Sustainable Aviation Fuel (SAF) is no longer a theoretical idea. With the UK SAF Mandate now in force, growing pressure to decarbonise aviation, and increasing interest in domestic fuel production, attention is turning to the practical questions. Where could SAF be produced domestically? Which feedstocks are realistic? And what would need to be in place for such projects to work?
Residual municipal solid waste (black bin bag waste) is one of the feedstocks often discussed in this context. On paper, the idea is attractive. Residual waste already exists at scale, existing disposal routes are facing increasing policy and cost pressures, and waste-derived fuels could help connect circular economy objectives with aviation decarbonisation.
However, Waste-to-SAF is not simply a technology question. It sits between waste management, aviation fuel supply, industrial infrastructure, planning, logistics, policy and commercial delivery. For local authorities, airport regions and waste partnerships, the key question is therefore not just “could waste be converted into SAF”, but rather “could this work here?”
That is the question City Science has been exploring through an Innovate UK-funded project with the Heathrow Strategic Planning Group (HSPG). The project developed a practical screening framework to help assess whether a region has the right combination of feedstock, sites, infrastructure, policy conditions and delivery partners to support future Waste-to-SAF development.
Rather than producing a generic assessment of Waste-to-SAF technology options, the work focused on place-based feasibility. It brought together waste arisings, waste composition, future policy scenarios, site constraints, infrastructure requirements, logistics considerations and commercial delivery models into a single framework for early-stage strategic assessment.
The result is an approach that can help move Waste-to-SAF discussions from high-level interest to practical evidence. It can support local authorities, airport regions and infrastructure stakeholders to understand whether an opportunity is credible, what constraints need to be resolved, and what the next stage of engagement or feasibility work should focus on.
Why local context matters
Residual waste management is entering a period of significant change. Simpler Recycling reforms, Extended Producer Responsibility, the Deposit Return Scheme and the inclusion of Energy from Waste in the UK Emissions Trading Scheme are all expected to influence the composition, volume and economics of residual waste over time.
Residual waste is also increasingly being viewed not only as a disposal challenge, but as a potential resource for low-carbon fuels, chemical recycling and other industrial pathways. This creates new opportunities, but also adds uncertainty around availability. The same waste streams may become increasingly contested between existing disposal routes, emerging recycling technologies and future fuel production pathways.
For organisations interested in Waste-to-SAF, this means that high-level waste tonnage figures are not enough. A credible assessment needs to consider whether suitable material is available, how that availability might change, whether waste can be aggregated at sufficient scale, and whether the economics could remain viable over the long term.
This is where the assessment can quickly become complicated. The relevant information often sits across waste contracts, disposal data, planning constraints, infrastructure maps and policy assumptions, and it is not always held in one place or in a consistent format.
By combining waste arisings and composition data, the framework helps identify whether a region has enough suitable feedstock to justify more detailed SAF feasibility work, or whether wider regional aggregation would be needed. This is an important step because commercial-scale facilities are unlikely to rely on a single local authority waste stream alone.
The HSPG case study reinforced this point. While individual authorities may be able to support early-stage or smaller-scale scenarios, larger commercial opportunities are likely to require collaboration across wider waste catchments. This makes regional partnership, long-term feedstock visibility and alignment with future waste strategy central to any credible Waste-to-SAF proposition.
From technical possibility to practical feasibility
Much of the public discussion around SAF focuses on production technologies and fuel chemistry. These are clearly important, but they are only part of the picture.
A Waste-to-SAF project also needs access to reliable feedstock, suitable industrial land, transport connections, fuel logistics infrastructure, blending and distribution routes, credible offtake arrangements, and a commercial model that can sit alongside existing waste contracts and disposal infrastructure.
The framework developed by City Science is structured around four connected questions:
- Is there enough suitable feedstock?
- This includes assessing residual waste arisings, material composition, future policy impacts and the potential need for wider regional aggregation.
- How might Waste-to-SAF compare with future disposal options?
- This includes considering the changing cost and policy context for landfill, Energy from Waste and other competing routes.
- Where could a facility realistically be located?
- This includes identifying industrial land, planning constraints, environmental designations, transport access and proximity to relevant infrastructure.
- How could a project actually be delivered?
- This includes considering the roles of local authorities, waste operators, airport stakeholders, fuel suppliers, developers and investors.
For early-stage decision-makers, the value of the framework is that it turns a broad technology opportunity into a set of practical tests. These tests can help determine whether further feasibility work, partner engagement or investment case development is justified.
