USB Charger Solves Mongolia Electricity Problem


People living in remote areas of Mongolia do not have access to electricity or gas, and rely on traditional wood stoves for their homes, which are used almost all the time. Many use solar panels to generate some electricity for small tools, but unfortunately there are often times when it is cloudy for days on end. [Chingun Has] saw this problem and created his own clever solution — a small thermoelectric USB charger.

[Chingun’s] device features an array of peltier plates inside of an aluminum shroud. The device is designed to sit on top of a stove, or to be strapped onto a stove pipe. When there is a large enough temperature differential between the two sides of a peltier plate, a charge is induced. He’s using a small fan to help cool the other side of the peltier plates. A small control box houses a voltage regulator circuit that provides 5V over USB.

The cool thing about this project is that it is partially the result of [Tony Kim], an MIT professor who traveled to Mongolia to teach students an edX circuits course about a year ago. [Chingun] was one of his students, and this is a great example of a solution to a real-world problem.

An excellent video after the break gives a complete explanation of the project, as detailed by [Chingun] himself — it’s well worth the watch!

[Thanks for the tip Greg!]

47 thoughts on “USB Charger Solves Mongolia Electricity Problem

  1. This will be far more effective if the ‘cool’ side of the peltiers have actual heatsinks to remove the heat. Using them bare will drastically decrease power output since they provide power based on the differential.

      1. Better, keep them cool with running water. Anything that slows the escape of heat from the heatsink is robbing this of power.

        What WOULD be better is, rather than using Peltiers, which are horribly expensive per watt, and not rated to run at those sort of temperatures, is to build proper thermocouples. Or even better invent a practical easy way to make thermocouples from scrap metal with simple tools, or perhaps even a new tool he invents.

        It’d be infinitely cheaper, needing just common metals, robust to the point of indestructible, and practical in a country that doesn’t have semicondcuctor plants or whatever rare elements.

        Thermocouple generators have been done for a long time, people mentioned here before the famous Russian one that ran a radio from an oil lamp.

        So 1/10 for the implementation, really, though the idea in principle is very decent and helpful to people who need it. The fan and USB options are good, just the power source needs fixing.

          1. I posted the animal powered treadmill because I believe it’s old tech that still could be used to make the every day lives of many, but it never occurred to me to dismiss this builder or MIT because their lack of knowledge of old tech. All I expect universities to teach there engineers is how make use better use of current technology or how to discover new technology. There isn’t enough time in the day nor the brain capacity in the average human to tech and retain all of history.

          2. @Static

            Therein lies the problem. We, as a human race, spend quite a bit of time reinventing the wheel for a variety of reasons. Usually because no records of prior achievements are readily available or accessible. But this is the day and of age of the internet there is absolutely no need to retain all of history. We have a repository of knowledge exceeding that of Alexandria coupled with a, normally, cooperative collective that has the ability to disseminate new information into the old and a number of search engines to sift through all of that.

            There’s been more than a few times I spent trying to tackle a particular problem only to pick up a solution from an old tech document thirty or more years old.

          3. And to be fair, I haven’t been to MIT and I know what they are. I’m not old. Most people here have heard of them. Thermopiles really aren’t a secret, as the site Dana pointed to shows.

            Even looking up peltiers on Wikipedia leads to Seebeck effect, which leads to thermocouple and thermopile if you look hard enough.

            This generator is a Youtube-quality project, from someone who doesn’t know the basic principles, who goes to MIT, possibly the most advanced source of technological knowledge on the planet. I think it’s reasonable to be surprised and disappointed.

            And as Savannah points out, there’s often a simpler, better solution already been discovered, then abandoned.

          4. re-read again.

            >The cool thing about this project is that it is partially the result of [Tony Kim], an MIT professor who traveled to Mongolia to teach students an edX circuits course about a year ago. [Chingun] was one of his students, and this is a great example of a solution to a real-world problem.

