Around 40% of local authorities already collect food waste. Whether councils are to amend their current collection service or to introduce it, it is likely to be a big challenge especially if local authorities are required to procure the supporting infrastructure as well. Currently, obtaining vehicles is particularly difficult, as well as caddies, liners and crews. That challenge, coupled with the current economic climate, when councils are having to save money year-on-year, there is no doubt that for some authorities the introduction of food waste collection will be an uphill task.

The scale of waste

In a recent campaign by WRAP, statistics shared about the impact food waste is having on our planet stated that 6.6 million tonnes of household food waste is thrown away in the UK each year.

This food waste is responsible for nearly 25 million tonnes of CO2 emissions, equivalent to 5.4% of the UK’s territorial emissions. The majority, 4.5 million tonnes, is food that could have been eaten and is worth approximately £14bn – or £60 a month for an average UK family.

The amount of waste that needs to be collected is massive and therefore, what to do with the waste will be high on everyone’s agendas. Thankfully, there is a process that can deal with food waste in a cost-effective and sustainable way.

Anaerobic digestion

Anaerobic digestion (AD) is the sustainable process of recycling food waste into green energy and biofertiliser, a nutrient-rich organic material used to fertilise farmland. Food waste can include everything from a used teabag and vegetable peelings to raw or cooked fish and meat. If it was ‘edible’, then it can be digested.

Food waste enters a building where it is processed into a liquid porridge, and then pumped into the anaerobic digestion plant. It is here that bacteria feed on the food waste, breaking it down to produce biogas. Biogas is captured and used as a fuel in Combined Heat and Power (CHP) units to produce renewable electricity and heat or cleaned and sent directly to the gas grid.

The waste is pasteurised to ensure that any pathogens are destroyed and the biofertiliser (digestate) is stored in large lagoons ready to be applied on farmland when the crops require it.

The benefits

It’s cost effective – AD is a low-cost process with opportunities to make savings on landfill taxes or energy from waste gate fees. In a recent report, the Anaerobic Digestion and Bioresources Association said that processing food waste at AD plants could save each local authority up to £1.8m annually, which will be a welcome figure to many budget holders.

It’s eco-friendly – AD is considered top of the hierarchy for food waste above other processes such as composting and it’s a positive step towards being more environmentally responsible.

It’s a renewable form of energy – The biogas created from AD is rich in methane and can be converted into renewable energy (heat and electricity) or injected directly into the gas grid.

Creating organic fertiliser for farmers – Farmers can use the high nutrient biofertiliser produced as a by-product of AD so, at a time when fertiliser costs are at an all-time high, local authorities using AD are supporting their local farmers.

To put it into context, in 2021, BioteCH4 handled 525,000 tonnes of waste across our sites, enough to fill the Royal Albert Hall nearly eight times, producing enough energy to power over 50,000 households. This complex biological process is an opportunity and an ally to local authorities who are facing the 2023 deadline with some uncertainty.

Our recent success

Over the years we have worked with a number of local authorities who have adopted AD as the process to recycle their residents’ food waste and the results have always been positive. One of our most recent food waste trials with a local authority saw us process approximately 80kg per year of food waste for each household on the trial, with between 75% and 85% of residents offered the scheme choosing to use it.

The waste collected and processes through the trial produced around 250m3 of digestate fertiliser which we spread on arable farming land local to our facility.

We generated 54,000m3 of biogas and 135MWh or 486GJ (Giga Joules) of energy as part of the trial period, which is enough energy to heat 4,000 homes for a day or the equivalent of charging over six million mobile phones!

To sum up

The goal of food waste collections for all households by 2023 is a challenging one and whilst we know many local authorities are looking at what this means for them, there are others that have yet to start planning for the challenges ahead.

We would urge any local authority which has not put food waste collection plans in place yet, to start planning for the changes ahead. Anaerobic Digestion is the best solution to the food waste challenge and a positive step towards being compliant, sustainable, and environmentally responsible.

Pamela Woolcock is group public sector lead at BioteCH4.