

FlameStower - USB charger powered by fire - pisarzp
http://www.kickstarter.com/projects/flamestower/flamestower-charge-your-gear-with-fire

======
malandrew
I think they got the idea right, but designed it around the wrong source
first. Using fuel to power my devices means I need to carry more fuel with me.
Why do that when I can just carry cell phone backup batteries like this one:
[http://mylimeade.com/](http://mylimeade.com/)

Instead this should have been designed around something I can throw in a
campfire with some sort of protective spiral metal cabling to snake out of the
fire to a box with a USB connector. The metal cabling could be similar to
those used on high temperature oven thermometers.

~~~
shabble
The cable isn't likely to be the limiting feature here. The method of energy
conversion doesn't just require heat, it requires a _temperature gradient_
across the device. Here they're putting the tip in the fire to heat it, and
the little bowl at the back full of water is used to cool the other end, thus
getting a good temperature difference.

In contrast, throwing hte whole thing into the fire might work briefly while
the heating was uneven, and the water hadn't all boiled off, but as soon as it
reaches the same temp all over, no more power. And if it's all in the fire,
even the water evaporative cooling isn't going to help much, vs when it's out
of the direct flame/hot air stream at the edge.

I imagine you could design a in-fire version using a heatpipe to transfer
energy out to a radiator/cooler somewhere, but that would be much more fragile
and/or expensive.

What we really need is MEMS (or at least, really teeny, zero-maintenance)
Stirling engines :)

~~~
ori_b
MEMS (or stirling engines) don't help you there either -- as long as it's all
in the fire, you have trouble extracting energy.

All heat engines run off of a temperature gradient, which is limited by
Carnot's theorem to a maximum efficiency of (1 - Hot/Cold). If your heat
source temperature is the same as your heat sink temperature, you get zero
energy out of it.

The bigger the difference between the heat source and heat sink in your
engine, the more energy you can extract.

~~~
cnvogel
Fully agree, the only small remark being that it's

η = 1 - Tcold/Thot

and to put in perspective: If your metal rod on one side of the peltier
element (that's inside the device) is at 150°C = 302° = 423K and the cold side
(water reservoir) is at 20°C = 68°F = 293K the maximum achievable efficiency
is 30%.

In practice you'll waste a _lot_ of energy (probably the flame outputs about a
kilowatt of power, normally you'd comfortably use it to heat a kettle of water
or canned spaghetty or...) for a meager 2W or 3W of power to your cellphone.
That's because the energy transfer from a flame to a simple rod is very, very
inefficient.

------
nlh
First thought: "Awesome - power for phone if everything goes to hell."

Second thought: "Wait, if everything goes to hell, there's not going to be any
cell service."

Third thought: "Oh well, at least I'll have Candy Crush."

~~~
tesseractive
Perfect for using your offline cached copy of Wikipedia to recreate
civilization after the apocalypse?

~~~
bentcorner
Maybe? It'd probably harder than you think:
[https://www.youtube.com/watch?v=BVxOb8-d7Ic](https://www.youtube.com/watch?v=BVxOb8-d7Ic)

~~~
kazagistar
I think that is the whole point of bringing wikipedia along. Pretty sure you
could reconstruct most of civilization from it...

~~~
masklinn
Not sure, it's high on modern theoretical content but not very on low-tech
practicals, e.g. no information on how to go about prospecting for copper or
iron.

~~~
fsjkdjkgldgj
You won't need to prospect for iron or copper if civilization collapsed, the
fact of the matter is we could never be "bombed back to the stone age" as
there is soooo much processed iron just lying around - everywhere.

~~~
chris_mahan
We just need technicals on recycling and smelting, cooling, rolling,
machining, etc.

~~~
ballard
Myself and a couple other guys did the due-dillegence for a proposed
documentary about Stone Age to building a functional electric calculator.

The starting point would have various ores as they came from the Earth.

Glass and metal working are key.

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mpapi
I brought a BioLite stove with me on a recent camping trip and loved it. That
had other advantages: easy to get a fire going during a very rainy week, no
fuel to carry (in the White Mountain National Forest, anyway) and it was
pretty easy to cook with.

USB charging didn't seem all that useful at first, but with a USB-rechargeable
LED lantern it ended up being great. If that's all you really needed, you
could get it from the FlameStower without the battery + fan machinery of the
BioLite, I guess.

~~~
hellopat
I've been having an internal struggle regarding the purchase of a BioLite
stove. The primary reason I haven't is because of it's weight. As a
backpacker, the stove is just way too heavy to carry on a trip (weekend trips,
fine - but anything longer it would have to stay behind).

The FlameStower seems much more practical for longer trips because of it's
weight / bulk.