            The professor went there a year ago to teach a specific course.
            nowhere is it quoted that any professor (MIT or otherwise) thought that this was the right way to do something.

            The Hackaday author says this is a great example of a solution to a real world problem.

            and it is exactly that.

            there is a real world problem (no electricity to power mobile devices) the existing solution (solar) isn’t good enough, and this is an example of a solution that uses waste heat to generate electricity.

            no, it’s not technically the “best solution” but it is a great example of “a” solution.

            never mind what they are teaching at MIT, it seems that reading comprehension needs to be taught more thoroughly in some places.

        1. DIY thermocouples aren’t that hard, twist together 2 wires, run them over with an oxy-acetylene torch (I’d presume those being abundant in various shops there, since they have problems with not having electricity) and voila…now you just need to do about 499 more to get any decent power :D

          1. I’ve been reading more about it. From the Victorian era thermopiles (ie an array of thermocouples) were all over the place! Up until mains electricity spread, people would use them to charge batteries, or power radios directly, many gave a dual output for the high-tension tube supply, and the low-voltage cathode heater. Powered by gas (the gaseous kind, not -oline).

            This is a technology that was massively succesful. For the small amounts of power needed for radios, since there wasn’t much else electrical, they were practical where a generator with moving parts wouldn’t have been.

            This is really a solved problem that people seem to have forgotten about for 70 or so years. While so much effort goes into giving poor countries expensive solar panels and maintenance-needing wind generators, something completely solid, powered by our first invention, fire, has been sat in museums.

            I’d like to hear a good reason why this isn’t used much more. The metal alloys are cheap and you don’t need much of them for a household supply of maybe 50 or 100W. Has it really just been forgotten? If you power them with wood, dung, or charcoal, they’re carbon-neutral.

            Youtube is full of people hooking up Peltiers to things, but they’re Doing It Wrong! A day or two twisting wires gives so much more a robust, reliable and high-power solution, that’s cheap too.

            Perhaps I should drop the United Nations, or Oxfam or somebody, an email.

        2. So this uses the same power source as the thermocouple you are promoting. Fact of the matter is thermoelectric generation was at a dead end until the solid state devices where developed. That oil lamp/ thermocouple powered radio did go anywhere neither did a host of thermocouple based thermoelectric generators. A thermo electric generator constructed using home shop constructed thermocouples using commonnly available scrap metal couple of producing this much power is going to be of an unwieldy physical size to the point it would be impractical. True the modules used aren’t designed for this use, and there a videos showing them failing miserably and this builder admitted he had failure early on. I don’t know what resources Mongolia has or doesn’t have, but I have see a peltier devices described as being made in the USA, by your logic I should never use on, if can afford one, just use outdated technology, technology that never wasn’t ever widespread if I want a thermoelectric generator.

          1. While you can afford peltiers, and order as many as you like, made in the USA as they are, unfortunately a lot of people don’t actually live in the USA. Or else they’d just plug their stuff into a wall like everybody else.

            Peltiers just don’t seem to be practical for energy generation, there are so many stories on this page alone of failure, and most of these people are pretty bright and knowledgeable!

            What do you mean by “unwieldy” and “impractical”? As I mentioned, thermopiles were used massively before mains electricity. They were fairly compact, and very practical. While making one from scrap would be perhaps bigger and less efficient, does it matter? Scrap is something poor countries have a lot of. Particularly compared to doped silicon and ISO-grade clean rooms.

            Crack a way to make thermopiles from scrap, in a way ordinary people could be taught to do, and you’d be a long way to solving a massive problem. Doesn’t matter if they’re big and ugly. If they can be made from what’s available, run on what fuel’s available, then they’re revolutionary. Importing first-world technology is just what doesn’t work in the third-world. They need stuff they can make themselves with the tech and materials available there, not rely on expensive donations that could never serve any great amount of people.

