[arnorhs]

Does orange peel not produce any CO2 / methane when left like this? I'm assuming there is some negative carbon footprint before this becomes a positive?

The ecological win definitely looks nice on paper, but whenever people talk about compost the carbon footprint / gas emissions is always at the front of people's minds, and I don't really see that discussed in the article.

The article does say

> Especially since, in addition to the double-win of dealing with waste and revitalising barren landscapes, richer woodlands also sequester greater amounts of carbon from the atmosphere – meaning little plots of regenerated land like this could ultimately help save the planet.

How long will it take for it to cross the CO2-neutral mark? Maybe a silly question, definitely not my area of expertese.

[sfink]

CO2 is going to be neutral for the peels. You're just transporting it from where the oranges grew to where they were dumped. The CO2 benefit is purely from the trees and other biomass that grow where they wouldn't be growing before.

As for methane, that's a good question. Orange peels are better than most things because the limonene inhibits methane producing bacteria. But you'd still get quite a bit in the deeper piles (that produce the anaerobic conditions needed for methane production).

Spreading them out more would help, but might interfere with the beneficial effects.

[rustystump]

I may be wrong but isnt most of the tree carbon capture over stated as in the overwhelming majority comes from algae in the oceans?

While forests are great they are not the best focus iirc compared to the oceans.

[nomel]

Yes. A potential method of capture is to seed the ocean with more iron [1], to help the algae.

I assume that China will be the first to do these sorts of things, since the west will be too hogtied in regulations, lawsuits, and bureaucracy.

[1] https://www.hawaii.edu/news/2026/02/17/ocean-iron-fertilizat...

[subscribed]

China could definitely do this, to offset the minuscule of the destruction they do with the dark fishing fleets around (and possibly in) protected marine areas.

[subscribed]

In retrospect that was a rather stupid comment.

It's not like "the global north"/"the West" wasn't guilty of the enormous ecological damage _everywhere_ already.

[laurencerowe]

The orange peel is going to decompose and produce CO2 either way. Methane is produced when there is not enough oxygen available while decomposing, which certainly seems a possibility if it's dumped in big piles.

[PaulHoule]

Mostly.

Remember the orange trees took the CO2 out of the atmosphere to make the peels. Some of it, probably most of it, is going back into the atmosphere but some of it is going to become soil carbon which could be retained for decades

https://en.wikipedia.org/wiki/Soil_carbon

Soil carbon is like dark matter in that there is a lot of it and it is poorly understood.

[dgacmu]

You're getting downvoted but it's a reasonable question if posed in good faith. The tl;dr is that there are really a few options for what could happen to those orange peels:

(1) Landfill burial

   (1a) Without methane capture and use: Produces methane, relatively high short term warming potential.
   (1b) With methane capture and use: Ends up as CO2 after burning the methane.

(2) Composting (this approach)

   (2a) Mostly aerobic: Produces CO2
   (2b) Mostly anaerobic: Produces methane

A deep pile that is never turned will decompose anaerobically, resulting in fairly undesirable methane. A shallower pile or one that is mixed well will result in mostly aerobic decomposition. The aerobic decomposition will produce CO2 but not huge amounts of it. Each hectare of land could absorb something like ~8 tons of CO2 per year; with 7 hectares, the CO2 emitted by composting 12t of oranges is going to be dwarfed by the new vegetation. After a few years when you're growing big trees, the rate of CO2 absorption might rise as high as 20-30t/year/hectare in costa rica's environment. And this is probably an underestimate, as the soil amendment of the orange peels seems to have stimulated faster regrowth than would have happened otherwise.

And perhaps more to the point: There isn't really a purely "no co2" way of disposing of organic matter other than perhaps burying it at the bottom of a deep mineshaft (but the co2 or methane will be produced anyway). Landfilling it is strictly worse - you still get the decomposition products, _or worse_ because you'll mostly get methane, but without producing useful soil byproducts.

Overall this project is a huge win on a carbon perspective and a waste reduction perspective.

[mvdtnz]

It's not a reasonable question. What's the alternative for the orange peels? They were going to rot and release that CO2 whether they did it in a big pile here or somewhere else.

[dgacmu]

That's why I said if asked in good faith. :-)

But seriously GP could have had a mental model that landfilled orange peels might sit there for a long time -- which depending on conditions and food could be true on human scales (like 10-40 years) but not on the scale of 100 years. Especially if the conditions were dry -- a dry orange peel is pretty robust. That's not likely to be the case in Costa Rica, but I'll forgive some naivety here absent demonstrated malice.

[dgacmu]

*naivete

that word and I have never gotten along well. insert obligatory joke at my expense.

[bcjdjsndon]

The fuh? Oranges a climate risk? You've gone full 360 crazy there