California’s CR&R digester can process 334,000 tons of food and green waste yearly, yielding 4 million diesel-gallon equivalents of RNG and 250,000 tons of fertilizer

Somewhere in Riverside County, California, a plant the size of a small stadium is digesting your food waste and spewing out fuel. It could pass for an outlandish piece of experimental technology. Still, no, it’s really there, working, and may well be one of the most underrated climate stories in the United States. According to the U.S. Environmental Protection Agency’s description of renewable natural gas from biogas, anaerobic digestion, which is the decomposition of organic waste by microorganisms in an oxygen-free environment, is turning into one of the more effective technologies America can use to curb methane emissions while generating fuel.

And there’s a particularly spectacular case of anaerobic digestion taking place in one of the waste facilities located in the city of Perris, about an hour away from Los Angeles. CR&R Environmental probably isn’t the household name you’re familiar with. However, it's a Southern California waste-hauling company that has built, almost in secret, what has been called one of the largest food-and-green waste digesters in the country.

What's actually happening in Perris


The facility processes the yard and food wastes collected through curbside collection programs, those materials we typically discard without giving them a second thought. This is achieved through an "anaerobic digestion high solids" system. BioCycle's on-site reporting found that the facility was developed in four stages, with each stage able to process about 83,600 tons of organic materials per year for a total capacity of over 330,000 tons per year upon completion. This is not backyard composting we're talking about here.

Trash in, truck fuel out

Here's the part that actually matters for your commute and your grocery bill, even if you've never set foot in California. The organic waste gets broken down by microbes into biogas, which is then refined into renewable natural gas, or RNG. Energy Vision's case study on the project puts the fully built-out facility is designed to convert its waste stream into enough RNG to displace about 4 million gallons of diesel fuel a year, while also producing roughly 260,000 tons of nutrient-rich fertilizer as a byproduct.

That fuel isn't hypothetical; it's already running CR&R's own fleet of garbage and recycling trucks, some of which are fed through a dedicated pipeline connection to the regional gas utility. Why does any of this matter beyond the smell test? Food waste in landfills doesn't just sit there quietly. As it rots without oxygen, it releases methane, a greenhouse gas that's dramatically more potent than carbon dioxide over the short term. Capturing that gas before it escapes and turning it into usable fuel is, functionally, a two-for-one: less methane in the atmosphere, less diesel burned on the roads.

The catch you may not know about

The EPA's biogas report puts a number on how far behind most of the country still is: about 94 percent of the food waste that is discarded across America is still getting landfilled and combusted rather than digested. Perris may well be an exceptional case, but then again, it is just an exception, not the norm. Building such projects is costly, and pipeline interconnections would cost millions of dollars. That said, Perris isn't entirely alone. South San Francisco's Blue Line Transfer facility runs a smaller food-and-green-waste digester that fuels its own collection trucks, and New York City's Newtown Creek plant co-digests food scraps alongside wastewater sludge to produce biogas. But facilities like these remain rare: most U.S. cities still lack this kind of infrastructure, and scaling it up to Perris's size is a different order of investment.

Why this should matter

Not living in California does not negate the relevance of the situation. Wasted food is one of the only environmental issues for which every person in the world is responsible for contributing to multiple times a day. Leftovers which are wasted before being consumed, spoiled spinach in the bottom drawer of the refrigerator, and additional french fries which were not eaten are all contributing to a tremendous greenhouse gas problem in a very visible way.

The City of Perris demonstrates what is technologically feasible once a city sorts through its waste instead of taking it to a landfill. Of course, this is not a cure-all solution to the problem. What really needs to be considered is whether or not American cities will fund the necessary infrastructure for such a plant to be created.