            There’s a lot of tech the West thrived with for a long time, and perhaps the Eastern Bloc used for even longer. We don’t use it any more, but it was good enough to get us where we are with what we had.

  2. With the “cold” side so close to the heat source I has surprised to see it work. Perhaps in that location a thermosiphon to pump the heat outdoors. Possibly add more life to modules not designed manufactured for this use, allowing more modules used to charge a battery bank for LED lighting a small television etc., assuming they could afford anything more than LED, but they have a cell phone though. Along with a bit more engineering provide the luxury of gravity flow hot water. On seeing the critter they may be overlooking an obvious power source on still used by some in the USA.

  3. Also thinking, I wonder if one could run a cheap Indian 2-stroke motorbike engine from producer gas? You need steam and charcoal, it gives CO, H2, and CH4 as well as non-useful output. People ran cards on it during WWII when petrol was rationed, I’ve seen a pic of a car with a giant balloon-type bag on the roof, full of gas, while the gas generator in the boot (trunk) made more. Doesn’t need much modification of the engine.

    That might be a solution. The same reaction essentially gave the towns of Britain gas for cooking and heating, using coke (purified coal) as a source. This was before we discovered gas and oil in the North Sea, and it powered a country. Sure plenty of other countries had “gas works” in the past, before natural gas took over. Coal would help but charcoal will do for small-scale production, for low-power equipment, LED lights and phone / tablet charging.

      1. See, that’s what they need! Made pretty much out of ordinary metal, produces tons of useful stuff out of wood, which is everywhere! Or I suppose bamboo or whatever grows in the mountains that most of Mongolia is made of. I know home gasifiers need a bit of tweaking, this is something that a bit of research would be well used for.

    1. I’d think engine lubrication could be a sticking point on running a stroke on producer gas although there where/(still are?) two cycle engines that used oil injection into the crankcase to avoid premixing the fuel. With Ajax stationary two cycle engines the crankcase is lubricated in the same manner a four cycle engine is, but the cylinder is lubricate by a pump that injects oil directly at the piston travel. No doubt the smaller two cycle engines could be made to run on producer gas if the base fuel is available to make experimenting to do so worthwhile.

      1. Ah well, it’s just an idea, since I know India for one has quite a big industry making engines for motorbikes and tuk-tuks, with all sorts of terrifying combinations of entire families riding on small bikes! They really push their engines, so they must make them well.

        Recently the news has mentioned the idea of Indian-made cars, with proper 4-stroke engines, being sold in Western countries, so they’re obviously getting there fast. Maybe that would be better, perhaps for a village to have a central building for a producer-gas generator. Unless it’s simpler to use steam engines. It’s a matter of getting what they need, from what they have. Ingenuity counts for a lot where there’s not a lot of money.

  4. Wow, a whole country powered by a USB charger, that’s impressive! But then again it is Mongolia. Anyway it seems to me that if he attached the peltiers to the chimney OUTSIDE the geer and put big ass heat sinks on it he would get much more power do to the greater temperature difference than inside.

    1. One imagines there’s plenty of snow and running water in Mongolia, to do the cooling. As a combined water-heater and plumbing exercise, you could probably kill a lot of birds with a somewhat more complicated stone.

  5. Maybe driving a stirling engine from the heat from the exhaust would be more practical? Sure direct electricity conversion is a good idea, but cost wise its pretty high compared to old fashioned heat->movement->electricity conversion the world uses… otherwise we would be using this kind of thing in power stations rather than steam turbines…

    1. It’s highly inefficient, yes, but there are no moving parts*, making it an easy, inexpensive, low maintenance way of generating electricity from heat you’re already using to heat your house. Once the simple generator is made and installed, there’s effectively zero marginal cost of using it.

      We should really all have furnaces that power themselves using the heat that they generate. This would allow people to keep their homes heated during power outages.

      * No moving parts, that is, unless you use a fan to cool the cold side side of the plate, as Chingun Has did.

