50. That is more than a week’s groceries. That is two guitar pedals. That’s the super deluxe new An Horse Walls bundle with the a CD, signed poster, LP, and pillowcase AND $10 left over to buy about 7 cups of coffee from a locally owned coffee shop.
But if I had money, these things would be so frigging awesome.
i kind of felt that way but then i had to stop for gas on the way home and thought “they are the same price as a tank of gas basically!” and i fucking hate buying gas so i thought it would actually feel good to buy them, like HA here is $40 i am spending on something awesome that is not a fossil fuel.
also if you buy them in the next 6 days through kickstarter they’re $40. also i’m asking for them for my birthday/christmas. so.
Yea that’s true, and if you drink a lot of coffee it would be totally worth it. Maybe next year in the dead of winter I will once again think of this product fondly when my hot tea gets cold within 15 minutes.
Do not forget the free trade coffee beans or tea leaves. Free trade is a wonderful thing.
I love physics. So cool!!
OMG! Completely want these super bad. I reheat my tea/coffee a zillion times throughout the day cause I drink it so slow and they just moved the microwave in my office to somewhere far away/where I can’t find it. seriously amazing.
Drink tea from a bowl
I’m sorry, that is not really related
A cup tea never makes it past fifteen minutes when I’m around. But I bet I could use them to keep a large pot of tea warm for hours…This is the greatest thing ever
My life will never be the same.
DO WANT.
WANT SO BADLY. I’m really bad about drinking tea or coffee because it’s too hot so I let it sit, but then I forget about it and it gets too cold. SO this is perfect.
I emailed all my coffee f(r)iends and one of them emailed me this:
—
An interesting concept, but quite literally, the same thing happens with a rock or anything that has a mass to absorb heat. The concept of the “it freezes on the inside at 140 degrees” is cool and obviously their selling point, but a basic understanding of the law of conservation of energy says that it changing its state of matter (liquid back to solid) isn’t going to do anything special in terms of the transfer of energy. I just called my thermodynamics friend to confirm this… there’s nothing special about that transitional point in terms of its exothermic reaction; it’s not as if when something hits its freezing point it gives off a disproportionate amount of heat. In that sense, something that would be more effective would be something that would have a higher rate of thermal conductivity (i.e. – copper), but then you’re just putting pennies in your coffee, and that doesn’t sound very cool.
—
This makes me very sad. Rebuttals? :(
I still want. My birthday is May 7th. Just sayin…
I don’t even need my coffee to stay hot for hours. 40 min will do!