[andjd]

In their FAQ, they mention this statistic.

> Every ton of biomass contains roughly 1.65 tons CO₂.

On it's surface this is impossible. Does this refer to CO₂ equivalents like Methane? It seems that for carbon specifically, the process (pyrolysis, transportation, etc) emits more than one ton of carbon for every ton of oil sequestered.

[wongarsu]

Of course the statement is a bit inaccurate, it should probably say "burning 1 ton of biomass generates roughly 1.65 tons of CO₂"

Oxygen is a good bit heavier than carbon, to the point that about 80% of the mass of CO₂ is oxygen. Since burning fuel is generally about combining carbon and hydrogen in the fuel with atmospheric O₂, producing CO₂ and H₂O respectively, you can get numbers like these even before accounting for high-impact gases like methane.

Edit: and of course photosynthesis is essentially the same process in reverse, taking in CO₂ and energy, adding water for the hydrogen and removing some oxygen (that gets vented to the atmosphere) to get energy-rich biomass.

[hinkley]

Only 16% of the weight of CO2 is the carbon. Since we’re concerned with the greenhouse effect of the molecule, that makes a bit of sense. But it also inflates both the rate of production and the value of capture so it could just as easily have been the other way.

[certifiedloud]

Conservation of mass need not apply.

[carbadtraingood]

It's the same way that burning 1 kilogram of gasoline produces more than 1 kilogram of CO2. Oxygen from the atmosphere gets bound to the carbon.