~~~
killerpopiller
[https://www.globetrotter.de/outdoor-kueche/sturmkocher-
spiri...](https://www.globetrotter.de/outdoor-kueche/sturmkocher-
spirituskocher/?q=kocher&listMode=grid)

well the Biolite seems to be a top notch stove plus it charges your devices.
The link above are comments of buyers, nearly all positive. For a stove you
prefer gas?

~~~
showerst
The biolite weights 33oz. My MSR pocket rocket weighs 3oz, + 2-8 oz for the
fuel. (I generally take 4oz for short trips). Even with an external battery
pack I could still be almost 1lb lighter than the biolite.

Biolite is totally cool, but 2lbs is a LOT for backpacking, you can get tents
lighter than that.

------
kalleboo
Last year there was the PowerPot, which is the same principle on the bottom of
a cooking pot [http://www.kickstarter.com/projects/david-toledo/the-
powerpo...](http://www.kickstarter.com/projects/david-toledo/the-powerpot)

~~~
queeerkopf
another similiar project:
[http://www.biolitestove.com/](http://www.biolitestove.com/)

~~~
freshhawk
I own one of these and it is fantastic, even if you don't use it to charge
your phone (which I do) you get to scavenge fuel instead of carrying it and
that vortex of flame boils water only slightly slower than most normal
portable camp stoves and it is just damn cool to look at.

~~~
mbubb
these are great - also good for starting campfires

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mfonda
Stoves with built-in USB chargers already exist as a commerical product. For
example, check out [http://www.rei.com/product/846334/biolite-wood-burning-
camps...](http://www.rei.com/product/846334/biolite-wood-burning-campstove)

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jpalomaki
A DIY version by Timo Noko [1]. The same guy has been tinkering also with some
other interesting stuff [2].

[1]
[http://www.youtube.com/watch?v=R1A5qc872Ks](http://www.youtube.com/watch?v=R1A5qc872Ks)
[2] [http://koti.welho.com/tnoko/](http://koti.welho.com/tnoko/)

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sgwil
And here I was hoping I could finally buy a USB powered flamethrower.

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jrochkind1
Oh man, I do and don't want to see the efficiency and carbon-output per joule
generated of this device compared to actual grid energy. Not to mention
particulate air pollution.

Although it will depend on what you are using for the source of your 'fire',
it's not gonna look good.

This is a weird idea.

~~~
NathanKP
It's not intended to be an efficient clean power source. It's intended for
people who want to do something like hike the Appalachian Trail and want to be
able to charge their devices using the same fire they use for cooking / heat.

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0xdeadbeefbabe
I'm going to get one so I can carry coal instead of batteries.

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hfsktr
Great for the post-apocalyptic world!

Maybe good for short term natural disasters or outdoorsy types who want to
stay connected.

I find some humor in that having a cell phone on and charged is still 'off the
grid' (I know they meant electrical grid).

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sbierwagen
I wrote about something very similar last year, the BioLite camp stove:
[https://bbot.org/blog/archives/2012/06/13/biolite_camp_stove...](https://bbot.org/blog/archives/2012/06/13/biolite_camp_stove/)
(I'd argue that the BioLite is a better product, despite being twice as
expensive, since it can run on wood.)

A problem with both products that they use the thermoelectric effect, which is
miserably inefficient: The BioLite generated 2 watts from a thermal power of
5500W, for a thermodynamic efficiency of 0.036%

Solar panels, on the other hand, don't need to burn anything at all.

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brandon272
I see this product as having two target markets:

1) Outdoorsy people who carry fuel and find themselvea away from electricity.

2) People who are going to burn their homes down trying to recharge their
iPhones during power outages.

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jebblue
It looks like something one could craft in Minecraft so I like it, seriously
though, I've been shopping for a solar charger just in case there is some
unforseeable disaster and I need to be able to keep the GPS and compass
working at least. This looks like a good alternative, I looked at two of the
competing products in the comments here but this one seems to me to keep the
most distance between the heat source and the electrical cord while still
staying out of the way of my cooking. The collapsible design seems like a good
idea too.

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Pxtl
2-3W? That means it's only a 0.5A, right? A lot of devices don't even charge
properly off of a 0.5A USB source.

~~~
pudquick
While they may not fast charge, many of the devices will trickle charge -
simply because the original USB 2.0 spec didn't require high amperage. In
fact, 2.0 spec allowed for a max of 5 'unit loads' with a unit load of 100 mA
(5x 100 mA = 0.5A). Putting out more than that was against spec unless the
port was specifically marked as a 'charging port' per the Battery Charging
specification (you may have noticed USB ports with battery icons next to
them).

