SAF Feedstock Reality Check 2026: HEFA Limits, Feedstock Competition and the Race for Next-Generation SAF
- Green Fuel Journal
- 4 days ago
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Green Fuel Journal Research & Intelligence Team — see our Editorial Standards and AI Usage Disclosure for how this report was produced and verified.
Published: August 2026 | Report Type: Executive Intelligence — Premium Research
Scope & Disclaimer:
This report is provided for strategic research and informational purposes only. It does not constitute investment, legal, financial, engineering, or safety-certification advice. Company-claimed figures are labelled as such. No reliance should be placed on this analysis for commercial or regulatory decisions. See greenfueljournal.com/disclaimers for full terms.
1. Executive Intelligence Synthesis
Direct Answer — What Is the SAF Feedstock Constraint in 2026? The main SAF feedstock constraint in 2026 is not a shortage of biomass in the abstract — it is a shortage of qualifying, mobilisable, and economically defensible feedstock that can actually reach a SAF refinery as certified, converted fuel. HEFA remains the only commercially mature SAF pathway, but its dependence on oils, fats, and greases creates a structural scaling ceiling. The gap between theoretical resource and delivered, convertible feedstock defines the industry's central strategic problem for the decade to 2035.
SAF feedstock has emerged as the defining strategic constraint in aviation decarbonisation: HEFA — the only commercially mature pathway — is projected to account for 82% of global SAF production capacity by 2030, yet its feedstock model depends on a finite pool of waste oils and fats that is simultaneously contested by renewable diesel and biodiesel. In 2024, 81% of EU SAF came from used cooking oil, with 69% of that supply originating outside the EU and 38% attributed to China alone — a concentration profile that reveals the structural fragility of today's commercial supply base. The UK's SAF Mandate already limits HEFA's eligible share of the blending obligation to 71% by 2030 and 35% by 2040, making pathway diversification not merely commercially advisable but regulatory-mandatory for producers serving the UK market.
The question that will determine industrial winners through 2035 is whether enough qualifying, sustainable, and economically mobilisable SAF feedstock can be secured to support mandatory expansion under binding regulatory frameworks in Europe, the UK, and a growing number of jurisdictions beyond.
This report does not argue that HEFA is simply running out. Its central finding is more precise: HEFA is becoming a feedstock-constrained growth engine. An ICAO-hosted Boeing/ICF market assessment confirms this dominance while explicitly identifying sustainable oils and fats availability as the principal long-term scalability constraint. The European market provides a particularly unambiguous signal: 81% of EU SAF was produced from used cooking oil in 2024, with 69% of that supply originating outside the EU and 38% attributed to China alone.
The analytical framework this report uses to assess each feedstock is the GFJ SAF Feedstock Reality Ladder: a sequential chain from
Theoretical → Recoverable → Collectable → Sustainable → CORSIA/Market Eligible → Contracted → Delivered → Convertible to SAF.
Every rung shrinks the addressable pool. The gap between the top and bottom of that ladder is the intelligence gap this report is designed to expose.
Five Executive Signals
Signal 1
FINDING
An ICAO-hosted Boeing/ICF assessment projects HEFA at 82% of global SAF production capacity by 2030, while the same source explicitly identifies sustainable oils and fats availability as the principal long-term scalability constraint.
SO WHAT
The near-term SAF market is structurally dependent on a single feedstock category — waste lipids — that is simultaneously contested by renewable diesel, biodiesel, oleochemicals, and other demand centres.
NOW WHAT
Industrial strategists must assess how much lipid-feedstock exposure their SAF position carries and at what point that exposure becomes a project-finance liability rather than a commercial advantage.
Signal 2
FINDING
In 2024, 81% of EU SAF came from used cooking oil, 69% originated outside the EU, and fewer than 10 suppliers represented 80% of supply — demonstrating the degree of concentration in the current market.
SO WHAT
Europe's SAF mandate is already importing its feedstock problem: the regulatory demand signal is strong, but the supply base is narrow and geographically exposed.
NOW WHAT
Producers and buyers operating in the EU market should treat feedstock provenance, certification depth, and supplier concentration as primary procurement risks, not secondary compliance questions.
Signal 3
FINDING
The US DOE has assessed that projected yellow-grease supply could satisfy only a small proportion of projected aviation fuel demand, while NREL explicitly warns that the same feedstocks targeted for SAF can be diverted to renewable diesel and chemicals at higher product yields.
