Food-waste recycling programmes are most successfully when there is solid government policy to back them up, such as “pay as you throw”, finds new research from MIT.
“The food system is notoriously wasteful at all levels,” MIT authors wrote in a recently published paper.
According to their findings, some 22 per cent of the municipal solid waste dropped into landfills or incinerators in the U.S. is food that could be put to better use through composting or soil enrichment.
This is a serious figure – and with serious environmental consequences. When food scraps are used for composting, they help enrich soil and reduce emissions of methane from landfills. Diverting food from the garbage bin also significantly reduces the volume of landfill needed in a given area. And recycling food saves towns and cities money by reducing the frequency of trash collection.
“If you remove food from your waste stream, you no longer have to remove garbage so often,” said Jonathan Krones, a visiting scholar in the MIT Department of Materials Science and Engineering.
Krones and his MIT colleagues conducted a survey of 115 mid-sized U.S. cities with populations greater than 100,000 but less than 1 million to get an insight into how to encourage people to recycle food scraps.
In all, 46 of the 115 cities surveyed have active food-scrap recycling programs of various forms, including educational programmes, low-cost home composting bins, drop-off facilities, and curbside collection of food.
Despite the differences between the cities, and the socioeconomic differences within cities from one neighbourhood to the next, the researchers found one common denominator: food-scrap recycling schemes are most likely to succeed if there is a “pay as you go through” policy.
These typically charge residents for exceeding a certain volume of trash, making people more active participants in waste collection by having them limit and sort their own garbage. In other words: financial incentives make people less likely to gripe about separating food from other kinds of trash.
“This finding should make economists happy,” quipped Krones.