[ghostbust555]

How are you saying this is carbon negative? Don't get me wrong the process is impressive and very cool, but the marketing around it just feels scammy.

-5kg of carbon per m2? How? The lignin based binder absorbs more carbon from the air after it is placed into the road? I may be misreading but it seems like these numbers are based on the amount of carbon in the lignin itself (i.e. since it isn't burned which would be positive, you can count it as negative as it is not burned)

If I am wrong on this, please correct me. But it sure sounds like a lot of conveniently vague statements to make for nice sounding numbers. This would be a shame as even without misleading claims of CO2 reduction, the benefit of removing oil from the process and replacing it with a renewable source is clear and should stand for itself.

If the binder does indeed absorb C02 over time what is the rate? What effect does it have on the binders stability? Or if its used in its manufacturing how are you sourcing the CO2? What is the breakdown timeframe for the binder releasing any sequestered carbon back into the atmosphere?

[snewman]

OP says the lignin is "a waste product from the paper industry" and "majority of lignin is burnt". So it sounds like: currently, grow tree (pulling carbon from the atmosphere), process for paper industry, burn the resulting lignin, carbon returns to atmosphere. With this process: grow tree, process for paper industry, embed lignin in road material. If the lignin remains in the road more-or-less permanently (I asked about this in a separate comment), that sounds like legit removal; the carbon started out in the air and ends up in the road.

[haakonzen]

Yes exactly, that's how we think about it. We are using nature's own capture machine, trees... thanks for this clear explanation :)

[shafyy]

I agree. Stop using empty marketing words like "carbon negative". Your product seems good enough that you don't need to resort to this.

I'm sure there's a definition out there of carbon negative that means what you say it means, but if we're being honest carbon negative means that doing more of something reduces the amount of carbon in the atmosphere. You can't claim that not burning lignin is carbon negative since this product already exists as a byproduct in the paper industry (as you said). By repairing roads you're still emitting more carbon than removing from the atmosphere.

[libertine]

I don't agree with you.

If the product of the whole operation ends up with less carbon in the atmosphere, then it is in fact removing carbon. Plus they aren't using binders that contribute to more carbon to the atmosphere.

Now, we can be extremely strict in this definition and unless a company actually produces 0 carbon and is still extracting it from the atmosphere would be the ones who could claim they are "carbon negative", but then I guess not even CO2 extractors could claim that because they still need to be built and consume power.

I don't think that will get us anywhere. By that logic not even trees are "carbon negative".

In the end it's a matter of perspective, because what we're actually doing most of the time is offsetting/moving carbon around, and there's nothing wrong with that.

If it's captured from the air by a chemical process, or stored underground, or if it simply is stored in a byproduct that's reused and never reaches the atmosphere, it's all the same.

[throwawaylinux]

> -5kg of carbon per m2? How? The lignin based binder absorbs more carbon from the air after it is placed into the road? I may be misreading but it seems like these numbers are based on the amount of carbon in the lignin itself (i.e. since it isn't burned which would be positive, you can count it as negative as it is not burned)

Replace the lignin with some fantastical material that contains no carbon and requires no carbon to produce, and after it is laid on the road it quickly absorbs CO2 from the atmosphere equivalent to the amount of carbon that lignin contains.

Would you say that is carbon negative?

[hinkley]

Nope.

Nor is buying a bunch of stuff at the store that you don’t need just because it’s 35% off retail price “saving money”.

Cash flow positive is not losing money slower, it’s making more than you spend. Carbon negative absorbs more carbon than you spend. Including in chopping up an old road and recycling it, which is going to take a lot of power.

If I had a box that you plugged in that was actually carbon negative and I forgot I left it running while I was on vacation, I would not feel guilty. If doing nothing results in less carbon emissions than doing something, it’s not negative.

[hinkley]

> -5kg of carbon per m2

That machine that chews up the road and lays it back down, how many kg of carbon per m2 does it burn?

I think too you have to compare the lifetime pollution of a bitumen patch versus the point source pollution of grinding a road up in the open air and putting it back down. There's going to be a ratio of resurface vs patch that has a lower cost than using either strategy exclusively. Especially if you use their chemistry for patches, instead of resurfacing.

[lvs]

This was my first reaction as well. I think the subtext is that the byproduct is currently being burned as a fuel source, which is common for things like sawdust in mills. So there's one aspect of this calculation that could be waaay off. If the mills that would have burned this byproduct in a boiler are selling it instead, they'll need another energy source for their boilers! If that energy source is a fossil fuel instead of a wood byproduct, then this "upcycling" has inadvertently become carbon positive (or perhaps neutral at best). And it will be a lot easier to retrofit an industrial boiler for natural gas than to convert it to electric. Even if it were electric, most of the world does not remotely have as clean a grid as Norway's. So it would be some decades before any carbon advantage emerges.

[hansarne]

Thanks for the comment. See calculation breakdown added in a few threads above. Some of our thoughts about the carbon negative part:

Paper mills captures CO2 from trees (that are sustainably harvested, more trees planted than harvested p.a.) of which parts of it is released after some of the lignin is burned (inefficiently) for fuel. If they stop burning lignin for fuel, they need other energy sources, and then the question is how the paper mill chooses to do this: - The mills can choose to burn fossil fuels, get a renewable source, or buy electricity from the grid. We will only source lignin from players serious about sustainability and green alternatives (industrial broilers could also use green hydrogen), alongside prioritising maximised energy efficient operations - Even if they get electricity from the grid, the world is moving forward and we’re luckily reaching a point where additional capacity in the grid is coming from renewables, while fossil is decreasing - boosting new renewable buildout more

What’s very important in what you point out is that when we expand our lignin supplier base, we need to be careful in selecting our suppliers, understanding their alternatives and understanding our Scope 3 emission effects to ensure it aligns with our mission of saving the planet :) And that's what we will do - ensure that this ends up on the right side.

[hinkley]

Taken to the other extreme, as the value of sawdust goes up the incentive to reduce sawdust goes down, decreasing the number of board feet per tree, increasing trees cut for lumber.

If you find a better use for sawdust, great. But if you could invent a new saw blade with a smaller kerf, you’d be helping more.

[AtlasBarfed]

"Even if it were electric, most of the world does not remotely have as clean a grid as Norway's. So it would be some decades before any carbon advantage emerges."

So.... you give up? This is stupid all-or-nothing absolutist thinking. I'm not saying OP YC is the greatest thing since sliced bread, but long-term sequestration of tree carbon is a carbon sink.

Solar/Wind is at LCOE parity with natural gas turbine. It will pass it soon, with basic subsidies (as if fossil fuels aren't subsidized) then storage won't be a disadvantage either. If not, emerging economies of scale and tech progress in wind/solar will leave natural gas in the dust.

So even if the grid is dirty now, there is a clear path forward, and the grid will adapt to the changing pattern, and we already have the delivery method solved (the grid). And there are opportunities to possibly scrub carbon from central generation. Not as much as the sociopathic petroleum companies would like you to think so they can go business as usual, but better than an ICE car.