By Dr Phoebe Cochrane, LINK’s sustainable economics officer
Official figures released last week show a 72 percent rise in the amount of waste burned between 2018 and 2019. The increase is largely due to more household waste being incinerated, instead of being landfilled, and corresponds with several new incinerators becoming operational during this period.
This trend is likely to continue as waste is diverted from landfill ahead of the ban of biodegradable municipal waste to Scottish landfills in 2025. Scotland has six operating incinerators, also known as Energy from Waste (EfW) plants, and this number could double within the next few years. Is this a wise trajectory, compatible with net zero ambitions?
A new report by Zero Waste Scotland, ‘The climate change impacts of burning municipal waste in Scotland’, looks in detail at the carbon emissions associated with energy from waste. Based on analysis of the plants operating in Scotland in 2018, it found that sending one tonne of residual waste to EfW emitted, on average, 219 kgCO2e. The average carbon intensity of energy produced was found to be nearly double that of the UK grid average (509 gCO2/kWh compared to 270 gCO2/kWh). The report shows that this is sensitive to technology type, with the one Heat Only plant having a significantly lower impact; and composition of material burnt, particularly plastic content. However, it is fair to say that energy from municipal waste is not low carbon.
Incineration has also been shown to impede improvements in recycling rates, since often some of the material burnt could have been recycled or composted. The fear is that building more incinerators will further hamper efforts to increase re-use and recycling and reduce our residual waste, as the companies contracted to run incinerators require councils to provide them with ‘fuel’ in the form of waste.
In Denmark, the government has recently decided that, in order to reduce carbon emissions, they need to incinerate less and recycle more. They will be reducing their incinerator capacity over the coming years and redoubling efforts to increase recycling to achieve a ‘climate neutral’ waste sector by 2030.
Although desirable, it is unrealistic to think that we will be able to use or recycle all our waste – with the best will in the world, we are going to be left with some residual waste; so we do need a plan of how to treat it. A recent report from Zero Waste Europe provides what appears to be a practical solution: Material Recovery and Biological Treatment (MRBT) that combines biological treatment, to stabilise fermentable materials still included in residual waste, with sorting, to recover materials which can be recycled. This ensures that the negative impacts of residuals are reduced when landfilled, and at the same time keeps the flexibility required to continuously improve the performance of waste management systems.
The Zero Waste Scotland report mentioned above looks at various scenarios for managing our residual waste and finds that a strategy that includes this approach could offer the lowest greenhouse gas impacts, but notes that more research is needed.
It is also worth considering the fiscal environment. Should we be taxing waste going to incineration in the same way as we do for landfill, as is done in the Netherlands and Sweden? The Scottish Government does not currently have the powers to introduce such a tax, but the subject was twice debated at the beginning of this year at Westminster, with cross-party support for an incineration tax and a halt to new investment in energy-from-waste facilities.
Scottish Environment LINK has called on the Scottish government to focus on reducing waste through developing a more circular economy and increased re-use and recycling, and and we urge it to develop a waste strategy that is in line with our net-zero and circular economy ambitions.
We will be holding a webinar on November 10th to discuss management options for residual waste. If you are interested in taking part, please contact phoebe@scotlink.org.