SO WHAT
SAF does not compete only against fossil jet fuel — it competes against alternative uses for the same sustainable carbon, making the commercial battleground broader and more contested than refinery capacity figures suggest.
NOW WHAT
Feedstock procurement strategy must account for renewable diesel and oleochemical demand as competing forces, not simply aviation growth.
Signal 4
FINDING
The UK SAF Mandate explicitly limits HEFA's eligible share to 71% of the obligation by 2030 and 35% by 2040, while the EU's ReFuelEU regulation introduces a synthetic-fuel sub-mandate beginning in 2030.
SO WHAT
Regulation is not simply creating SAF demand — it is actively requiring diversification beyond HEFA, compressing the window during which lipid-based HEFA can satisfy full mandate compliance.
NOW WHAT
Producers serving UK and EU markets need a credible pathway diversification timeline, not simply a plan to scale existing HEFA capacity.
Signal 5
FINDING
IATA's own assessment identifies HEFA as the only currently mature SAF route while projecting oil-based HEFA at only slightly above 15% of 2050 SAF production potential — with e-SAF expected to represent the largest single pathway contribution in IATA's long-run assessment.
SO WHAT
The industry's own authoritative body confirms that HEFA is a bridge, not a destination — and the bridge is shorter than current capacity investment patterns imply.
NOW WHAT
Capital allocation decisions made in 2026 and 2027 will determine whether an organisation is positioned for the HEFA era or the post-HEFA era — the two require materially different feedstock and technology strategies.
2. Macro Context & Strategic Drivers
Direct Answer — Why Is SAF Feedstock a Strategic Issue in 2026? SAF feedstock has become a strategic issue in 2026 because binding regulatory frameworks — led by ReFuelEU Aviation and the UK SAF Mandate — are creating guaranteed demand obligations before the diversified supply system has reached commercial maturity. HEFA's dependence on waste lipids means that meeting mandated SAF volumes requires either securing a contested feedstock pool or investing in commercially less mature pathways. The constraint is not biomass in aggregate but qualifying, mobilisable, and economically competitive feedstock delivered at the point of conversion.
2.1 The SAF Market Has Entered the Mandate-Driven Phase
Aviation decarbonisation moved from voluntary corporate commitments to binding regulatory obligations across multiple major markets between 2025 and 2026. The clearest articulation of that shift is Regulation (EU) 2023/2405 — ReFuelEU Aviation, which requires all fuel suppliers to EU airports to blend increasing proportions of SAF: 2% from 2025, 6% from 2030, 20% from 2035, and 70% from 2050. The regulation also establishes a synthetic-fuels sub-target from 2030, signalling that non-lipid SAF pathways are not a distant aspiration but a near-term regulatory requirement.
The UK's position is in some respects more demanding. The UK SAF Mandate — which began in 2025 at 2% — rises to 10% by 2030 and 22% by 2040, while the Sustainable Aviation Fuel Act 2026 provides the statutory framework for revenue certainty mechanisms intended to accelerate UK investment. Critically, the UK mandate explicitly constrains HEFA's eligible share: HEFA can satisfy 100% of the obligation initially, falling to 71% by 2030 and 35% by 2040. The UK's Power-to-Liquid obligation — beginning at 0.2% in 2028 and reaching 3.5% in 2040 — is among the clearest regulatory signals anywhere that non-biological feedstocks must become part of the commercial SAF supply chain within this decade.
For an exploration of the compliance dynamics and procurement costs associated with ReFuelEU, see GFJ's dedicated analysis: ReFuelEU Aviation 2026–2030: SAF Supply, Procurement Costs and the 6% Mandate Challenge.
2.2 Why HEFA Became the Dominant Commercial Pathway
HEFA's dominance in the current SAF market is not accidental. The pathway reached commercial maturity first because it could be retrofitted onto existing hydroprocessing infrastructure already operating at scale in the renewable fuels industry. Feedstock handling, pretreatment chemistry, hydrogenation processes, and product certification were all well understood. IATA confirms that HEFA remains the most commercially mature SAF route available today.
That maturity advantage, however, carries a structural liability: HEFA's feedstock requirement is both specific and contested. The pathway is commercially ready; the feedstock base it relies on is not elastic. An ICAO-hosted Boeing/ICF assessment projected HEFA global SAF production capacity at approximately 18.1 million tonnes by 2030 against expected demand of around 15.5 million tonnes — a narrow surplus that disappears when longer-term demand trajectories and the ~24 Mt projected supply gap by 2035 are considered.
