[anamax]

You're switching contexts.

When you switched from burning lignin to solar, you reduced your carbon usage.

However, what happened to the lignin that you stopped using?

If it was burned somewhere else, the total carbon usage remained the same even though you changed your usage.

If it was stockpiled and is now decomposing over three years, the carbon usage was time-shifted and will be back where it was in three years. (However, total carbon usage will be reduced the first and second year.)

This is supposedly a usage of lignin that results in no release, so it actually is carbon-negative (assuming that the processing doesn't use more carbon), regardless of what other folks think that they did. That said, it's probably actually just time-shifted, albeit on a long time-scale.

Note that both coal and diamonds are actually time-shifted carbon usage, on the scale of millions of years.

[tomsyouruncle]

> When you switched from burning lignin to solar, you reduced your carbon usage. However, what happened to the lignin that you stopped using?

In my scenario, CarbonCruncher bought the lignin I stopped using and made a road out of it. Crucially, in doing so they claim to have a negative carbon impact because they'd trapped that carbon in the ground. But I already claimed that impact when I stopped buying and burning it myself and switched to a zero-emission energy source.

So my (genuine) question remains: we can't _both_ claim the benefit, so who's right?

[anamax]

What's the relevance of "claim"?

Thousands of people get "best grandma" coffee mugs each year. Logically, only one of them actually is, but who cares and why?

[ghostbust555]

This is exactly my point (the after 3 years if it decomposed you are just time shifting) which is why I asked how long the roads take to decompose and what they translate into. Sooner or later that lignon in the road will become C02. But is that in 10 years? 100? If its time shifting it only by 15 years or so then its NOT reducing the total carbon to the atmosphere, just temporarily storing it. No different than putting the lignin in a warehouse for 15 years before burning it. So to call that carbon negative is just... bad math at best.