Why is wood seen as a climate-neutral fuel, but coal and oil are not? All these fuels are based on composed organism that collected carbons over their lifetimes, that are now used as a fuel. The only difference is the cycle time.
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Trees can be replanted to collect the carbon back from the atmosphere, and burned again. The cycle is nearly carbon neutral.
Fossil fuels are obtained from carbon trapped millions of years ago, that cannot be collected again from the atmosphere without expending energy. The cycle is not neutral, since there’s no carbon being removed.
The cycle time is pretty important in this case. Coal and oil only form under very specific conditions and take millions of years. So when we’re talking about carbon emissions with 1-20 year windows it might as well be infinity.
Wood on the other hand can be replanted and harvested again in 5-10 years.
To make things clear, I am not a climate-change denier and I agree that we need to stop burning fuels as soon as possible to keep our planet habitable. It’s just that I wonder why wood should be a green energy, when it’s in principal more or less the same as using coal and oil.
I don’t know why you believe it to be a “climate-neutral fuel,” as I’ve never heard of that. Wood is, however, considered by some to be a form of “sustainable energy,” as wood can be replenished in a reasonable period of time (by planting/growing more trees), as opposed to fuels like coal and oil, which could potentially take millions of years to replenish themselves.
Wood stoves and fireplaces are significant polluters, they are strictly regulated by a new [law](https://montreal.ca/en/topics/solid-fuel-burning-stoves-and-fireplaces) since 2018 in Montreal.
You cut down a tree, burn it and replant another tree in its place. In ten years or so the carbon from the burning of the first tree is absorbed from the atmosphere by the second tree, so it all becomes carbon-neutral. Coal and oil, on the other hand, have been accumulating underground for millions of years. We have no practical way to pump carbon out of the atmosphere, convert it to coal or oil and put it underground.
I really hate the term climate-neutral, because whilst burning wood only releases as much carbon as the tree absorbed during its life, that is true for pretty much everything. As long as we exclude extraterrestrial ressource mining, nuclear fission and nuclear fusion, there will always be the same number of carbon atoms on our planet, therefore everything is carbon neutral.
The big difference is of course that even the oldest trees are “only” a few millenia old. Therefore all the wood in the world only contains the excess carbon of a few thousand years. But the plants that are the basis for oil, coal, and gas formed layers over millions of years, therefore containing the excess carbon of millions of years.
So it is a bit like how lighting a candle in your house won’t change the room temperature, but burning thousands of them simultaneously will. The problem isn’t that oil is somehow worse than wood (considering the impurities in wood and oil I’d even argue that oil is better), the problem is that we burn oil way faster than it grows. That being said, if we somehow replaced all our oil fueled technology with wood fueled tech, it wouldn’t change anything (at least regarding carbon neutrality)
Because you burn wood that would eventually rot in the bush releasing carbon anyway.
Yes coal is totally natural and carbon neutral on a milion year cycle, but if you leave it alone it won’t burn by itself and unbalance our atmosphere. On the other hand wood will rot and make carbon anyway. So burning it is almost neutral toward the climate we like to have.
Coal is friendly with a climate we don’t want to have. Unless you are a lizard, you don’t want that climate. We like this climate.
The only people who ‘see’ wood as climate-neutral are people who don’t know much about power generation.
In theory, the cycle time you’re talking about could be important. Burning coal/oil means you’re putting carbon that has been sequestered for millions of years back into the atmosphere and doing so on a much shorter time scale.
However, in practice, the cycle time is meaningless because the real issue is that burning wood is energy-negative on an industrial scale. That’s why we transitioned away from it in the first place – it just doesn’t generate enough energy to offset the energy it takes to harvest/transport/process it.
So when you burn wood, you’re not really getting energy from the wood. You’re getting energy from the coal/oil it took to put the wood into the furnace in the first place.
Ultimately this means you might as well skip dickering around with wood and just directly burn the coal/oil to power your civilization – it’s a lot more efficient.
There is CO2 in the atmosphere and that is necessary for life. However having too much is an issue.
There are 2 categories, based on where the CO2 comes from: Circular and non-circular CO2.
Burning wood produces circular CO2. It releases CO2 which it had previously been absorbed when that tree was growing. You can also grow a new tree that will absorb the same amount of CO2 just released. In the long run, the total amount of CO2 in the atmosphere doesn’t change by burning trees. This is climate neutral.
Burning coal is not climate neutral as it will release CO2 in the atmosphere that was previously safely stored in the earth, causing the total amount of CO2 to rise. Burning coal/oil/gas/… is therefore CO2 positive and increasing the total amount of CO2 in the atmosphere.
Planting additional trees will not help reducing that additional amount of CO2 in the atmosphere. (It is CO2 neutral and the CO2 will be released again when the tree dies.)
In order to offset non-neutral CO2 from coal/oil/gas, we need CO2 negative technology that will capture CO2 from the atmosphere and safely store it elsewhere.
Also: If you would like to temporarily offset the CO2 from Coal/Oil/Gas, you would need to plant trees in the entirety of Africa and half of Australia and if you do, you just have created a severe water shortage.
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