Organic Waste Recovery to Reduce Methane Emissions and Food Insecurity

Americans throw out 100 billion pounds of food per year [1]. Sitting in landfills, this food waste becomes methane -- a potent greenhouse gas. Startlingly, we discard 1/3 of the food we produce to generate 1/5 of our annual methane emissions [2]. With better municipal programs to recover organic waste, we can avoid these emissions, convert discarded food into useful materials, and help address food insecurity in our neighborhoods.

Our food waste does get eaten: microbial organisms in landfills feast on our scraps. In doing so, they generate and release methane [3], which is 30x more potent than carbon dioxide as a greenhouse gas [4]. It's a utilitarian jackpot to avert these emissions while generating useful materials, supplying local jobs, and combating hunger.

From our food waste, we could make biogas or compost [5]. Biogas is fuel made from rotting food; it is an ideal "transition fuel" because it can be used directly in heating applications or refined into natural gas [6]. Compost is a soil additive made from rotting food; it can boost agricultural yields while reducing fertilizer use [7]. With composting, we avert emissions and help replenish our soil. With biogas, we put inevitable emissions to good use and prevent additional burning of gas or coal. Waste collection and re-use represents one of many opportunities to build a "circular economy."

Local supply, demand, and infrastructure should determine whether a municipality pursues biogas generation or composting. Large enough cities should have waste collection centers doing both. Integrated facilities improve efficiency with complementary biogas and compost production because different types of waste are better suited to one of the two end uses [8, 9].

Integrated organic waste processing is already done in Vancouver, Portland, San Jose, and elsewhere. Yet nationally, the volume of disposed waste has been increasing while recovery has remained below 40% [10]. Within the agricultural sector, a fifteen-year trend of rising investment in waste processing facilities has stalled sine 2014 [11].

Moreover, these efforts are rarely prioritized when local budgets are strained. For example, New York City's composting was defunded at the start of the COVID-19 pandemic [12] along with all but one other city department.

Finally, there is the sardonic juxtaposition of food waste and food insecurity. So much edible food is discarded, yet 1 in 10 American families are food insecure [13]. Municipal collection of organic waste could salvage edible remains and streamline the reclamation of food for those in need.

If you want to reduce your waste footprint, the EPA offers many resources to facilitate individual action. Readers with the space and resources can compost their food waste at home. Others can contribute to local programs in waste recovery or support participants in the Food Recovery Challenge.