Composting is often framed as a gardening hobby, but it is also a climate action. The reason comes down to what happens when food waste ends up in a landfill instead of a compost pile.
The distinction matters, but it is easy to oversimplify. Composting still takes energy to collect and process food, and a poorly managed pile can emit methane. Its climate value depends on what would otherwise have happened to that food, how the compost is made, and where it is used.
Why landfilled food is a problem
When food breaks down in a landfill, it is buried without oxygen, and that anaerobic environment produces methane. According to the EPA, municipal solid waste landfills are one of the largest sources of human-related methane emissions in the United States. Methane is a short-lived but powerful greenhouse gas, with far more warming potential than carbon dioxide over the near term.
Food decomposes quickly compared with many other buried materials. In a 2023 EPA analysis of U.S. landfills, landfilled food was responsible for an estimated 58 percent of methane emissions that escaped from municipal solid waste landfills in 2020. That figure describes a national estimate for one year, not the emissions from a particular household bucket.
How composting changes the outcome
Managed composting supplies oxygen as microorganisms break down organic matter. Keeping the material aerated can avoid much of the methane associated with burying it in a landfill. Compost applied to soil also returns organic matter and may reduce other inputs, depending on the site. The EPA’s sustainable management of food resources put prevention first and recognize composting as a way to manage scraps that cannot be eaten.
Oxygen is not guaranteed just because a pile is called compost. A waterlogged, compacted heap develops low-oxygen pockets. Operators manage moisture, ingredients, and airflow partly for this reason. A home composter can do the same by mixing wet scraps with dry leaves, covering fresh food, and turning a compacted pile. Our troubleshooting guide explains what odor and moisture reveal about a stalled pile.
Preventing waste comes first
Composting is important, but it is not the first choice for edible food. The EPA’s Wasted Food Scale prioritizes preventing surplus food, donating suitable food, and using food for people before recycling the unavoidable remainder. That order matters because growing, cooling, transporting, and cooking food already used land, water, energy, and labor. Composting recovers value from scraps; prevention preserves the value of the food itself.
For example, preventing a loaf of bread from going stale avoids the impacts of producing, packaging, shipping, and disposing of it. Composting that same loaf can recover some value at the end, but it cannot undo the earlier losses. That is why the EPA Wasted Food Scale orders options by more than how much material they keep out of a landfill.
Compost can help soil handle a changing climate
Mature compost adds organic matter that can improve soil structure and water retention. Healthier soil can absorb rainfall more effectively and may need less irrigation during dry periods. Results vary by soil, climate, and application, so compost is not a single solution to climate change. It is one useful part of a broader system that includes wasting less food and keeping organics out of landfills.
It is also important not to count every ounce of compost carbon as permanent storage. Some breaks down after application, and the result varies with the soil and the way compost is used. The strongest claim is practical: mature compost can help build soil structure and hold water, while diverting unavoidable scraps from disposal. Our soil health guide looks at those benefits and their limits in detail.
What about anaerobic digestion?
Some food scraps are processed in sealed digesters rather than open composting systems. Microorganisms break the material down without oxygen, but unlike a landfill, the facility is designed to capture the biogas. That gas can be used for energy, while the remaining material can be managed for beneficial use. The EPA recognizes both composting and anaerobic digestion as pathways for recycling food scraps when prevention and donation are no longer possible.
Digesters make the most sense when they capture and use biogas and manage the remaining digestate well. Compost facilities must control air and moisture. Both need clean incoming material, transport, and operating capacity. Neither is automatically superior in every location. The EPA’s Field to Bin assessment compares these routes across several environmental measures, rather than giving a universal answer based on one number.
Why household participation still matters
One banana peel is not a climate strategy. A reliable habit shared by hundreds of households is different. It gives collection programs a predictable stream of material, helps communities learn what infrastructure they need, and makes food-waste diversion normal. The point is not individual perfection. It is steady participation in a system that can scale.
Clean sorting is part of that habit. A plastic fork in a food-scrap bucket does not help the climate case for collection. Ask your local program what it takes and how the scraps are processed. If you compost at home, use the finished material where plants and soil can benefit from it.
The local picture
Food waste is a big share of what we throw away, so diverting it adds up quickly across a community. That is the whole idea behind Torus. You can read more about the problem we are solving and see our measured impact on the about page.
Turn your scraps into impact
Start with one change that prevents edible food waste, then separate the scraps that remain. If you are in our New Jersey service area, sign up for free food-scrap pickup and check what we accept.