These are Boeing/ICF industry estimates presented through ICAO and should be read as indicative market assessments rather than official ICAO or IEA forecasts, but the directional conclusion — that the buffer between HEFA capacity and feedstock-constrained supply tightens materially after 2030 — is well supported by independent evidence.
2.3 The Global Feedstock Paradox
The apparent contradiction at the centre of the SAF feedstock debate is that biomass resources are simultaneously abundant in aggregate and inadequate at the project level. IATA's 2025 Global Feedstock Assessment identifies substantial global sustainable biomass potential, while also showing that after competing uses and sustainability eligibility are applied, the pool available to SAF narrows substantially. Oil-based HEFA is projected to account for only slightly above 15% of 2050 SAF production potential under IATA's core assessment, meaning that the diversification trajectory is not a distant policy ambition but is embedded in the industry's own analytical base cases.
The US Department of Energy has documented the same structural constraint from a supply-capacity perspective: projected yellow-grease supply in the United States could satisfy only a small proportion of projected aviation fuel demand even under favourable collection assumptions. The IEA warned as early as 2022 that biofuel producers — including biojet producers — faced a feedstock supply crunch across the 2022–2027 period. These are not outlier predictions. They are consistent findings from the most credible institutional sources in energy analysis.
2.4 The Four Forces Reshaping SAF Feedstock Economics
Four structural forces are simultaneously compressing the SAF feedstock market.
First, rising mandated SAF volumes are creating demand obligations that outpace the rate at which qualifying lipid feedstock supply can be mobilised.
Second, renewable diesel demand — which draws on the same UCO and animal fat pool — is expanding in parallel, creating direct price and volume competition for the same carbon.
Third, sustainability restrictions are progressively narrowing which feedstocks qualify for CORSIA, ReFuelEU, and UK mandate compliance, eliminating some apparent supply.
Fourth, alternative SAF pathways — Alcohol-to-Jet, Fischer-Tropsch, and Power-to-Liquid — are commercially less mature today, meaning the feedstock diversification that the market structurally requires cannot simply be purchased off the shelf.
For GFJ's broader analysis of where green hydrogen and e-fuel pathways fit within the decarbonisation economy, see: Green Molecules Economy 2035: Where Green Hydrogen, Ammonia, Methanol and SAF Win the Industrial Energy Transition.
3. Global SAF Feedstock Reality Check
Direct Answer — Is HEFA Running Out of Feedstock? HEFA is not expected to disappear as a commercial pathway, but its scalable growth is constrained by the availability, quality, sustainability, and economics of qualifying lipid feedstocks. The strategic issue is not the absolute depletion of waste oils and fats — it is the mismatch between the rate at which HEFA capacity is being built and the rate at which qualifying feedstock can be mobilised to run it. Broader biomass resources can support Alcohol-to-Jet, Fischer-Tropsch, and Power-to-Liquid pathways, making the question a pathway diversification decision rather than a simple feedstock scarcity problem.
3.1 The GFJ SAF Feedstock Reality Ladder
The most important analytical distinction in the SAF feedstock debate is between theoretical resource and commercially mobilisable supply. Public datasets routinely report headline biomass volumes that bear little relationship to the feedstock quantity that can reach a SAF refinery as certified, convertible material. The GFJ SAF Feedstock Reality Ladder maps the sequential reduction that occurs at each stage of the supply chain:
Theoretical → Recoverable → Collectable → Sustainable → CORSIA / Market Eligible → Contracted → Delivered → Convertible to SAF
Every rung of that ladder reduces the usable pool. A country may report hundreds of millions of tonnes of agricultural biomass in policy documents. A project developer operating in that country must apply collection logistics, competing use deductions, sustainability certification requirements, and buyer eligibility criteria before the addressable feedstock volume becomes a project-level supply figure.
These reductions are substantial and rarely made explicit in public market commentary. The research for this report found no sufficiently robust public dataset that provides a globally consistent accounting of SAF-accessible feedstock after all competing uses and eligibility criteria are applied simultaneously — and that absence is itself the central intelligence gap the market faces.
3.2 Feedstock-by-Feedstock Assessment
The following matrix assesses the major SAF feedstock categories across seven strategic dimensions. Read alongside the GFJ Biofuels & Feedstocks Intelligence Hub for supplementary analysis.
