I'm from Northern Ontario, and I agree that wood smoke can be killer, especially below -30°C (-22°F) when the smoke stays near the ground. Oven stoves, according to the article, address this. The section "Complete combustion", is all about this issue:
> Wood can be burned without too much air pollution, but then the temperature has to be high enough: 1100 to 1200 degrees Celsius. In that case, 99 percent of the wood is converted to CO2 and water vapour, almost without smoke. A metal wood stove, however, only reaches a temperature of 650 to 700 degrees, with an incomplete wood combustion as a result.
Are these significantly different in mechanism from so-called "rocket mass stoves"? I remember reading about those a few years ago. Seems like they burn very "clean" and require relatively little fuel to heat a home.
Rocket stoves are efficient when they're small, you have to have a secondary gassification byproduct burn chamber. I can't remember what the whole heat system is called, but it involves a lot of cob and clay.
Biofuels like wood can be roughly carbon-neutral, since growing them absorbs atmospheric CO2, and burning them releases that same amount of carbon back into the atmosphere.
Though obviously this isn't the case if the wood comes from badly-managed forests that are not replanted. And there are other effects that can make wood fuel carbon-positive:
True, but it doesn't matter. After you burn the wood, you are adding carbon that doesn't need to be there. The physics don't distinguish between carbon that is produced by a short carbon cycle or a long one.
In the case of wood, the carbon is accessed from, and ultimately returned to, the active biosphere. It's not fossil fuel that's been sequestered for 100s of millions of years, but was itself captured largely within recent decades.
Contrasted with burning coal, oil, or gas, preferred.
(Woodfuel may still be burned unsustainably, that's a separate question.)
Noted FWIW in TFA:
[U]nlike gas and oil, wood is a renewable and CO2-neutral fuel (the CO2 that is produced by the burning of wood was taken out of the atmosphere by the tree during the years before). The problem is that wood stoves are not very efficient, and extremely polluting.
Whilst it is for burning fossile files, when you’re burning the wood that grew on your property over the past 20 years, the carbon cycle is much shorter. Especially if your property grows it all back, it’s a closed carbon loop.
> Wood can be burned without too much air pollution, but then the temperature has to be high enough: 1100 to 1200 degrees Celsius. In that case, 99 percent of the wood is converted to CO2 and water vapour, almost without smoke. A metal wood stove, however, only reaches a temperature of 650 to 700 degrees, with an incomplete wood combustion as a result.