BioLite has been developing solid-fueled stoves with an unusual thermoelectric technology for several years. The camp stove, which started shipping in June, creates the ideal conditions to burn any local biofuel, rather than having to carry in a petrochemical-based fuel. While not designed for mystical caves, the pastel beauty of deserts, or snow-bound wonderlands with no usable vegetation. it is a perfect companion for a hike in the woods.
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- Weight: 2lb 1oz.
- Fuel: solid biomass may be sourced locally but fire-starter sticks (provided) make a quick start.
- Heat shield and P & C module as handle makes it possible to move stove without being burned.
- A small percentage of the heat is used to power ventilate and swirl the combustion gases for a complete burn.
- A thermoelectric generator (TEG) produces electricity from the heat of the fire.
- A non-replaceable lithium-ion battery backs up the TEG.
- Pot weight limit: about 8 lbs. Pot must be removed to add more fuel.
- A USB port for power/charging devices.
- Cost: $129. USD direct, new orders, shipping by mid July.
Solid Fuel vs Liquid Fuel
For several decades, campers have been using petrochemical-fueled stoves. They pack in fuel containers and pack them out again. They are reasonably economical, and it takes almost no attention to light and maintain a fire for the needed meal.
In contrast, most of the YouTube reviewers of the BioLite stove seem so excited with the unusual device that they decided to skip reading the directions. Many of them also seemed somewhat unfamiliar with starting and operating a solid fuel (wood) fire.
In fairness, the device is an intriguing blend of technologies and in about the same sized package as the petrochemical stoves. But it is not the same. Wood fires differ from liquid fuels. The moisture content of the wood has to be driven off by heat and this affects how the fire burns. Hardwood, the best choice, offers fewer sparks, with hotter fires that last longer. A liquid-fueled fire automatically mixes air and fuel. The size and shape and packing of the wood is important to getting a good mixture of air and solid fuel. Too little air or circulation will make the fire smoke, a sign of incomplete burning. The maximum size fuel for the BioLite stove seems to be about as thick as a pinky finger and as long as a dollar bill. The forced airflow of the BioLite stove makes the process of a wood fire hotter, much easier, and more efficient.
Reviewers have remarked that there is very little ash left in the unit or soot on the pots. Enough air can get into the unit to start a small fire easily protected from any wind, but the initial smoke is a sign of inefficient burning. The burner shape alone does not allow enough airflow. The fan is required. And the technological trick is that this electrically operated fan does not need batteries.
The Thermoelectric Generator
The TEG is in the power and control module. A probe inserted into the flame conducts heat to the unit, which by the magic of electronics becomes DC voltage. The science has been described by Seebeck, Peliter and Thompson, or called simply the thermoelectric effect. It is a direct (solid-state) conversion from heat to electricity.
This gives the unit power for the fan that makes the unit more efficient. A USB charging port is an added bonus. As reported in the following video, there are similar fan-powered biostoves on the market that require batteries, but here the TEG eliminates the batteries.
Eyes on the Fire
Sometimes we praise technology for the freedom it gives us (liquid-fueled stoves). Here, we have to love the experience of feeding the fire. The stove needs attention to balance the fan speed and the amount of fuel. Smoke and lack of fuel are signs that attention is required.
The challenge will be to start the stove and not have to remove the pot and add more fuel before the meal is finished cooking. For those raised on the “plug and play” simplicity of a liquid-fuel stove, the BioLite offers a test of proficiency that should become a point of pride.
But it is not a campfire. It is a stove. It is designed to concentrate a small amount of heat in a pot for the relatively short time it takes to cook dinner. For camping, this is sometimes reduced to the time it takes to boil water — about 5 minutes for 2 cups of water. The device brings amazing technology into the hands of people who truly appreciate what it can do and are likely to spend the $129 USD asking price.
Electricity for USB
USB charging in the wilds is an idea we will certainly see more and more frequently, but charging devices typically requires a bit longer than the time to cook a meal. In a pinch, the stove might be used to power an LED light, charge your GPS (charge time up to 4 hrs), charge your batteries (4 hrs), power a SteriPEN Freedom UV water purifier, charge your phone, etc.
But, for everyday use, the attention and time required makes this a fun stove but an inefficient generator. The USB port seems a trendy gimmick with the real prize being an efficient wood burner that does not need batteries. It is a nicely built, solid stove that doesn’t use petrochemicals. However, you still may not want to give up on the solar-charging backpack.
Note: The Company has not responded to requests for further information.
Photo Credit: BreathontheWind via Flickr, used with permission.