Feedstock | Availability | Cross-Sector Competition | Sustainability Risk | Best Pathway | 2035 Scalability |
Used Cooking Oil (UCO) | Limited — collection-constrained; EU importing 69% of SAF supply | Very High — renewable diesel, biodiesel, oleochemicals | High — fraud/provenance risk; eligibility scrutiny rising | HEFA | Low — ceiling driven by foodservice volumes |
Animal Fats / Tallow | Moderate — tied to livestock volumes | High — oleochemicals, soap, biodiesel | Medium — category distinctions matter by market | HEFA | Low-to-Moderate — livestock ceiling |
Vegetable Oils (virgin) | Theoretically large — eligibility severely constrains qualifying volume | Very High — food, bioenergy, chemicals | Very High — ILUC criteria exclude most virgin oil | HEFA (where eligible) | Very Low — eligibility wall |
Agricultural Residues | High theoretical; collectability limits practical supply | Medium — biomass power, biogas | Medium — soil-health constraints | FT, ATJ | Moderate-to-High — policy support improving |
Municipal Solid Waste (MSW) | Large theoretical — practical varies by infrastructure | Medium — recycling, energy recovery | Medium — non-biogenic fraction excluded | FT, gasification | Moderate — infrastructure-dependent |
Forestry Residues | Large in North America, Nordics; bioenergy demand limits access | High — biomass power, pellets, pulp | Medium — FSC/PEFC certification required | FT | Moderate — geography-dependent |
Ethanol / Alcohol | Large — existing commodity market | Medium — fuel blending, industrial | Low-to-Medium — crop ILUC risk; waste ethanol better | ATJ | High — broadest carbon base |
Renewable H₂ + CO₂ | Theoretically unlimited; constrained by H₂ cost and CO₂ sourcing | Low in 2026 — growing | Low — fully synthetic, GHG favourable | Power-to-Liquid | High by 2035 — cost-dependent |
3.3 The 2030–2035 HEFA Ceiling
The concept of a HEFA ceiling is more precise than it is typically presented. It does not mean that HEFA refineries will run empty or that lipid feedstocks will disappear. It means that the economics of securing incremental qualifying feedstock at competitive prices will become progressively more difficult as demand outpaces mobilisable supply. The ICAO-hosted Boeing/ICF assessment projects a supply gap of approximately ~24 million tonnes by 2035. IATA's long-run assessment locates oil-based HEFA at only slightly above 15% of 2050 SAF production potential — a dramatic reduction from its current near-total dominance. That trajectory is not the result of technology failure. It is the predictable consequence of expanding SAF demand against a feedstock category that cannot scale proportionally with it.
The practical test for any announced HEFA project in 2026 or 2027 is therefore not whether the conversion technology is viable — it demonstrably is — but whether the feedstock contract portfolio backing the project is deep, diversified, and certifiable through the full project life. A HEFA capacity announcement without a credible long-term feedstock plan is a capacity announcement with a concealed supply risk.
4. Global Regional Feedstock & Policy Map
Direct Answer — Which Regions Are Likely to Become Important SAF Feedstock Hubs? North America has the broadest biomass resource base and the largest existing biofuel infrastructure, but also one of the world's most competitive alternative renewable-fuel markets. Europe is a strong SAF demand market but relies heavily on imported feedstock and SAF. India and Southeast Asia — particularly Indonesia and Malaysia — hold large agricultural residue and waste-oil resource bases while developing domestic SAF demand signals. Feedstock availability and exportable supply are distinct: proximity to refining infrastructure, collection systems, and certification frameworks determines whether a resource becomes a trading commodity.
4.1 North America
The United States operates the world's most developed SAF production ecosystem outside Europe, anchored by the SAF Grand Challenge — a multi-agency initiative targeting 3 billion gallons per year of domestic SAF production by 2030 and 35 billion gallons per year by 2050, the latter figure equivalent to projected full domestic aviation fuel demand. The US approach combines the Renewable Fuel Standard's pathway-based credit system with direct federal financing support — exemplified by the Department of Energy's $1.67 billion loan guarantee to Montana Renewables in January 2025.
The US has enormous theoretical biomass resources. NREL's regional analysis, however, explicitly identifies feedstock price and incentive structures as the largest SAF cost drivers, and warns that available feedstocks may instead be directed toward renewable diesel and chemicals where product yields are higher and market structures are more established. The strategic tension in the US SAF market is between the scale of its resource base and the strength of competing demand from a mature, policy-supported renewable fuels industry. For analysis of how US and global capital is allocating across clean energy platforms, see: New Energy M&A Playbook 2026–2027: Where Capital Is Moving.
