Stop, sort, burn, bury - Should Scotland incinerate waste?
IOM3 CEO Colin Church FIMMM on his review into Scotland’s plan to incinerate a portion of biodegradable municipal waste, so it ultimately avoids landfill.
Scotland has committed to stop sending its biodegradable municipal waste (BMW) to landfill by the end of 2025. To reach this target, it will need to increase its recycling and waste prevention work and send the remaining BMW to incineration. In November 2021, I was asked by the Scottish Government to be the independent chair of a Review into whether the amount of incineration capacity being planned would be right. My report, Stop, Sort, Burn, Bury, was published in May 2022.
The main question I was asked to address was whether Scotland would have enough incineration capacity to manage its residual BMW in 2025 and beyond. Using data from stakeholders and a model created by Ricardo consultants, the analysis suggests there is likely to be a capacity gap in 2025, when the BMW ban comes into force. While this capacity gap could be closed by Scotland achieving its waste and recycling targets, stakeholders raised concerns about the likelihood of achieving these targets, drawing on experience and comparisons with other nations as evidence of what could be possible.
However, the Review’s analysis shows that, in all scenarios modelled, the capacity gap is likely to have disappeared by 2027, and much of the incineration capacity currently planned would not be needed. The Review therefore recommends that Scotland should limit the granting of further planning permissions for incineration infrastructure and develop an indicative cap for the residual waste treatment needed going forward. This should then decline over time as Scotland transitions towards a fully circular economy.
The short-term nature of the capacity gap, balanced against the long-term likelihood of overcapacity, highlighted the difficulty in using infrastructure with long operational lifespans alone to treat residual waste. The Review finds that the risk of lock-in in waste management contracts is genuine and recommends that Scottish local authorities specifically address this within their contracts.
Residual waste management options
The Review recognises that the best form of residual waste treatment is preventing it occurring in the first place, through reducing waste and recycling. It therefore recommends that the Scottish Government does more to reduce the proportion of recyclable materials in the residual waste stream. However, for the foreseeable future, there will be residual waste in Scotland that needs managing in as safe a manner as possible. Based on the feasibility of different treatment options and an appraisal of their social, health and climate considerations, the Review finds that incineration’s current place within the waste hierarchy is correct. Currently, therefore, it is environmentally better than landfill and less desirable than reducing and recycling waste. However, as discussed below, this position is shifting as other factors change.
Health and other impacts
The Review considers the health and social impacts of residual waste management in Scotland. This included a Rapid Evidence Review on health impacts from Public Health Scotland, which confirms its previous view that such impacts are likely to be small.
The Review also considers the impacts on local amenity; the link between deprivation and location of facilities; perception and employment; as well as the Scottish Landfill Communities Fund; and heat and energy offtake. The Review additionally hears from stakeholders regarding the difficulties they have experienced engaging with planning processes and difficult relationships with local facilities. It finds that communities deserve more authentic and committed engagement from local authorities and industry than is currently sometimes the case.
Decarbonisation
The Review reveals that, currently, incineration is less damaging to the environment than landfill. However, increased incineration, changes to waste composition and wider decarbonisation will make this less favourable over time. To assist in monitoring this, the Review recommends that greenhouse gas emissions from incineration are reported separately from other energy-related emissions.
Separate work has been commissioned to inform further consideration of opportunities to decarbonise the residual waste treatment infrastructure sector in Scotland, with the main focus on waste incineration. In the meantime, the Review provisionally recommends improving pre-treatment processes before incineration, with a particular focus on removing plastics from incineration feedstocks. Additionally, the Review provisionally recommends that combined heat and power should be pursued for as many incineration facilities as possible, as well as carbon capture, use and storage.
Next steps
The Scottish Government has committed to responding to the Review’s recommendations in June 2022 (so that may have happened by the time you read this article). The Review has also been extended to look in more detail at the issues around decarbonisation and is expected to report in early 2023.
