Portsmouth City Council has pledged to reduce Portsmouth’s scope 1, 2 & 3 emissions to NetZero by 2030. Part of reducing carbon emissions in the city involves reducing the amount of waste generated in the first place and also improving how that waste is dealt with once it reaches the bins by: improving recycling facilities and processes and introducing food waste collection.
Why do we need food waste collection?
In Portsmouth, 40% of non-recyclable rubbish going into the black bins/bags is food waste. When rubbish is collected on the kerbside rounds, it is taken to the Energy Recovery Facility (ERF) to be incinerated. The heat produced from the burning of rubbish creates steam and by turning turbines, generates electricity. The ERF in Portsmouth supplies up to 14MWs of electricity to the National Grid, enough for around 20,600 local homes. By processing waste through the ERF, we are able to avoid sending waste to landfill and reduce harmful greenhouse gas emissions. Only around 4% of waste in Portsmouth is sent to landfill, which includes materials not able to be processed through incineration.
Although we recover energy through incinerating rubbish, anaerobic digestion is the best way to process food waste. This is because it halves the amount of carbon dioxide emissions when compared to ERF. Anaerobic digestion is where micro-organisms break down the waste into biogas and a nutrient-rich fertiliser. The biogas (carbon dioxide and methane) can be converted to heat and/or power, and the fertiliser can be used to improve soil quality; sequestering large amount of carbon as it is added to the soil.
Research shows that by collecting food waste, households tend to reduce the amount of food waste that they generate. This is because it becomes more obvious how much food is being thrown away each week, leading to a shift in behaviour. This is good news for the environment, as no solution for processing food waste, is as good as not creating the waste in the first place!
Why is Portsmouth different?
Portsmouth is the second Council in Hampshire to collect food waste, after Eastleigh. A Waste Composition Analysis (WCA) was carried out in 2018 and found the kerbside rubbish contained 40% food waste. In comparison, the WCA found mixed plastics equated to 9.7% of rubbish (not currently collected in Portsmouth). This is why PCC wanted to focus on food waste as it makes up such a large amount of the waste in the rubbish bins/bags.
The food waste collection trial was introduced in September 2019, with around 8,000 homes initially on the service. In October 2020, a further 10,000 homes were added, taking to total to nearly 20,000. Since starting the trial, 20% of waste collected in the trial areas has been diverted from energy recovery to anaerobic digestion.
A survey will be provided to residents in the second trial areas to give feedback sometime in the New Year. This survey, along with the results of the first one, will help shape the future of food waste collections in Portsmouth.
What you can do?
The council are actively seeking ways to roll out food waste collections city-wide for domestic properties. You can also try cutting down your household’s food waste by meal-planning, freezing where possible, researching left-over recipe ideas and more. Visit Love Food Hate Waste for more tips on keeping food fresher for longer, and tasty recipes to use up your leftovers.
By Rebecca Adams
Waste Collection & Disposal Guest Blogger