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Leapfrogging anaerobic digestion: tackling the food waste challenge

Engagement Manager

From plate to planet: reducing food waste for a sustainable future

Globally, one-third of food produced for human consumption is wasted every year. If food waste were a country, it would be the third largest emitter of greenhouse gases (GHGs) after the US and China. Food waste not only produces emissions, it causes overuse of natural resources, inflates food prices through excessive demand, and exacerbates food insecurity. Therefore, tackling the food waste challenge is a triple win: it alleviates pressure on the environment, increases margins for businesses, and reduces food prices for households.

In the UK, approximately 10 million tonnes of food waste are produced each year. Some of the UK’s food waste goes directly to animal feed and compost, but the vast majority ends up in landfill or in anaerobic digestors (AD). Food waste rots in landfill and produces methane (80 times more harmful than CO2). Whilst AD is a significant step up from landfill as it can produce biogas, electricity, and fertilizer, the EU Waste Hierarchy ranks it as one of the last options for disposal (putting waste prevention, reuse, and recycling first).

Here’s why we need to shift away from AD:

  1. It’s not solving the problem; it’s perpetuating it. Food waste is still being generated and supermarkets and manufacturers are less incentivized to prevent it.
  2. AD is primarily larger scale and centralised; AD facilities are generally located far away from the point of waste generation. One study discovered that a single farm used 220,000 litres of diesel of fuel a year for transporting farm food waste to AD.
  3. Toxic spills. In 2019, spillages of solid and liquid non-digestible AD waste were attributed to more than 10,000 fish deaths in a UK river.
  4. Whilst AD captures gas, the combustion of gas into usable heat generates nitrogen oxides, sulfur dioxide, and carbon monoxide.
  5. Compared to a traditional power plant, AD facilities charge the waste producer to deliver the waste and process it. The burden of these costs is, of course, eventually passed on to the consumer. Furthermore, AD is subsidised by the government – another burden on the taxpayer.

Acknowledging the impact of food waste, entrepreneurs are developing a range of innovative technologies.  Chip[s]board   is processing food production by-products, including potato peelings, to produce bioplastics.  Better Origin   is converting similar feedstocks into poultry feed by feeding it to protein-rich black soldier fly larvae which can multiply their bodyweight 5,000 times in just a couple of weeks, and then provide a rich source of protein for animal feed.

Whilst these technologies address “post-production” sidestreams from the manufacturing site, the hardest nut to crack is processing the main waste stream - household waste – where 80% of food waste is generated. As with most recycling technologies, “if garbage goes in, garbage comes out”; technologies largely rely on a specific mixed blend of post-production waste e.g. peelings, offcuts, and post-harvest residues. Solely tackling these relatively small post-manufacturing waste streams is not enough.

Ultimately, avoiding household waste requires a shift in consumer behaviour. Some technologies are supporting better food waste behaviour. For example, Olio  allows households to give their surplus ingredients to neighbours.  Too Good to Go   allows consumers to fight food waste by distributing surplus restaurant food to consumers for low prices. If you’re struggling to use up the ingredients in your fridge, the  Myfoodways  app formulates recipes based on your ingredients, and  Fridgecam  allows you to convert your fridge into a “smart fridge” by installing cameras which connect to an app so you can avoid doubling up on ingredients.

Nevertheless, while technology can aid the consumer into making the right choices, more action is required to raise awareness of the problem itself; educate the consumer, and increase the way we value food. As the human population is set to increase more than 35% in the next 30 years, the UN estimates that we will need to double food production by 2050 without taking any more land from nature. In order to achieve this, humans must build a greater connection with the land and supply chains which support our very existence.

To leave you with a quote from ecologist and conservationist, Aldo Leopold, “There is value in any experience that reminds us of our dependency on the soil-plant-animal-man food chain [...] Civilization has so cluttered this elemental man-earth relation with gadgets and middlemen that awareness of it is growing dim. We fancy that industry supports us, forgetting what supports industry. Time was when education moved toward soil, not away from it.”


  1. 15 Emerging Technologies Helping Reduce Food Waste   (2023)
  2. Six Reasons Anaerobic Digesters Aren’t as Environmentally Friendly as You Think   (2021)
  3. Aldo Leopold, Sand County Almanac (1949)