Why is this research needed?

Two Energy from Waste (EfW) plants have been selected for Track 1 government support, to add CO2 capture to their facilities by 2027 and then store CO2 in the Irish Sea as part of the North West Hynet industrial cluster. The waste sector increasingly appears as a low-hanging fruit for the deployment of Carbon Capture and Storage (CCS) facilitated by high load factors, a typical CO2 capacity (0.3-1 MtCO2/yr) ideal for scaling up the technology and the prospect of new revenue streams by monetising Carbon Dioxide Removal (CDR). This consists of piping compressed CO2 from post-recycling, residual waste feedstock, much of which originated as atmospheric carbon, to permanent storage in disused natural gas reservoirs a kilometre or more under the seabed.

Post-recycling residual waste provides a domestic resource of biomass, not directly distorting food production, and may become a premium resource for CDR. Yet, other uses will compete for the resource to produce energy vectors with less, or no, associated CDR, e.g. subsidies from the Department of Transport for up to five waste-derived Sustainable Aviation Fuels production facilities by 2025. And at the same time there are other policy objectives to reduce UK waste generation by 50%.

To ensure that, in particular, government policies are informed by robust evidence, and businesses can undertake fully representative analyses of proposed projects, this study develops a new framework to analyse these complex options. In particular, it will use best emerging practices in Life Cycle Assessment to conduct a comparative assessment of the use of waste to remove excess carbon dioxide from the atmosphere and the use of waste to produce Sustainable Aviation Fuels.

The project output will quantify three direct output of waste use for climate purposes: direct emission reductions, avoided CO2 emissions by displacing or replacing other activities and the removal of excess atmospheric carbon dioxide. It is crucial that policymakers and the private sector can value climate output of waste use differently to develop policies that maximise climate benefits in a net zero economy.

The project will be a stepping stone to provide the tools to review how society values the fraction of waste containing biomass and start reconciling principles of the circular economy and maximum climate benefits. This includes taking an approach where future CO2 emission reductions and the future availability of non-biomass Carbon Dioxide Removal are embedded in Life Cycle Assessment (LCA) and decision-making, instead of using static, historical data in LCA databases.

A first example is accounting for expected reduction in the carbon intensity of electricity (or heat) generation when evaluating the displacement of grid electricity (or heat) by Energy from Waste plants with CCS. A second example is the comparison of Sustainable Aviation Fuels with conventional aviation fuels and the re-capture of combustion emissions with Direct Air Capture.

What is this research investigating?

This research proposes that using waste with CCS in Energy from Waste (EfW) plants offers more significant climate benefits compared to alternatives like waste-derived Sustainable Aviation Fuel (SAF). To test this hypothesis within the UK context, the project will conduct a direct comparison of these two approaches.

This project has two main purposes.

1) Develop a new framework to determine the best uses of the biogenic fraction of waste as a climate reversal tool. Key features of the methodology are:

o Consider post-recycling, residual waste as a commodity to discount the climate impacts of landfilling, as it is gradually being phased out
o Use best emerging practices in Life Cycle Assessment (LCA) to examine separately
– avoided CO2 emissions created by the displacement of other commodities or activities
– direct GHG emission reductions
– atmospheric Carbon Dioxide Removal (CDR)
o Use system expansion, energy allocation methods and principles of consequential LCA to account for multiple energy vector production from waste – avoiding reported flaws of attributional LCA studies examining a single use of waste
o Integrate the decarbonisation of key commodities, e.g. electricity, heat, primary metal production, avoiding flaws of LCA studies using historical data on, for example, the average carbon intensity of domestic or industrial heat
o Integrate the availability of CDR outside of the waste sector in decision-making

2) Use this methodology, for a timely contribution, to provide robust evidence of a comparative assessment of:

o UK government support for the first commercial deployment of CCS on Energy from Waste plants
o UK government support for the first commercial deployment of waste-derived Sustainable Aviation Fuel production.

The project results will be rapidly disseminated via the readership and social media engagement of the Oxford Institute for Energy Studies OIES, and directly communicated to key stakeholders in government and in regulatory agencies by the investigators. When the project is completed, the new framework can be readily adapted to assess other climate relevant uses of waste in subsequent projects, and, if combined with material flow analysis of the UK waste resource, examine ways to rethink the waste hierarchy to maximise the climate benefits of biogenic carbon in the UK waste resource.

What does the research hope to achieve?

Beneficiaries for the work include:

a) Most actors in the waste management sector, waste management companies and the trade associations representing them, such as the UK Environmental Services Association or the EU Confederation of European Waste to Energy Plants. This also includes all actors in the waste management chain, from waste collection, to recycling to Energy from Waste plant owners and local authorities operating landfill sites. They need independent indications of existing and new policies to make commercial decisions.
b) Regulators with a remit covering waste management and energy vectors produced from waste. This includes the Department for the Environment, Food and Rural Affairs, the Department for Energy Security and Net Zero, the Department for Transport and the Office for the Environment. They need independent evidence of the best uses of waste in the context of a net zero economy and evidence on a re-assessment of the current regulatory environment, such as the waste hierarchy, after years of rapid policy shifts.
c) Local authorities being charged gate fees by waste management companies for waste disposal. They need independent evidence of new revenues from waste valorisation, such as SAF or Carbon Dioxide Removal to be in a position to negotiate future gate fees.
d) Commercial developers/owners of Sustainable Aviation Fuel plants and Energy from Waste plants, including those developing CCS in Track 1 and subsequent industrial clusters.
e) The emerging sector of voluntary and compliance carbon markets will benefit from a more robust understanding of the possible contribution of the waste sector to carbon dioxide removal.
f) The aviation sector, and, in particular, airlines as future users of waste-derived SAF.
g) Academic researchers, who will be able to extend the methodology, expand research output on climate benefits and develop new thinking on the treatment of biogenic carbon within the waste hierarchy
h) Non-Governmental Organisations with a focus on sustainability, the circular economy, decarbonisation, energy and/or waste, who may use independent evidence to review their position towards current principles of the circular economy.
i) The UK public who will benefit from maximising the net climate benefits of a domestic resource of biogenic carbon.

Principal outputs from the project will be:
D1.2 LCA model output of waste-derived SAF production
D2.2 LCA model output of an Energy from Waste plants with CCS
D3.1 A Life cycle sustainability model framework to compare CCS and SAF
D4.1 A final technical report to summarise findings for key stakeholders
D4.2 A white paper and a 30 min podcast on mainstream platforms for public outreach