4.2 EU and United Kingdom
Europe represents the most consequential demand-side regulatory market for global SAF feedstocks. The EU's ReFuelEU Aviation mandate — 2% in 2025, 6% in 2030, 20% in 2035, 70% in 2050 — creates a guaranteed, escalating demand signal that no other jurisdiction has matched at comparable scale. The European Commission's Renewable and Low-Carbon Fuels Value Chain Industrial Alliance, in its February 2026 general assembly, identified Europe's opportunity to position itself as a global SAF deployment leader, while acknowledging the supply-side constraints that make that ambition contingent on feedstock mobilisation beyond the continent's borders.
The EU's 2024 SAF data — 81% from UCO, 69% from outside the EU, 38% of non-EU origin attributed to China — demonstrate that the mandate is already reshaping global feedstock trade flows rather than simply stimulating domestic European supply. The UK's HEFA eligibility limits add a further structural layer: from 2030, UK SAF producers cannot rely on HEFA to satisfy the full mandate obligation, regardless of feedstock access.
4.3 China
China occupies a unique strategic position: it is simultaneously a major supplier of SAF and SAF feedstocks to the European market and a developing domestic SAF market. The NDRC and CAAC launched China's SAF application pilot in September 2024, initially covering Air China, China Eastern, China Southern, and four airports. By August 2025, CAAC reported more than 120,000 pilot flight operations, with domestically produced SAF demonstrating safety and airworthiness under Chinese standards.
No authoritative source confirmed a nationwide Chinese SAF blending mandate equivalent to ReFuelEU or the UK SAF Mandate as of 17 August 2026. China's SAF market is developing through controlled pilot and policy construction phases. Its strategic significance lies in its dual role: a feedstock and SAF exporter to Europe today, and a potential major domestic SAF demand market as its own regulatory framework matures.
4.4 Southeast Asia
Singapore has implemented one of the most architecturally sophisticated SAF procurement frameworks of any jurisdiction of its size. The Civil Aviation Authority of Singapore's framework targets 1% SAF initially, rising to 3–5% by 2030, with a centralised SAF procurement body (SAFCo) aggregating airline demand and procuring through competitive tenders against international sustainability standards. The SAF levy — which applies to flights departing Singapore — provides a dedicated financing mechanism and addresses the offtake aggregation challenge that makes project financing difficult for individual SAF producers.
Across ASEAN more broadly, the ASEAN Centre for Energy has explicitly identified feedstock limitations and policy disparities as the primary reasons for the region's SAF production gap. Indonesia and Malaysia hold significant agricultural residue and palm waste resources, but sustainability eligibility questions around palm-derived feedstocks — particularly indirect land-use change risk — complicate their route to certified SAF supply.
5. India-Specific Analysis
Direct Answer — Why Is India Strategically Important for SAF Feedstock? India combines significant biomass resources and agricultural residues with emerging SAF demand targets and active refinery investment in non-lipid pathways. The government's indicative blending targets — 1% in 2027, 2% in 2028, 5% in 2030 — are backed by the April 2026 ATF Control Order amendment that operationalised India's SAF market framework. The stated biomass availability of 750+ million tonnes should not be interpreted as commercially mobilisable feedstock: collection gaps and certification requirements reduce the practical pool substantially. India's most strategically significant development is IndianOil's 86.8 kt/year Alcohol-to-Jet project at Panipat, developed with LanzaJet.
India's indicative SAF blending roadmap — 1% for international flights in 2027, 2% in 2028, 5% in 2030 — was made operationally credible on 23 April 2026, when India amended the ATF (Regulation of Marketing) Order, 2001 to bring SAF-blended aviation turbine fuel within the existing regulatory framework, explicitly recognising SAF co-processing and SAF-ATF blends under Indian standards. That amendment moves India from aspirational target-setting toward operational market infrastructure — a critical transition for investment-grade SAF project development.
"SAF is a practical and immediate solution to decarbonize the aviation sector."
— Shri Ram Mohan Naidu, Union Minister for Civil Aviation, Government of India. Press Information Bureau press release, 3 September 2025.
5.1 India's Feedstock Opportunity — and the Collection Problem
India's policy documents cite 750+ million tonnes of biomass availability and approximately 230 million tonnes of surplus agricultural residue as evidence of the country's feedstock resource base. These figures are accurate as theoretical resource estimates. They are not equivalent to commercially mobilisable SAF feedstock. The distance between the two is measured in collection infrastructure, moisture and quality standards, competing uses — including biomass energy and animal feed — CORSIA eligibility requirements, and the certification and traceability systems that international buyers require before procurement.
