A first-person experiment from the Repricing Carbon project. New here? Start with What Is a Carbon Credit?
For months I have written about carbon credits from the outside, reading methodologies and explaining them in plain English. At some point the obvious thought arrived. If I really want to understand a carbon credit, I should try to make one. So I am building a worm farm.
This is not a metaphor. I mean actual worms, eating actual food scraps, in actual bins in my care. I have been an organic farmer and a permaculture designer for years, so the worms are familiar ground. The carbon credit is the new part. And the moment you try to turn a pile of compost into a credible climate claim, every abstract idea in this series suddenly gets very real.
Why worms have a climate angle at all
Vermicomposting is just composting with worms. They eat organic waste and turn it into rich, stable soil. The climate angle comes from two places. First, food scraps that rot in a landfill release methane, a powerful greenhouse gas. Divert them to a worm bin and you avoid those emissions. Second, the finished compost helps build carbon into soil, where it can stay.
Avoiding methane and building soil carbon. One credit is supposed to represent one ton of carbon dioxide avoided or removed. So in principle, worms doing this at scale are doing exactly the kind of work a credit pays for.
In principle is the phrase doing a lot of work in that sentence. Here is where the experiment gets humbling.
I put my own worm farm through the five questions
Earlier in this series I wrote about the five questions that decide whether a credit is high quality. It is one thing to explain them. It is another to point them at your own bins and watch yourself squirm.
That last one is the gut punch. I can feel, in my hands, that I am doing something good. But a carbon credit is not built on feelings. It is built on evidence that a stranger can check. My backyard bins do not produce that evidence, and pretending they do would be exactly the kind of weak credit this whole series warns buyers about.
What the experiment actually taught me
Here is the honest result. A single backyard worm farm will not mint a real, tradeable carbon credit. The benefit is genuine but small, hard to measure, and probably not additional. To produce a credit anyone should buy, you would need scale, rigorous measurement, a sound methodology, and independent verification. The very things that make good credits expensive and rare.
And that is the lesson I could not have learned from reading. I now understand, from the dirt up, why the market is so demanding about quality. The gap between “I am clearly helping” and “here is a credit you can defend in a boardroom” is enormous. Every honest person in this market is standing in that gap, trying to close it with evidence.
So why keep going?
Because the dream is bigger than one bin. Scaled up, with community food waste flowing in and real measurement in place, vermicomposting can become a legitimate climate project. People are building exactly these projects now. My little experiment is me earning the right to talk about them honestly, by trying to do the thing myself and respecting how hard it really is.
I will keep the worms fed and keep you posted. If nothing else, I have a deep new respect for everyone trying to turn real, messy, on-the-ground good into something a market can trust.
Where to go next
If you want to see how small good projects can grow into credible ones across a whole market, read the reform loop. And if my worm farm got you curious about the bigger idea behind it, I wrote about that too: why the carbon market needs people who have actually worked the land.
A note from the author. I have spent the better part of two decades working in sustainability: in solar and clean energy, in permaculture and regenerative land projects, and in marketing the mission-driven businesses trying to do this right. Carbon credits are the part of that world I came to most recently, and I am still very much a learner here. There are people who know this market far better than I do, and I have real respect for the work they have put into building it. If I got something wrong in here, I apologize, and I would genuinely like to hear about it so I can learn and correct it. I am writing this to start a conversation, not to have the last word. That is the whole point. This is a learning experience for me too, and the conversation is what moves all of us forward. If this piece helped you, share it. If you see it differently, even better. Let’s talk.