
Air conditioner ‘in a patch’ provides portable cooling - modzu
https://www.nature.com/articles/d41586-019-01576-x
======
russellbeattie
I read an article [1] years ago about how exercising with a glove that had
coolant flowing through it enabled both athletes and regular exercisers to
have longer lasting sessions because they could cool down more efficiently.

Since then, I've thought that something like a simple strap for the hand which
had a copper plate for the palm and a bunch of heat dispersal fins like on a
GPU on back of the hand, with some sort of liquid running through it to help
pull out the heat would probably help quite a lot to help cool you down while
exercising...

1\. [https://news.stanford.edu/2017/12/27/cooling-glove-helps-
ath...](https://news.stanford.edu/2017/12/27/cooling-glove-helps-athletes-
patients/)

~~~
mcphage
I still think about this article. I was hoping to see some affordable product
to come out of it, but haven't seen anything yet.

Although... 2017? Hmm. I thought I remembered reading about it 5-10 years ago.
Maybe an earlier step in the research?

~~~
russellbeattie
Oh, yeah. they've been working on it for years [1]. You're probably thinking
about the same articles I am, from 2012 when all the blogs picked it up as
"better than steroids" [2]. I'm with you - I thought they'd have a consumer
product out by now. Also, there's some debate about whether this actually
works, but I did some personal testing years ago when I had access to a
treadmill and was able to jog longer with my hand cooled.

1\.
[https://www.sciencedaily.com/releases/2004/10/041006085310.h...](https://www.sciencedaily.com/releases/2004/10/041006085310.htm)

2\. [https://gizmodo.com/stanford-is-building-a-body-cooling-
glov...](https://gizmodo.com/stanford-is-building-a-body-cooling-glove-that-
might-wo-5939295)

~~~
mcphage
Yep, I bet that's it—thanks! :-)

------
m463
I remember reading an article years ago (wired?) where someone developed a
system to maintain a good body temperature in hot or cold.

I think the end result was a boot that lowered the pressure of the foot, then
circulated warm water against it. The person could stay in 32F water
indefinitely.

But the article also talked about core body temperature and exercise. High
core temperature was a limit on endurance. With a device to keep your core
body temperature even, you could basically exercise at high levels for long
periods of time.

I don't know why batman doesn't have something like this on his utility belt,
especially when he runs around in heavy black clothing on hot sunny days.

~~~
koube
I remember seeing articles about a glove version if anyone's interested:
[https://news.stanford.edu/2017/12/27/cooling-glove-helps-
ath...](https://news.stanford.edu/2017/12/27/cooling-glove-helps-athletes-
patients/)

~~~
L_226
One of the first things I do post training is stick both my wrists/hands under
cold running water. Works great

------
ernestipark
[https://embrlabs.com/](https://embrlabs.com/) has created a watch like device
that I think is the same idea.

~~~
anonuser123456
I believe these are distinct concepts. One cycles on/off to trick your body
into thinking it's not hot.

The other is just just pumping away heat.

Pumping away heat is probably better than fooling your brains thermoregulation
algorithms. But maybe heatstroke is your thing.

~~~
Wowfunhappy
I'd be fine with the latter if it also had a way to sense when you were
overdoing it, and either warn the user or disable itself.

------
rhombocombus
So a flexible peltier? I think peltiers are really interesting, they certainly
aren't very efficient, but I'm excited that innovation is happening in that
space. Heat pumps without moving parts will always be interesting to me.

~~~
deckar01
Heat pumps are more efficient than a compressor and are more effective than a
radiator. You could power it with a solar panel to get power when you need
cooling the most.

~~~
iancmceachern
A compressor is a heat pump. Peltiers are much much less efficient than
compressor driven heat pumps. Its why we don't really use them for much, but
use compressor a/c and refrigeration for everything.

~~~
londons_explore
Peltier units are used where compressors are too large or expensive.

For example, those $20 in-car cool boxes.

------
tristor
Interesting, this is a similar idea to whats been used in motorsports for
driver cooling systems for a long time. I just got in my new setup from
Chillout Systems [1] this week. Since I live in Texas, even many of the club
racers like myself invest in these types of systems since it's so hot here
during the Summer.