India's civil aviation ministry held a high-level SAF preparedness meeting in July 2026 specifically to review production capacity, certification, supply chains, and commissioning timelines for domestic SAF producers targeting 2027 supply readiness — a signal that the government recognises the gap between resource availability and operational supply. Used cooking oil collection is a further feedstock priority. India's foodservice volume is large, but organised UCO collection infrastructure is at an earlier development stage than in Europe or Japan, where collection systems are more mature.
For context on India's broader carbon market and industrial policy environment, which will interact with SAF feedstock economics, see: Indian Carbon Market 2026: The New Industrial Operating System.
5.2 IndianOil's ATJ Strategy — A Pathway Diversification Case
IndianOil's commercial-scale SAF project at the Panipat refinery is the most strategically significant SAF feedstock development in India and one of the most instructive globally. The facility targets 86.8 kt/year of SAF production through the Alcohol-to-Jet pathway, using ethanol as feedstock and developed in partnership with LanzaJet. IndianOil is also pursuing separate SAF co-processing development at the same site — a multi-pathway approach within a single refinery complex.
The feedstock logic driving IndianOil's ATJ decision is direct: India's ethanol supply base — built through the government's ethanol blending programme and domestic agricultural capacity — provides a feedstock foundation that is not competing with renewable diesel at the same intensity as UCO and animal fats. Ethanol-to-SAF accesses the country's agricultural carbon base without requiring the waste-oil collection infrastructure that European HEFA producers depend upon. IndianOil's approach demonstrates a commercially replicable model for any emerging-market refiner that has ethanol supply chains but limited access to competitively priced waste lipids.
The IEA has separately assessed India's bioenergy potential, noting the country's substantial agricultural biomass base while emphasising the infrastructure and policy requirements needed to translate that resource into productive commercial supply. India's SAF trajectory will be watched closely by global feedstock traders, airline procurement teams, and project financiers as the 2027 supply target approaches.
6. Operational & Technical Deep-Dive
Direct Answer — Why Is Feedstock Cost So Important to HEFA SAF Economics? In an NREL/DOE-linked techno-economic benchmark for a US regional SAF project, feedstock accounted for approximately 70% of HEFA minimum jet selling price — meaning that relatively small changes in feedstock cost produce material changes in the economics of the entire pathway. A reduction of $0.20 per kilogram in feedstock price reduces the MJSP by approximately $0.77/GGE. Conversely, transportation assumptions add approximately $0.23/GGE to cost. These are techno-economic benchmarks, not 2026 global market quotations, but they illustrate why feedstock procurement strategy is inseparable from SAF project economics.
6.1 HEFA: The Incumbent
HEFA converts oils, fats, and greases through a hydroprocessing reaction — hydrogenation of the triglyceride feedstock followed by hydrodeoxygenation and isomerisation to produce a drop-in jet fuel. The process is well understood, can be adapted from existing hydrotreating infrastructure, and produces a high-quality, ASTM-certified product with conversion yields significantly higher than alternative bio-pathways: the NREL/DOE-linked analysis at Chicago O'Hare benchmarks HEFA yield at approximately 247 GGE per dry ton of feedstock, compared to approximately 65 GGE/dry ton for Fischer-Tropsch and approximately 46 GGE/dry ton for Alcohol-to-Jet.
The benchmark's economic findings are worth stating precisely. At a 100-mile feedstock collection radius: feedstock represents approximately 70% of MJSP; a $1/gallon renewable-fuel incentive can reduce MJSP to approximately $2.19/GGE; reducing feedstock price by $0.20/kg reduces MJSP by approximately $0.77/GGE, to approximately $2.43/GGE; and including assumed feedstock transport increases MJSP by approximately $0.23/GGE, to approximately $3.43/GGE. These figures reflect a specific US regional scenario and should not be transposed directly to other geographies, but the structural point — that feedstock is the dominant variable in HEFA economics — is consistent across multiple independent analyses.