It wasn't until USB 3.0 that the limits were increased. Additionally the
Battery Charging spec was re-written to increase limits for charging ports.

If you can plug your device into any single USB jack on a computer (not just
ones with a battery icon next to them) and it will charge, it will likely
charge with this project.

~~~
Pxtl
In my experience, 0.5A chargers (and PC USB ports) are functionally useless
for charging many modern smartphones and tablets, especially after a deep
discharge. There has been many times I've put on a device to charge on a 0.5A
source and come back to find its battery completely depleted. The charging
will fail to keep up with the device's idle energy consumption.

~~~
iguana
If your device uses more than 0.5A for idle energy consumption, your phone's
1500mAh battery would only last 3 hours. Standby time on most smartphones is
usually at least 12 hours, consuming between 100-200mA. Being able to turn the
device off, and charge for 3 hours while cooking dinner and hanging out around
the campfire is _awesome_.

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fudgy73
This, to me, isn't very novel. Why can't you just wait for the sun to come up
and carry a 140g solar panel? I suppose this may be useful in a very rare
emergency situation, but otherwise, nahhh.

$ don't lie, though, and it looks like they have almost reached their goal.

~~~
rom16384
It's not new at all, see this 1956 kerosene radio:
[http://blog.modernmechanix.com/kerosene-
radio/](http://blog.modernmechanix.com/kerosene-radio/)

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mmanfrin
Congrats to Adam (and Andy) -- went to elementary/middle/high school with him,
been neat to watch this product evolve over the past year on facebook.

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goshx
Does anyone bother to create something similar that would help 3rd world
electricity problems? oh, I forgot... they don't have smartphones.

~~~
c-oreills
Biolite does this. Traditional stoves produce a huge amount of smoke which is
bad for people breathing it. BioLite reduces the smoke, but they found that
men were usually in charge of purchasing decisions and weren't around when
cooking was being done, so had no incentive to invest in the smokeless stoves.
Adding electricity to the stove meant that men were more likely to buy, thus
helping their family's health.

[http://www.bbc.co.uk/news/business-24116000](http://www.bbc.co.uk/news/business-24116000)

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lafar6502
a superior technology is known for several years, but still can't make ends
meet

[http://www.forbes.com/sites/michaelkanellos/2013/01/31/why-a...](http://www.forbes.com/sites/michaelkanellos/2013/01/31/why-
are-portable-fuel-cells-such-a-flop/)

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fnordfnordfnord
Mongolians will love this.

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wavesounds
I like it but I'm curious how this compares to a hand crank like on one laptop
per child

~~~
diydsp
Handpower delivers about max 20W per hand to a bike with both hands. With
electromechanical efficiency, 20W per hand comes out to around 1-10W per hand,
depending on hand speed and generator efficiency. [1]
[http://www.amazon.com/Bicycling-Science-David-Gordon-
Wilson/...](http://www.amazon.com/Bicycling-Science-David-Gordon-
Wilson/dp/0262731541) [2]
[http://dspace.mit.edu/handle/1721.1/69801](http://dspace.mit.edu/handle/1721.1/69801)

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corresation
Of limited practical use, but I can see it being a hot present for outdoorsy
people.

~~~
orenB
I don't agree. In Africa where not all ppl have access to the electricity grid
it have practical use. Together with google internet balloons plan it might be
a game changer.

~~~
ctdonath
BioLite is making a generator/stove for daily home use in 3rd World
conditions:
[http://www.biolitestove.com/homestove/overview/](http://www.biolitestove.com/homestove/overview/)

They also have a camping version: [http://www.biolitestove.com/campstove/camp-
overview/features...](http://www.biolitestove.com/campstove/camp-
overview/features/)

~~~
orenB
In a quick look it seems like the same product with different marketing slogan

~~~
zdw
Biolite appears to have been formed in 2009, so much before this product:
[http://en.wikipedia.org/wiki/BioLite](http://en.wikipedia.org/wiki/BioLite)

The tech used in either of these
([http://en.wikipedia.org/wiki/Peltier_effect](http://en.wikipedia.org/wiki/Peltier_effect))
has been known of since the 1800's - in the tech world we usually see it
applied to exotic cooling solutions for microprocessors.

~~~
shabble

        <pedant>
    

Strictly speaking it's not the Peltier effect, but the Seebeck effect. One is
the inverse of the other; Peltier junctions produce a temperature gradient
when current is passed through, and Seebeck ones generate a current when
exposed to a temperature gradient.

I think for the most part you can actually run either type in either mode, but
the design and materials differ for optimal efficiency across the 2 modes.