    2. My thoughts exactly, but I’m not experienced enough to know the efficiencies of both methods. All I know is that Stirling engines have low torque, but high speeds, so if one uses a toy DC motor as generator it might get a milliwatt out of it…

      Chingun used a linear regulator probably because he didn’t know about switch-mode or it was just a proof of concept, but this part can be improved a lot in the next iterations.

  6. Chingun, please ignore the know-it-alls. This is a great solution using minimal parts to provide a very practical solution to a real-world problem. Keep up the great work!

    It’s about 100 times easier to nit-pick somebody else’s work than it is to … actually do something productive.

    I would be really interested to know how much current this can produce.

    1. Not meaning to nit-pick, but it’s not a practical solution. How many Mongolians can afford peltier chips, and where the hell would they order them from? There’s also the issue of the solder melting and the chip falling apart at too high a temperature,

      I just suggested what I think’s a better method for it. The idea is good, using fire to make small amounts of power locally in poor countries. The peltier is the wrong bit. I’m surprised he wouldn’t know that. That’s all!

    1. I LOVE the way they point out 3 billion people need electricity, and show so many big pictures on their site of all the poor people who could, for just $129.95, have themselves a solution to charging their Iphones at last! A company called Powerpot sell a camping saucepan that does the same thing. There’s dozens of companies selling thermo generators at completely unattainable prices for the third world, while somehow claiming they have a solution. Is it just to make people feel better about buying expensive toys they don’t need to go camping?

  7. Just to clarify for those who might think the whole of Mongolia is living in the past… this guy had to travel quite some distance to find such a ‘traditional’ house and it’s not a typical living condition for the ‘average’ Mongolian.

    It’s a cool idea but I think improvements could be made. I’ve made similar before and with big heat sinks and larger fans I still managed to burn out the peltier extremely quickly. So I highly doubt his are going to last long with that tiny little fan and no heat sink. Ideally you want to get water on the ‘cool’ side since it has a max temperature that it can reach. A pan with good heat transfer properties and full of water will work well. Obviously this limits the mounting options though and you do have to top up the water now and then.

    I know this kind of thing has been featured before on HaD and is available in commercial applications like the biolite stove but I’m still happy to see it shown in a ‘practical real world’ way. Even if it still needs some tweaks.

    1. Fair enough, tho there’s still plenty of people living in shacks and shanties around the world even if they aren’t Mongolian.

      As you point out tho, a peltier isn’t a practical solution. And Youtube shows there’s a hundred people who’ve wired them up to provide power for stuff. It’s a novelty, tho it’s not actually novel, and that’s all. The third-world angle is some sort of social whitewashing to make a silly vanity project seem worthy.

  8. Neat idea, but it is incredibly inefficient. more than 1/2 the power being generated is lost in that 7805 regulator. he needs to use a far higher efficiency DC-DC converter, but I am guessing that this is simply a proof of concept design.

    This could certainly become an awesome device that could be over the top rugged. he just needs to source high temperature wires and high temperature wire sleeving as well as finding a way to make the whole thing far more robust so that it can be thrown around carelessly and not be damaged. I recommend also adding a nice handle on the top.

  9. I hope one day to be able to visit Hack a Day and not just read peoples whining and nit picking about every little detail of a hack. It wasn’t like that a few year ago and I dislike this wave of negativity on a site that should really be about cooperation and sharing.

    1. At least most of the ‘whines’ include tips and suggestions about how to do things differently. Maybe if some HaD authors could stop their poor writing then people wouldn’t be so pissed by the time they get to the comments lol.

      Cheers to Mongolias electricity problem!

  10. This looks really interesting. Does anyone know how much power a common peltier plate will put out? Or for that matter how much a single Seebeck thermocouple can put out?

    I always assumed the power wasn’t enough to be worth the effort. (Insert old saw about assumptions …)

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