Biolite CampStove $129
Power Practical PowerPot 5w/10w & Lithium 4400 Battery Bank $99-$149
Tegmart Devil Watt – 10w/15w Open Flame Generator $235-$304
TegMart Devil Watt – Woodstove Generators 15w – 100w $234-$725
Thermoelectric generators are not a new technology. “TEG” power was discovered in 1821, but I have to admit, it is new to me. I recently discovered three consumer products that create electricity from direct heat, and all three of them have survival applications. One of them is the best bugout or camp stove I have ever encountered, and I would take it one step further and say that it is the best bugout cooking solution I have ever encountered, period. A second is made for generating electricity while you cook your dinner, and I had marginal success with it. The third is made for a high level of direct heat electricity production, and you can drive it from your rocket stove, a camp stove, and they have models from 10 watts up to 100 watts that use waste heat from your wood stove.
I would split these up into three articles if I didn’t believe that time may be getting short, and that survival budgets are full of hard choices. Please check out all three of these great products and decide which fits your needs the best. I have yet to do my “survival computing” article, but if you check out the material we have already covered, just being able to charge your smartphone can give you a cheap geiger counter, an off-grid topo-gps, and even a worldwide (SDR) radio. The other day I found some apps that generate and read Morse code, and if you want to “talk” to loved ones across the continent or across the world in a grid down situation, Morse code, or “CW,” is most likely going to be the way you’ll do it on the cheap. Yes I have an article explaining that coming, but if you are handy with soldering electronics, search Ebay for “qrp transceiver” and get going. Being able to charge your phone, and even a big 12v storage battery, are really possible with these TEG generators, so don’t take them lightly.
The Biolite CampStove
If you have read this column for the last year and a half, you know that I am a huge fan of the “Rocket Stove.” The Rocket Stove concept is somewhat complex. The best way I can describe it is that as wood and other biomass like leaves burn, they heat everything else in the stove at the same time. This releases volatile gasses, that in an open campfire, mostly don’t burn, and just float off. In a Rocket Stove, the gasses are trapped in an insulated, superheated chamber and forced to burn. This gives you an unprecedented amount of BTUs from a very small amount of fuel. In practice, that adds up to cooking dinner from a handful of sticks. To give you an idea of my practical experience, all of the Rocket Stove articles I have done here just on this article used up what was a small armload of dead branches, many of them half eaten by bugs.
My tribulations with the Rocket Stove have been getting the thing lit and burning good, because I insist on using wood and leaves that have been left outside. I also almost never use any of the tinder from my firestarting article, and my one extravagance is to use matches and sometimes a piece of paper or a napkin to get things going. To me, it isn’t valid to test any of these products under ideal conditions, but I always end up getting the stove going.
The other issue with the Rocket Stove is one of pure BTUs. Even gassifying the biomass, there is only so many BTUs in that material, and it takes some serious BTUs to boil water and cook your dinner. I have even successfully canned food with a canner using a couple small branches picked up off the ground in my Rocket Stove, but it was not easy. When I get done with one of these articles I stink like a chimney for three days, because I have to repeatedly blow on the embers to get fresh fuel into a “raging fire” quickly.
The Biolite stove solves both the lighting problem and the BTU problem with a built in electric blower fan. It’s TEG generator charges an internal battery pack built into the stove. This makes for easy lighting, because the blower “fans” the flames and gets even wet fuel going instantly with a little bit of burning tinder. For BTUs, I was able to boil the water in the pictures here in less than two minutes, for what would otherwise take 20-30 minutes.
Also, within about 3 minutes, my phone started charging via the 5 volt plug on the front of the stove. The Biolite supposedly charges at two watts on low, and up to 4 watts on high. I didn’t use the high, but even at low I didn’t get the “You Should Use the Charger that Came With Your Phone” message from Android. A regular wallwart charger is around 1 amp for phone sized, which is 5 watts at 5 volts. There is no question that you could use this to turn your phone on periodically to get a beaaring, check the topo in front of you, and even make a radio contact.
The Biolite does burn fuel really fast. I have some branches that are about an inch and a half thick that I have used for several of these articles, and with the regular Rocket Stove I usually split them with a hatchet so that they burn faster. With the Biolite, the thickness was a plus, because air is being injected into the chamber, allowing the wood to burn much faster with much less surface area. The “logs” the length of the stove were gone in 10 minutes, but in that time I had already cooked my beans and charged my phone a couple percent. If you are in an area with a lot of fuel on the ground, don’t even think twice about this stove being a worthy investment. For burning available ground fuel that has a high percentage of moisture, you can’t do better.