Infrastructure and logistics are central
One of the key findings from the HSPG work was that Waste-to-SAF should not be assessed only by looking at the location of waste arisings or the proximity of an airport. In many cases, access to industrial land, fuel handling infrastructure, blending facilities, utilities and transport connections may be more important than physical proximity to the airport itself.
This matters because airport regions are often densely developed, heavily constrained and difficult places to accommodate large industrial fuel production facilities. A wider regional view may therefore be required, looking at industrial clusters, port infrastructure, rail freight routes, existing waste logistics and fuel distribution networks.
The HSPG example highlighted the value of considering waste logistics and fuel logistics together. Existing waste flows already move across regional boundaries to access treatment capacity, while emerging fuel infrastructure may develop in locations that are better connected to ports, terminals, industrial clusters or blending facilities.
For example, the development of SAF blending infrastructure at Redcliffe Bay near Bristol shows that fuel distribution and blending assets are becoming an important part of the wider SAF delivery system. This type of infrastructure context is highly relevant when considering where future waste-derived SAF production could realistically connect into the market.
The HSPG site screening exercise, shown below, illustrates how spatial analysis can be used to identify potential opportunity areas while also accounting for major constraints such as environmental designations, flood risk, green belt, existing infrastructure and transport access.
(Click to view map details)
Why local authorities have a central role
Waste-to-SAF will not be delivered by local authorities alone. In most cases, councils are unlikely to be the project developer, fuel producer or investor.
However, local authorities and waste partnerships are often the organisations closest to the waste data, contracts, planning constraints and local infrastructure decisions that shape whether an opportunity is realistic. They also understand the practical pressures around waste disposal, procurement cycles and regional collaboration.
For local authorities, the value of this place-based framework is that it helps translate an emerging technology opportunity into practical strategic questions:
- is there enough suitable residual waste to justify further feasibility work?
- would feedstock need to be aggregated across a wider region?
- how could future recycling reforms affect available waste volumes and composition?
- where might suitable industrial sites exist, and what constraints apply?
- how might future disposal costs and policy changes affect the case for alternative pathways?
- which other partners would need to be involved?
This helps authorities interested in exploring Waste-to-SAF opportunities to understand where they may need to act as convenors, commissioners, planning bodies, data owners, waste system managers or regional partners.
The framework can also support a clear decision not to proceed. In some areas, limited feedstock, constrained sites, weak logistics, uncertain economics or competing waste priorities may mean that Waste-to-SAF is unlikely to be a credible local opportunity. Reaching that conclusion early is valuable, because it helps avoid committing time, cost and political capital to proposals that are unlikely to progress.
For areas where the conditions appear stronger, the same framework can support the next stage of activity. This could include partner engagement, market testing, funding bids, investment case development, waste strategy review or more detailed technical feasibility work.
HSPG as a proof-of-concept
The work with the Heathrow Strategic Planning Group provided a practical test case for the framework. The area has a clear connection to aviation demand, significant surrounding waste arisings, complex local authority and waste management structures, and substantial land-use and infrastructure constraints.
By applying the framework in this context, the project demonstrated how Waste-to-SAF feasibility can be assessed in a more integrated way. Rather than looking at feedstock, sites, economics or delivery models in isolation, the work brought these factors together to show how they interact in a real geography.
This is where the approach has wider value. The same framework can be applied to other airport regions, local authority areas, waste partnerships and industrial clusters. Each place will have a different mix of waste arisings, infrastructure assets, policy drivers, site constraints and commercial relationships. The value of the framework is that it provides a structured way to test those local conditions.
For some regions, the answer may be that there is a credible opportunity to explore further. For others, the conclusion may be that the opportunity depends on wider collaboration, infrastructure development or policy change. In either case, the framework helps turn ambition into evidence.
Supporting the next stage of SAF delivery
The UK SAF sector will need credible feedstocks, investable projects and practical delivery models. Waste-to-SAF may have a role to play, but only where the right local and regional conditions exist.
Early-stage screening is therefore important. It can help stakeholders understand what is realistic before moving into detailed engineering, procurement or investment activity. It can also help identify the partnerships that would be needed between local authorities, waste operators, airport regions, fuel suppliers, infrastructure developers and government.
City Science’s work provides a practical way to support this process. By combining spatial analysis, waste data, policy review, infrastructure assessment and commercial thinking, we can help local authorities, airport regions and waste partnerships test Waste-to-SAF opportunities in their own geography.
For some places, that may lead to more detailed feasibility work, partner engagement or funding bids. For others, it may show that Waste-to-SAF is not the right route, or not yet.
Either way, that is useful. Waste-to-SAF is not a simple solution, and it will not be suitable everywhere. But where there is serious interest, the next step is to move beyond generic ambition and ask a more practical question: