Millions of tons of coffee grounds are thrown away every year; estimates put it between and 8 and 60 million tons annually. Most of that ends up in landfills. And because of its abundance, researchers have spent years looking into different eco-friendly uses for spent coffee grounds. Water decontamination, next-gen batteries, stronger concrete, biodiesel, 3D printer filament, shoes, even biodegradable plastics: upcycled coffee grounds have been used to create all these things.
And now added to that list is insulation. Researchers have found a way to turn coffee grounds into an eco-friendly alternative to petroleum-based products like Styrofoam and spray foam.
As reported by EurekAlert, the study is the work of researchers from Korea’s Jeonbuk National University and was published recently in the journal Biochar. There have been previous attempts to use coffee grounds as an eco-alternative for insulation, but due to its low porosity it has only had a limited efficacy. But for the new substance, researchers converted the spent coffee grounds into biochar.
Biochar is made by subjecting a substance, like coffee grounds, to extremely high temperatures, resulting in a new, carbon-rich and highly porous material. Being more porous allows the biochar to trap air, giving it better insulation against thermal transfer.
To the biochar researchers added ethyl cellulose, a natural polymer created from cellulose, and used what they describe as a “pore restoration” strategy, which kept the polymer from filling the pores in the biochar and thus strengthening the insulative properties.
The resulting material with a thermal conductivity of “0.04 W per meter per Kelvin, a level comparable to commercial expanded polystyrene.” Anything below 0.07 W per meter per Kelvin is considered to be an effective insulator, making the biochar insulation “among top-performing options.”
Like other biochar-based alternatives, the new insulation compound is an ecological double whammy. It’s cheap to make, relying on materials that would otherwise end up in landfills, and replaces traditional options that often require toxic chemical or industrial solvents in order to create.
We are one step closer to achieving my dream: to live in a world made of coffee. My house made of coffee bricks on a foundation made of coffee cement, the walls lined stuffed with coffee insulation, and everything runs on a battery made out of coffee. My animals are all fed with coffee eco-feed and my plants with coffee compost. Everything is beautiful and nothing hurt.
Zac Cadwalader is the managing editor at Sprudge Media Network and a staff writer based in Dallas. Read more Zac Cadwalader on Sprudge.