The Power Practical Powerpot
But what if you live in the city? Or even suburbia? With nicely trimmed trees around as your exclusive source of fuel, you aren’t going to get a lot of cooking done without a lot of walking. Gasoline, however, will be in plentiful supply. All of your neighbors who ignored your urging to prepare for what is coming will be dead, and their cars will either be sitting in front of their house or stuck on the road. If you have a siphon (search Amazon/Ebay for “liquid transfer pump”) and a gasoline stove, you’ll have all the cooking fuel you need for years, in sealed containers just waiting for you to take it. Gasoline, and “dual fuel” stoves can be found on Ebay for under $50, and I actually saw a single burning Colelman at Walmart the other day for like $65 as well.
I hope to get to a fuel comparisons article at some point, but I can tell you that I learned a ton from Steven Harris’s fuels video, for which he gets $14.95 on his website. When it comes to BTUs you can store, there is not even a close comparison to regular old Gasoline, and with Pri fuel additive, it lasts almost indefinitely. Search Ebay for “gasoline stove” or “dual fuel stove” and you’ll find single burners for under $50 and doubles for under $100, sometimes much less used.
There are two sizes of PowerPot, 5 watt and 10 watt. But beware, these are not for use with a Rocket Stove in my experience. There just isn’t enough BTUs, becuase you are using water as a heat sink and there is no metal even close to water in the efficiency of heat transference. Technically could you use these pots with a Rocket Stove dry? I don’ know and I haven’t tried it, but as instructed, I would stick to gasoline stoves with the PowerPot. See the pictures for more.
The Devil Watt TEG
If you plan to stay in one location and that location has plenty of fuel, there is really no comparison in a consumer TEG product to the Devil Watt line from Tegmart. The device I tested is their smallest, a 15 watt, and I tested the open flame version. With a Rocket Stove I knew that I was not going to get more than a few watts, and in my tests I was able to get a steady .3 amps (at 12v), which is about 4 watts. As you can see from the pictures, I hooked the Devil Watt up to a solar charge controller to see how much throughput I was actually getting.
The open flame version uses 4 TEG pads mounted between two huge aluminum heatsinks. The top heatsink, on the “cold” side of the pad, has a fan that blows cool air down onto the heatsink, and the electronics to convert the small voltage from the TEG pads into the 12 volts that are supplied from the charging cord. The bottom heatsink is in direct contact with the flame, and since the pads can take temps up to 842 degrees, you can actually use this device with a gasoline or propane flame.
The Rocket Stove doesn’t have to worry about heating it up too much, even with a raging fire in the chamber, so as you can see from the pictures, I used available material on the ground to seal the sides up some to prevent hot air from escaping the fins of the heat sink. It may look silly, and I have no idea if those little yellow fruits are edible, but they made a big difference in how much wattage I could get from the Devil Watt.
Most of the Tegmart products are made for woodstoves, and they did send me the 15 watt woodstove version which I will test when I get to that cookstove that I turned you guys onto several months ago. It will be cool to see if I can get the 15 watts from it while cooking, canning, or whatever. The power chart that comes with the Devil Watt shows that this model peaks out at about 13.5 watts at 725 degrees, with a heat source 100 degrees hotter.
From there you can go up to 100 watts with the Devil Watt products. The 10 watt is currently $234 on the Tegmart website, and for a Rocket Stove you don’t need more than that. I haven’t seen the Devil Watt products any cheaper through their Ebay store or other places online FYI. They are a small company and the best you’ll do is to buy them direct. The 100 watt is currently $725, which is a great buy if you heat with wood anyway. It could also be used with that Military H-45 gasoline/diesel urban survival stove that I reviewed before last winter as well. Both that stove and almost any woodstove produce way more heat than you need to survive, and these thermoelectric heatsinks allow you to save that energy for use on other things like lighting and communications.
Note that Tegmart also has a lantern coming out in October. I wanted to get this article out as quickly as possible, because their products are just that good. Both of these 15 watt generators came with two fully fireproofed charging cords, one with both a 12v and 5v jack, and one to hook directly to a battery or charge controller. All of the components on the Tegmart products are heavy and rugged. If you are serious about TEG power, I don’t think you need to look any further.