Every day over half the earth's population use a stove that burns some sort of biomass. Wood, dung, peat, or some sort of natural material feeds the world.
In a real sense, burning biomass is just solar power, collected by plants and turned into fuel. Sometimes the solar energy passes through an animal and is dried and burned after said animal extracts even more nutrients. Technically, fossil fuels are biomass; coal is just compressed plants from 350 million years ago. We, however, are concerning ourselves here with fuel created more recently -- fuel that is replaced by new growth, continuing the cycle of converting solar energy to wood to campfire.
In recent years, biomass camp stoves have become more popular as we have become more aware of our carbon footprint. While it's true that the amount of fossil fuel burned in your stove in a week is a pittance compared to driving to the grocery store, biomass stoves have other benefits to be considered. For the most part, biomass fuel is free or nearly so. The most common fuels, such as twigs and pinecones, are omnipresent. Dung is abundant, especially in rural areas. Charcoal is free if you find an old campfire ring where the fire was put out before the charcoal was consumed, and very cheap if you buy it. A bag of Kingsford will fuel your stove for a decade. Other fuels made from biomass, such as ethanol and methanol, while not free, still have the benefit of a cleaner burn, and they can be extinguished with water.
As a paddler though, one of the things I like most about biomass stoves most is that they are almost silent. Cooking on a sandbar when owls are calling back and forth across the river is a lovely thing -- if you can hear the owls over the roar of a stove.
But how to test...
It's easy to test gas stoves (Check out our recent review of 8 Classic Campstoves) since the fuel is constant in its composition. A pound of white gas has about 11,000 BTUs in it, period. Twigs are species-dependent, plus there are other variables such as moisture content to be considered.
To remove as many random variables as I could, I standardized the fuel, and controlled moisture content. For the wood-burning test, each stove was fired with:
• Six 3-inch pieces of 5/16-inch doweling.
• Three 3-inch pieces of 3/4-inch x 3/4-inch pine trim.
• 2 tsp of methanol to get the whole thing started.
For the methanol test (when applicable), the cup was half-filled with 95% methanol (laboratory grade stuff).
For tablets, I used one Esbit tablet, broken in two pieces.
The times listed are from touching the match to the fuel to rolling boil. The wind was 5-10 mph when I was testing wood; the methanol and fuel tablets were tested inside.
Click the links below to read about each stove:
Fueled by twigs, grasses, and driftwood, the Kelly Kettle made something out of nothing.
It weighs nothing and works great. You won't find a lighter, more compact stove.
The BioLite CampStove is a high-tech biofuel burner that performs beautifully
Handmade in the USA, the Bushcooker is a simple and brilliant biofuel stove.
Conclusions: All these stoves have their places. If you don't care about weight and like a clean burn, the BioLite is great. If you want ultralight, the Emberlit is your stove. If you just need hot water, the Kelly Kettle is a great choice. If you want simple and effective across the board, the Bushcooker is fantastic.
Fuel-choice Sidenote: Leave No Trace vs. Leave Less Trace
There is a serious discussion to be had about no trace vs. displaced trace. Stoves run on petroleum leave a trace, it just happens to be on an oil field somewhere far from your pristine campsite. Burning wood can be better in many situations, but here is always a risk of forest fire, and well-traveled paths quickly become fuel deserts.
Like many debates about false dichotomies, it's fruitless. The gas you burn in your camp stove pales in comparison to the gas in your tank that took you to the trailhead or put-in.
Like some vegans, people who use biofuels are primed for a greener-than-thou affectation. Yes, you have made a choice, and that's great; more power to you, but using a biofuel stove doesn't make you superior. Each fuel has its appropriate place, so use best LNT practices and minimize your impact. Just be thoughtful about your choices.