How Waste = Food

Imagine if we could create a super-efficient world where there was no waste… Actually, there’s no need to imagine it: nature is already ahead of us on this one.

In nature, almost all “waste” from one organism can be used as “food” or fuel by another organism—a concept explored by William McDonough and Michael Braungart in their seminal book Cradle To Cradle.

For example: a fruit tree’s blossoms fall to the ground and decompose into food for other living things. Bacteria and fungi feed on the organic waste of both the trees and the animals that eat its fruit, depositing nutrients in the soil in a form ready for the tree to use for growth. And so one organism’s waste is food for another, and nutrients flow indefinitely in cycles of birth, death, decay and rebirth.

Humans—the only creatures on the planet that produce landfills—are not quite so efficient. According to the Environmental Protection Agency, the United States alone generates about 250 million tons of waste annually, with nearly 175 million of those tons being thrown into landfills. To make matters worse, the decomposition of waste in landfills releases large amounts of methane into the atmosphere, making landfills the most significant human–related source of methane in the United States.

Clearly, humans need to change their ways to avoid turning the earth into one massive landfill. Fortunately, a number of clean technology companies are taking innovative steps to address this problem by turning what seems to be waste into energy, fuel, or other useful materials.

For example, California-based Enventix is developing proprietary conversion systems for turning waste, biomass, and other low-grade feedstocks into ultra-clean energy. This technological breakthrough rids waste and biomass of impurities in an economical manner—helping municipalities generate renewable power that is free of harmful emissions at efficiencies that were previously unattainable.

Meanwhile, Washington-based General Biodiesel, Inc. has tackled the seemingly dirty job of collecting used cooking oil from hundreds of Seattle-area restaurants. But instead of burning or burying it, the company recycles the grease as biodiesel, the ultimate non-foreign fuel. Springboard Biodiesel, based in Chico, California, takes this idea “on the road” by providing smaller biorefinery machines that can process used cooking oil wherever it’s generated, whether it’s at a restaurant, a community co-op, or a university.

California-based Micromidas is tackling an even dirtier form of waste than used cooking oil: sewage sludge. The company has found a way to harness microbes to naturally transform the carbon and other nutrients in sewage into biodegradable plastics that are safe enough to be used as food packaging or as biomedical sutures.

Across the Atlantic, French company Pyrum Innovations is developing a tire-recycling machine that “deconstructs” used tires back into separate quantities of rubber, metal, and usable petrol. This invention provides a way to tackle the existing mountains of used tires that never degrade and thus pose a huge environmental problem. It also offers tire factories a way to more effectively handle new waste that they produce. Given that European tire plants generate 2,000 to 7,000 tons of production waste annually—and have to pay €200 to dispose of a single ton—Pyrum’s potential impact is sizable.

With each of these innovations, our wasteful ways can come a little bit closer to nature’s closed-loop system—one where “waste = food”.