How Leftover Food Can Turn Into Fuel For Your Car

Among the many issues contributing to climate change, our gas-guzzling cars and wasteful food system are high on the list. Around one third of all the food produced in the world gets wasted every year, according to the United Nations' Food and Agriculture Organization, totaling 1.3 billion tons. 

This food waste then builds up in landfills and releases methane, which thirty times worse for the environment than carbon dioxide. Additionally, cars and trucks emit around 24 pounds of carbon dioxide for every gallon of gas, accounting for nearly one-fifth of all U.S. emissions. Wouldn't it be great if we could eliminate both those issues in one fell swoop?

As it turns out, we may be able to fuel our cars with leftover food. A new study published in the Journal of Cleaner Production has outlined a way to convert organic waste destined for the landfill (including food, paper, wood, and yard waste, for example) into a fuel source for vehicles. Using anaerobic digestion—the process of microorganisms breaking down biodegradable materials without oxygen—energy producers could create biogas and renewable natural gas from food scraps. 

Plus, using pyrolysis—the process of breaking organic material down at really high temperatures—they can convert garbage in general to renewable natural gas, bio-oil, diesel, jet fuel, and biochar, a charcoal product used to remove carbon dioxide from the atmosphere. 

“Our study shows that using what would otherwise become landfill waste to produce fuel typically generates less greenhouse gases than simply letting the waste decompose,” Uisung Lee, who led this study at the Department of Energy’s (DOE) Argonne National Laboratory, told Laboratory Equipment.

Additionally, these processes could not only reduce the amount of CO2 coming off of cars and methane emissions coming from the landfills we already have, but would also reduce the need to create future landfills—the trash would just go straight into your car, so to speak. And, with so much matter entering the waste stream, we'd have a steady supply of fuel. For instance, in 2014, an estimated 32 million metric tons of food waste ended up in landfills, or about 70 trillion pounds, according to the Department of Energy.

The study also noted the waste needed to produce this fuel can be collected current trash-collecting and sorting infrastructure, which further lowers the cost of producing this energy. 

"These are the areas where we can realize the greatest environmental benefits while also producing transportation fuels," Lee told Laboratory Equipment.