Indie Project Corner: Charge Your iPhone Over a Campfire

The FlameStower Fire Charger  ($99) made me a little nervous when I first pulled it from the box and set it up. It's the brainchild of two Stanford students, Adam Kell and Andrew Byrnes. The contraption looks like something featured on MythBusters, but this weird-looking stand can actually kick out a 2.5W charge to your iPhone with nothing more than the primitive elements of fire and water (it also purifies the water in the process). Great for emergency or camping kits. How does the Fire Charger (or the in-home Candle Charger version) do it? 

The science behind the fire-water apparatus used in these products lies in a thermoelectric module called a Peltier cooler. A Peltier cooler works by exposing temperature gradients to varying semi conductive metal surfaces, which can thereby produce an electrical current. This is a fancy, "science-fied" way of saying that making one side of a special metal surface hot, while keeping the other relatively cooler will produce electricity that can juice up your cell phone. Back in 1821, a German physicist named Thomas Johann Seeback first observed this phenomenon while conducting experiments on dissimilar semiconducting metals (though he thought it a form of magnetism-source Wikipedia). While that's pretty cool in and of itself, it doesn't get you all the way to a stable and mobile power source from fire and water. To do that you need both the proper materials science and a smart and efficient power conditioning module.

Adam and Andrew (both founders of Stower) became obsessed with the notion of generating power in conditions where access to the grid is limited (natural disasters, campsites, on safari, etc). Both were materials scientists studying at Stanford, and had been concentrating on solar and alternative sources of producing power. Through their course of study and endeavors to come up with a high quality yet portable solution, the idea for the FlameStower was born. Though the fire and water electrical current concept was not a new one, they set out to create a safe and easy-to-use product using the science. The result is a stand-like contraption with a sort of weird looking, collapsible rubber container on top (you put the water in there). A smart circuit converts the current into something suitable for a mobile device.

The Fire Charger (already a successfully Kickstarted product) seemed to be a little wobbly which made me hesitate to test it inside the house, so I used it in the garage on the initial test runs. It isn't just that fire is involved (though that is important) the surface of the metal of course is going to get hot. This also brings up safety concerns about the product itself. Both the Fire Charger and Candle Charger are stands. Stands are notoriously easy to knock over, particularly for young kids; which means there is a hazard of getting burned, and if the stand fell into something extremely flammable, a serious fire could result. So, some basic safety precautions should be followed (like not using the device where young kids might be able to grab them). In my testing, I kept a fire extinguisher close just in case, though I didn't have any problems except some annoying fiddling with the FlameStower stand to keep it upright and level. I was assured that the products are stringently safety tested.

The Candle Charger resembles a fondue pot, but the concept of how you use either product is identical. Once assembled, fire is added below, and water goes into the container above. A USB wire/dongle hanging out of the gadget has a ready light that informs you when it is ready to provide a charge. It blinks first and then goes steady when it's fully ready for use. Stower sent a can of Sterno to produce a flame to test with. I could not get the Fire Starter to charge my iPhone, though the light weakly illuminated after around 20 minutes of applying heat. I tested the metals temperature along the fork-like tine and believe it was just not able to get hot enough (it was designed to be used in a campfire). I let it heat like that for around 30 minutes before giving up. The candle charger, in contrast, lit up like a Christmas tree almost as soon as I applied the flame, and within five minutes I was charging my phone. The current is something close to that of a laptop USB port, so it will take more time to get a full charge than it would from a standard outlet. The Fire Starter specs say an approximate 45-minute charging period can be achieved on each water refill.


  • Charge your devices using just fire and water.


  • Fire (or extreme heat) is required.

Final Verdict

This is an insanely cool idea—with science, experience and perseverance, Alex and Andrew created something of technical quality that is also truly practical for humankind. It also demonstrates that you can never tell where the next great idea might come from (so if you have one, don't give up on it). Now for some minor criticisms: I think the Flame Stower could use a little reinforcement on the frame side. It had a tendency to tip forward (even after I tightened the thumbscrew to prevent that) and seemed a little wobbly on my basement floor (which is admittedly not going to be the normal use case, so I will cut it some slack there). It was designed to be light and portable, after all. The Candle Charger (which can be had for $65 on pre-order at Kickstarter) worked exactly as advertised and gets full accolades for being a sturdy and functional charging alternative also safe to use around the home (provided some basic precautions are followed).

Top image credit: Photo Image /

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Author Details

Nate Adcock's picture

Author Details

Nate Adcock

Nate Adcock is a system and integration engineer with experience managing and administering a variety of computing environments. He has worked extensively with mobile gadgets of all shapes and sizes for many years. He is also a former military weather forecaster. Nate is a regular contributor for the and blogs and helps manage both websites. Read more from Nate at or e-mail him at