Wasted food is a huge but complex problem involving different challenges at each step in the value chain (see graphic above). As the food moves closer to the consumer, each unit of waste represents a more significant footprint in terms of energy and other resources. And then if the wasted food ends up in a landfill where it is converted into methane, it has an even more problematic greenhouse gas footprint. Overall, it is estimated that 100 million tons of food are wasted each year, and that it is responsible for 8% to 10% of US greenhouse gas emissions.
For the wasted food that can’t be prevented, avoided by donation, or used for animal feed, the best possible outcome is to put it into an anaerobic digester. There it is intentionally converted into methane which is then captured and used as a low carbon version of natural gas for various energy needs. Anaerobic digesters have been used for some time, particularly at large animal production facilities where they convert manure into energy. There are also on-going efforts to make that solution available for small dairy operations through their coops, and there are examples of arrangements in which retail level wasted food can be processed in a dairy-based digester.
Different wasted food reduction and mitigation strategies are needed at each step along the chain. A rather substantial amount of 40% of wasted food occurs at the grocery retail level when food might be inadvertently over-stocked, when it doesn’t sell before its “best by” date, or when it isn’t a good candidate for donation or some sort of in-store cooking option.
There is a company out of Concord, Massachusetts called Divert that focuses on wasted food solutions for retail, and its stated goal is to Protect the Value of Food(tm). The company built its first full scale anaerobic digestion facility in Compton, California in 2012 working with Kroger
The Divert business model is to contract with a national or regional retail chain to prevent their wasted food. Divert uses “reverse logistics” to deal with their store-by-store waste flow. They collect and bring back containers of wasted food from each store using one of the same delivery trucks that delivered goods to the store, thus reducing the transportation footprint. They have developed highly efficient “depackaging” technologies to separate food from containers as needed and then recycle what came from that process.
Divert also uses IOT
Divert is making carbon negative energy out of waste that would otherwise be harmful to the environment. By diverting wasted food from the landfill, a net reduction in equivalent GHGs is achieved. The process ensures that wasted food’s embedded energy is captured instead of released into the environment decomposing at a landfill. Converting this food waste into RNG has the added benefit of eliminating the GHG emissions that are generated by the production and usage of fossil fuel natural gas, further adding to the net negative carbon intensity.
Source: https://www.forbes.com/sites/stevensavage/2023/03/14/a-company-producing-carbon-negative-renewable-energy-from-what-would-have-been-wasted-food/