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by ponector 944 days ago
Is it? Energy output is directly related to carbon content. More energy density from coal mean more co2.

But coal is much much worse due to toxic pm2.5

2 comments

> Energy output is directly related to carbon content. More energy density from coal mean more co2.

No. It means you need to burn a larger volume of wood to get the same amount of energy. And when you increase the volume, you increase the emissions. The first sentence of this quote may be true, if we are talking about absolute amounts, but then in the second sentence density is a ratio (energy to volume), which is why it’s not true.

I don’t know all that much about relative PM2.5 emissions, but a brief search shows a paper, which argues that PM2.5 emissions depend more on combustion conditions than fuel type[1].

[1]: <https://pubmed.ncbi.nlm.nih.gov/31340411/>

A ton of coal will create much more co2 than ton of wood, isn't it?

For the same amount of energy the result should be similar amount of co2.

Coal is worse for people because burning it creates many unhealthy chemical components. Sulfur, heavy metals, etc

> A ton of coal will create much more co2 than ton of wood, isn't it?

Yes. But that hardly matters.

> For the same amount of energy the result should be similar amount of co2.

No. Apparently, wood is estimated to emit 30% more CO2 than coal for the same amount of energy[1].

> Coal is worse for people because burning it creates many unhealthy chemical components. Sulfur, heavy metals, etc

Is it more than when you burn wood though? I’m not knowleadgable enough to answer this question. I found one link about it[2], but currently I don’t have time to read it. In any case, the fact that it produces more CO2 than coal is a good argument against wood in my eyes. My argument is against wood, not in favour of coal. Coal is just a benchmark to measure against.

[1]: <https://ecosystems.psu.edu/research/centers/private-forests/...>

[2]: <https://www.intechopen.com/chapters/18644>

And wood is even worse in that regard
That is not true. Check out chemical components of coal ash.

I live in the region where people use coal for private heating. It is much worse than wood.