6.2 Alcohol-to-Jet
The Alcohol-to-Jet pathway converts ethanol or other alcohols into jet fuel through dehydration, oligomerisation, and hydrogenation. Its strategic advantage over HEFA is access to a significantly broader feedstock base: crop ethanol, cellulosic ethanol, and waste-stream ethanol all qualify, meaning ATJ is not constrained to the same lipid supply pool. The NREL/DOE benchmark finds ATJ MJSP of approximately $2.84/GGE with a $1/gallon incentive. A $20/dry-ton reduction in feedstock price reduces MJSP by approximately $0.57/GGE, to approximately $3.35/GGE. Capital expenditure sensitivity is material: a ±25% change in total capital investment moves MJSP by approximately ±$0.41/GGE. IndianOil's Panipat project demonstrates that ATJ is commercially deployable at scale in an emerging-market context today.
6.3 Fischer-Tropsch
Fischer-Tropsch converts a synthesis gas (syngas) — derived from gasification of biomass, MSW, or agricultural residues — into a range of liquid hydrocarbons including jet fuel. The NREL/DOE benchmark shows FT having the lowest MJSP of the three pathways studied, but with a materially different cost structure: capital costs represent approximately 42% of MJSP, with feedstock at approximately 54%. FT's capital intensity is its primary commercial barrier — the technology requires large-scale investment to achieve competitive unit economics, and project financing for first-of-a-kind commercial FT-SAF facilities has been challenging in most markets. Its feedstock advantage is significant: woody biomass, forestry residues, and MSW access supply pools not contested by renewable diesel.
6.4 Power-to-Liquid and the Synthetic Carbon Pathway
Power-to-Liquid SAF — produced from green hydrogen and a CO₂ source through Fischer-Tropsch or methanol synthesis — is the only SAF pathway genuinely unconstrained by biomass availability. Its feedstock is renewable electricity, water, and atmospheric or point-source CO₂. IATA's long-run assessment identifies e-SAF as the largest single pathway contribution to 2050 SAF production potential in its core forecast — overtaking oil-based HEFA, which is projected at only slightly above 15% of the long-run mix. The EU's 2030 synthetic-fuel sub-mandate under ReFuelEU and the UK's 0.2% PtL obligation from 2028 provide the first regulatory demand signals for this pathway.
PtL's commercial development is currently constrained by the cost of green hydrogen and the scalability of electrolyser deployment.
For a detailed assessment of hydrogen cost trajectories, see: Green Hydrogen Cost Economics 2026: The Real Path to Price Parity.
The same renewable electricity and electrolyser capacity that could support green ammonia or green methanol production competes for allocation with e-SAF: Green Ammonia Exports 2027: Why India and China Are the Only Verified Leaders.
For corporate power procurement context relevant to PtL project economics, see: Corporate PPA 2027: How Companies Are Rebuilding Electricity Procurement for Cost, Reliability, and Net-Zero.
The pathway comparison table below summarises the key strategic differences:
Factor | HEFA | Fischer-Tropsch | Alcohol-to-Jet | Power-to-Liquid |
Commercial Maturity | Highest | Lower | Developing | Early commercial |
Main Feedstock | Oils/fats/greases | Woody biomass, MSW, residues | Ethanol, crop & cellulosic | Renewable electricity + CO₂ |
Yield (GGE/dry ton) | ~247 | ~65 | ~46 | N/A — electricity-based |
Feedstock % of MJSP | ~70% | ~54% | Significant | Electricity cost dominant |
Capital % of MJSP | Lower | ~42% | Material | Very high |
Primary Constraint | Lipid supply ceiling | CAPEX + project finance | Technology scale-up, ethanol cost | Green H₂ cost, CO₂ access |
2035 Scalability | Constrained | Moderate | High | High — cost-dependent |
7. Named Company Case Studies
Direct Answer — Which Companies Illustrate the SAF Feedstock Transition? Neste demonstrates that global HEFA scale amplifies, rather than resolves, feedstock exposure. IndianOil demonstrates that pathway diversification into Alcohol-to-Jet is commercially viable in an emerging-market context. Montana Renewables shows how policy-backed capital can unlock HEFA capacity at refinery scale without resolving the underlying feedstock constraint. China Eastern illustrates how domestic SAF market development and international mandate exposure are becoming simultaneously operative for Asian carriers — and how the feedstock question follows demand into new geographies.
7.1 Neste — HEFA at Global Scale
Neste's position as the world's largest SAF producer makes it the most instructive case study for the structural limits of the HEFA model. The company's 2025 Green Finance Report (published 4 March 2026) confirms global SAF production capability of 2.2 million tonnes per year, with Rotterdam able to produce up to 500,000 tonnes/year of SAF and Singapore carrying an option to produce up to 1 Mt/year.
