Can Energy from Waste drive the deployment of Carbon, Capture & Storage?
Comment by Susanna Elks
Energy Policy Advisor
Few industrial sectors in the UK can boast a pipeline of construction projects that will double capacity in the near future.
Energy from Waste (EfW) is booming, but could it also help drive the development of a technology likely to be essential to meeting our climate change targets – Carbon Capture and Storage (CCS)?
Fitting CCS energy to the growing number of EfW plants could not only further decarbonise the waste sector, but also provide a stream of early, investable projects to support wider CCS rollout.
Energy Systems Catapult recently published Innovating to Net Zero which found that Carbon Capture and Storage (CCS) will be vital in meeting the UK emissions target.
Most CCS analysis has focused on its application for large-scale power and hydrogen production, or to reduce emissions from industrial sectors (like cement and chemicals manufacturing).
Yet carbon emissions from EfW plants in the UK already exceed the cement and chemical industries and are almost on a par with emissions from refining iron and steel. That figure is set to nearly double based on new EfW plants in construction or development – so fitting them with CCS could support economy-wide decarbonisation.
Get the incentives right and we could drive innovation in a technology for a growing domestic and export market and reduce residual emissions from waste. But get them wrong and we could divert waste to landfill or away from waste reduction, reuse and recycling measures.
The results indicate that EfW plants should be considered alongside industrial emitters and generators in future CCS Government policy, and as an option for future waste disposal decarbonisation.
Note: the analysis was commissioned by BEIS in an 80% emissions context, but subsequent Net Zero analysis has only added to the emphasis on tackling residual emissions such as those from EfW plants.
Energy from waste plants – large carbon emitters
At the end of 2017 there were 40 EfW plants in operation in the UK, emitting approximately 11 Mte CO2 of total UK emissions, which is more than the cement and chemicals industries and almost on a par with emissions from refining and iron and steel.
These plants produce electricity with a carbon intensity of around 600g/kWh. This is roughly 50% higher than a typical combined cycle gas turbine (CCGT), and much higher than the current grid average of around 220g/kWh.
Nevertheless, EfW plants are judged on balance to have better environmental credentials than landfill, which emits methane from biodegradable material. It’s still critical to maximise reuse and recycling, but EfW plants may be the best solution for residual waste disposal
Could we reduce emissions by reducing the volume of waste?
Looking forwards there is increasing policy emphasis on creating a circular economy. This includes proposals to reduce initial waste (particularly food and plastic) and increasing both recycling rates and rates of separate food waste collections for anaerobic digestion.
These could all significantly alter the waste disposal landscape. However, it is anticipated that even with reduced waste and improved waste management, there is still likely to be a large residual waste stream to deal with, as shown by the inclusion of EfW plants in the Committee on Climate Change’s assessment of Net Zero.
Energy from waste with CCS as a potential solution
With the number of EfW plants projected to increase, emissions are set to rise from 11MtCO2/year to 20MtCO2/year. Tackling these emissions will be critical in delivering a Net Zero economy.
One possible solution would be to fit these plants with CCS technology. Our assessment showed this could be economically comparable to other potential CCS applications, with some unique advantages:
EfW plants have a higher proportion of CO2 in the flue gas than some comparable emitters, which improves the efficiency of CCS thereby reducing project costs.
EfW plants are by far the youngest set of large emitters in the UK. Most units are under 6 years old, while most UK energy intensive industries are at least a generation older. The higher reliability and longer remaining lifetimes of EfW plants (and lower exposure to international competition) could make CCS investments more attractive.
The technology also has the potential for widespread export, with the current European waste incineration fleet emitting around 90MtCO2e/year and the USA fleet around 32MtCO2e/year.
However, despite being a key enabler of a Net Zero economy, CCS technology is not yet financially viable (under current market arrangements). Progress in the UK and internationally has so far been stop-start.
Most recently, UK Government has laid out its goal of CCS being available for widespread deployment by 2030 and committed at least £800m for CCS in the recent Budget. It is likely that this funding will support the creation of ‘low carbon industrial clusters’; areas where multiple emitters are fitted with CCS and share carbon transmission and storage assets.
Our assessment showed that several EfW plants are located in the areas which have been highlighted as potential low carbon clusters. The addition of EfW plants could support clusters by both increasing and diversifying the users of the transmission and storage assets as highlighted in the figure below.
Figure 1: Charts showing the relative size of key emitters in two Industrial Clusters
CCS on EfW plants presents a longer-term opportunity. The Catapult’s national whole system model ESME, assesses options for decarbonising the UK economy and chooses the best solutions on the basis of the lowest system transition cost.
Given the option of fitting CCS to EfW plants, ESME builds the maximum allowed number of EfW plants, choosing to deploy CCS earlier than in the scenario without this additional option. This led to 20% of all CO2 captured in the UK being derived from EfW plants by 2050. This suggests EfW with CCS could be a powerful and cost-efficient way of supporting economy wide decarbonisation.
How do we incentivise the best outcomes?
A preliminary financial assessment suggests EfW with CCS could be economically comparable to standalone EfW plants at a carbon price of £90/tCO2e or a CfD strike price of £136/MWh with a carbon price of £45/tCO2e. This is subject to several uncertain assumptions, but these values along with sensitivity analyses conducted for this work, show that the costs of fitting EfW plants with CCS are comparable to other CCS applications.
However, as there is currently no carbon price applied to EfW plants and no way of rewarding negative emissions, the current policy environment is unlikely to drive deployment. Furthermore, because the receipts from power sales are a lower contributor to revenue than gate fees (the money EfW plants get for disposing of waste), support schemes linked to electricity generation may not be best placed for EfW plants.
As this technology bridges multiple sectors, creating the right incentives for EfW plants with CCS will require careful coordination:
Firstly, incentives must not be placed on EfW plants which lead to increases in emissions by diverting waste from EfW plants to landfill, i.e. exposure to carbon prices.
Secondly, it is important this does not create perverse incentives whereby more waste is created and incinerated/gasified than is necessary, ie. that could be recycled or reused.
Finally, ‘gasification’ has been highlighted as a potentially valuable technology for increasing the efficiency of EfW plants, and it is current Government policy to drive this. Importantly, gasification could also produce a step change in efficiency for fitting EfW plants with CCS, due to the CO2-rich flue gas it produces. Therefore, a coherent policy approach is needed to align incentives for gasification and incineration plants in line with their system value. Our recent project Rethinking Decarbonisation Incentives (RDI) explored how UK policies can promote clean growth by taking a ‘whole systems’ perspective on carbon policy.
Addressing these factors could help EfW with CCS become an attractive opportunity as we look to tackle residual emissions across all parts of the economy on the road to Net Zero.
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