Guernsey’s food waste could be treated locally in future instead of being exported for processing if a suitable solution can be provided on-island.
More than 4,500 tonnes of food waste is currently collected every year from local homes and businesses. After initial processing in the waste transfer station at Longue Hougue, this material is exported to a facility in the South of England.
It then undergoes treatment through a process known as anaerobic digestion. That uses micro-organisms to break down the food and produce a gas that can be burned to generate heat and electricity, or used as vehicle fuel. It also produces a nitrogen rich fertiliser.
Guernsey Waste is now inviting initial expressions of interest from any parties, based locally or off-island, who would like to receive the island’s food waste when the current processing contract expires at the end of 2023.
Any change to the current export arrangement and processing will require approval by the States. However Guernsey Waste operations manager Sarah Robinson (pictured) said this does not rule out other treatment options being considered, provided they can demonstrate environmental benefits and value for money.
“Anaerobic digestion is widely considered to be the optimum treatment for food waste, because it will recover valuable energy from the material, as well as other useful biproducts. However we are very open-minded at this stage, and are really keen to hear from any operators or potential operators that could provide a solution for managing the Island’s food waste,” said Miss Robinson.
“If we have proposals for any other forms of treatment, then we can evaluate what benefits they might offer compared to anaerobic digestion.”
When the island’s waste strategy was first approved in 2012, it included plans for an on-island facility for treating food waste, using anaerobic digestion or a similar process. This was subsequently replaced by the current export-based solution, mainly due to the high cost to the States of constructing a local plant at that time.
Sarah said whatever treatment is used, any solution will have to be reliable, with contingencies built-in to ensure continuity of processing. It also has to be flexible to manage fluctuating tonnages, as Guernsey’s waste strategy is focused on prevention and reduction of waste.
The processor will be responsible for ensuring there are adequate outlets for any biproducts from the processing.
In the case of anaerobic digestion, these are generally liquid and solid residues, which can be used as nutrient-rich fertilizers. However this could be restricted in Guernsey due to the limited land available and the potential impact on the water catchment, and may therefore require further treatment.
Any potential operators have until midday on Monday 23 May to submit an initial expression of interest. Full details can be downloaded here, by entering the project code 52509.
Guernsey Waste will review and consider the solutions proposed before inviting formal tenders later this year. A contract is expected to be awarded before the end of 2022, with an anticipated start date of January 2024.
Sarah said this should provide time for an operator to develop any new facilities, should they be required, but Guernsey Waste was open to negotiation on a later start date.
The island’s Waste Management Plan sets out the methods that can be used to treat and process different waste materials. Changes can be agreed by the States, provided it can be demonstrated that an alternative method is able to achieve the optimum environmental benefits at a reasonable cost, which is a legal requirement.