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Comment by imeron | Hacker News Reader

In my country they consider heating with wood "renewable energy". This is essentially cheating on the subject.

It's not cheating, it's conflating renewability with pollution generation.

Forestry is a well-understood topic that has made wood one of the most widely-used renewable resources in the world. Burning wood still produces large amounts of carbon dioxide/monoxide.

The wood has absorbed the equal amount of carbon from the air, which has reverted the previous burning. As long as we won't take down all the trees, it shouldn't be accounted as net negative.

Of course the other pollutants created from burning wood in population centers kill us when inhaled, so we've traded a minor source of CO2, which might kill us through some correlated highly delayed uncertain mechanism in an uncertain future, for something that is actively toxic and cancerous.

Burning wood for heating is the diesel car story all over again. The tradeoff makes zero sense.

Burning anything can be "actively" toxic and cancerous. You can argue about the process of anything, but that shifts the conversation away from the energy source.

Wood doesen't have to be burned in X place, and it _could_ be gathered and processed using clean procedures, but they're outside of the scope of wood being carbon neutral.

The fossil fuels burned during the planting, harvesting and transport of the wood also needs to be taken account.

In that case, unless the entire chain uses renewable energy, it can't be considered carbon neutral.

I wouldn't shift the burden of the entire chain to wood alone. The tools are not wood-exclusive, and should be considered on their own.

If you plant a tree, let it grow and then burn it the whole process is carbon neutral, the tree captured the carbon from the air to grow.

If you burn existing forest and do not replant it it does produce extra CO2.

Plants capture CO2, but not CO. Wood burning produces both CO2 and CO (with the balance between the two depending on how well ventilated the burner is), so the whole process still ends up producing pollution.

Also, even if the process as a whole is a net neutral over time, the system requires some amount of CO2 buffering in the atmosphere. The more you use wood as a fuel, the more CO2 you'll have in the atmosphere as part of this buffering.

Or, put differently — "net neutral" just tells you that you can reach a steady state, but doesn't tell you how heavily polluted that steady state is. Higher numbers of wood burners in use still translates into a more heavily polluted steady state.

Wood from managed forests is renewable energy, and arguably carbon neutral as well.

It's renewable, but where does that burnt carbon go?

It goes back to where the tree extracted it from: atmosphere.

That's why it is usually considered carbon neutral.

True - but the management, production and transport of the wood pellets that go on to be burnt, produces more co2.

Plus burning stuff isn't that great a way to make power, especially wood - if you have ever tried to heat a house with wood verses a coal fire you'll understand.

Right now the wood pellets are just a way to skirt the rules - I doubt they'll be part of the mix for long, as solar/wind drops in price, along with cheap and reliable storage.

It's absorbed by new trees, planted to replace the ones cut down.

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