[1]: [https://www.chilloutsystems.com/](https://www.chilloutsystems.com/)

~~~
lowestprimate
We use to race here in CO (which gets hot but not as hot as Texas admittedly)
by dipping our Nomex suits in ice water and racing with ice bags in the suit
that leaked so two cooling mechanisms in action. Works for 45 mins. It was
great to get out with a completely dry suit after a race. Nothing like cool
balls during the race.

------
Aaronstotle
Being a large fan of the Dune novels, I'm looking forward to the day a
manufacturer creates a real world Stillsuit

~~~
inflatableDodo
I'm not looking forward to them being necessary, but given the news that bits
of the world may move past unaugmented survivability, due to wet bulb temp, I
have been giving some thought to the cheapest version. So far I have been
looking at a solar panelled conical hat, similar to the traditional chinese
farmer hats, with a curtain of layers of mosquito net. The layers are
seperated and cotain a water condenser that feeds to a storage tube at the
bottom that also acts as a weight and a cool environment is kept within the
circle under the hat by the air being blown through the condenser.

~~~
mLuby
If you had the cone made of slightly rotated PV strips within a stationary
brim and rotated them like a propeller hat you could do convention cooling in
an incredibly _stylish_ piece of headgear. X~D

~~~
inflatableDodo
Fantastic idea, you can also then cosplay as a jet engine.

I keep meaning to tidy up my design work for this and stick it online under
some sort of open source licence. I'm not sure what the best one is for
hardware projects, though the GPL will presumably do.

------
rkagerer
Is it basically just a Peltier cooler? I thought those things had terrible
efficiency?

~~~
klodolph
Yes, but you make up for the efficiency by cooling a single person, rather
than an entire room. At least, that is what it looks like.

------
CrispyBaby
Anyone have advice on staying cool at night? Now that it’s getting warmer I’m
having a hard time sleeping at night. I don’t want to just turn the air down
really low since others in my house wouldn’t like it. I don’t want to run a
fan all night either. This tech doesn’t really seem to be there yet

~~~
amalcon
What's the problem with running a fan all night? Legitimate question, as it's
never occurred to me not to do that in the warmer months.

~~~
indemnity
I also find the white noise from a fan helps me sleep...ymmv.

~~~
bobbob1921
sometimes i find even having a ceiling fan on low speed, slightly dries out my
eyes overnight/when I wake up in the morning. It may be all in my head, but I
seem to remember reading something that your eyes either flicker or don’t
always close all the way shut while sleeping. so no fan for me at night ( I
just generally keep other AC vents closed a tad so that more pressure comes
into my bedroom AC vent and i have thermostat thermostat schedule to be a few
degrees lower at night while I sleep, then a few degrees higher around an hour
or so before I need to wake up, the heat/warmer temp helps wake me up kind of
like an alarm clock )

------
londons_explore
I expected more from Nature.

The core of this device is a Peltier heat pump.

I'm sure it's great for keeping cool in the summer, but there is no way
they'll ever work out for cooling buildings. They're fundamentally inefficient
due to needing to be built of materials that conduct heat in one direction and
insulate in another, while simultaneously conducting electricity and having a
large bandgap. Such materials have not been found and are unlikely to exist.

Anyone technical proofing the article should have been aware of that, and
should not have allowed such claims to get into the article.

Single phase gas turbine refrigeration can theoretically get to the Carnot
efficiency limit, and in reality gets close to it.

~~~
aiyodev
You misread the article. They want to save energy by cooling the individual,
not the room.

> The use of such devices could reduce the _demand_ for energy to power
> central air conditioning by 20% in typical buildings, and enhance a wearer’s
> comfort outdoors, the authors say.

------
DenisM
I have embraced a large wet bandana on my forehead / neck / arm / etc.
Evaporative cooling for the price of $5 (and the effort of carrying around a
bottle of water). Dunno about 10C reduction, but it makes a lot of difference.
It also made me question the wisdom of having spent the prior years in
unnecessary suffering.

~~~
defertoreptar
Unfortunately that won't work for everyone. There are some places, where 90%
humidity is a regular occurrence.

~~~
DenisM
Good point, I was thinking mostly about Las Vegas when I typed that (have to
go there every year mid summer).

Well then, another contribution: a few years ago I have found that several
months of strenuous cargo exercise made me not care about heat, even the wet
heat. I would still sweat and all, but it wouldn't be nearly as bothersome as
it was earlier.

~~~
Causality1
The appropriateness of being a sweaty mess makes a big difference. Having a
big sweat circle on the back of your shirt in an office is more uncomfortable
than being soaked to the bone in your own back yard.

------
Skunkleton
What is the SWAP for this device? Not so interesting if it requires a large
battery.

------
krzat
It takes a lot of energy to heat/cool stuff. How much cooling could such
battery powered device provide? Is it even better than a cheap usb fan?