The Rotterdam expansion illustrates both the ambition and the structural constraints of HEFA scaling. Its investment estimate rose from €1.9 billion to €2.5 billion, and commercial operation was moved from 2026 to 2027 — not as a project-execution failure but as a reflection of the feedstock-security requirements that large-scale HEFA capacity demands. Neste itself has simultaneously expanded its feedstock diversification programme, seeking to incorporate a broader range of renewable materials into its production platform.
The strategic lesson Neste provides is clear: scale does not eliminate feedstock exposure. At 2.2 Mt/year of SAF capability, Neste's feedstock procurement is one of the largest single waste-oil buying programmes in the world. That scale creates purchasing power but also creates concentration risk — any sustained disruption to the global UCO trade flow has direct consequences for production economics.
7.2 IndianOil — Pathway Diversification in Practice
IndianOil's commercial-scale SAF development at the Panipat refinery is this report's most instructive case study on pathway diversification strategy. The project targets 86.8 kt/year of SAF through the Alcohol-to-Jet pathway, using ethanol as feedstock, and is developed in partnership with LanzaJet. IndianOil is simultaneously exploring SAF co-processing at the same facility, providing a multi-pathway approach within a single refinery complex.
The feedstock logic driving IndianOil's ATJ decision is direct: India's ethanol supply base provides a feedstock foundation that is not competing with renewable diesel at the same intensity as UCO and animal fats. Ethanol-to-SAF accesses the country's agricultural carbon base without requiring the waste-oil collection infrastructure that European HEFA producers depend upon. IndianOil's approach is a commercially replicable model for any emerging-market refiner that has ethanol supply chains but limited access to competitively priced waste lipids.
7.3 Montana Renewables — Policy-Backed HEFA Expansion
Montana Renewables received a $1.67 billion DOE loan guarantee announced in January 2025, supporting an expansion of the facility's biofuel production from approximately 140 million gallons per year to approximately 315 million gallons per year. The DOE projected that at full capacity, the facility could represent roughly half of North American SAF production and approximately 12% of global SAF supply through 2030. Most of the incremental production is expected to be SAF.
The strategic lesson is the same as Neste's: the loan guarantee secures the capital structure, not the feedstock. Montana Renewables' utilisation rate through 2030 and beyond will depend on its ability to source qualifying lipid feedstocks at competitive delivered costs — in a North American market where the same feedstocks are contested by established renewable diesel producers.
7.4 China Eastern — Demand-Side Dynamics and International Exposure
China Eastern participated in both phases of China's domestic SAF application pilot, operating four SAF-powered commercial flights daily during the first phase. It conducted the first SAF-powered commercial flight involving the domestically produced C919 aircraft. From January 2025, China Eastern's flights departing from EU airports used fuel blended with 2% SAF, reflecting compliance with ReFuelEU's entry-level obligation.
China Eastern's strategic relevance lies in what it reveals structurally: a Chinese carrier with a large domestic network is now simultaneously managing China's domestic SAF pilot programme and complying with the EU's SAF mandate on its European routes. As China's own SAF framework matures, the feedstock and SAF sourcing decisions of carriers like China Eastern will influence global feedstock trade flows — particularly the UCO and agricultural residue supply chains that connect China to European buyers.
8. Friction, Risk & Systemic Bottlenecks
Direct Answer — What Is the Biggest Unresolved SAF Feedstock Problem? The SAF industry lacks a globally consistent and transparent accounting of how much feedstock is actually available — after competing uses, collection constraints, sustainability eligibility, certification requirements, and contracted volumes are simultaneously deducted. Headline biomass resource estimates routinely overstate commercially investable supply. No authoritative public dataset reviewed for this report provides that accounting across all major feedstock categories at a project-relevant level of specificity. That gap is not a research failure — it is the structural intelligence problem that the industry must resolve before project developers can make fully-informed capital allocation decisions.
8.1 The Mobilisation Gap
The distance between a theoretical biomass resource and delivered, certifiable feedstock is the single largest unresolved risk in the SAF market. Every public resource estimate — including the government-cited figures for India's 750+ Mt biomass base and the US DOE's biomass inventory — represents a gross technical potential that has not been adjusted for collection feasibility, competing demand, or certification eligibility. NREL's regional analysis explicitly warns that assumed feedstock availability may be misleading because the same materials can be directed toward higher-yield or better-incentivised competing uses. DOE's assessment of US yellow-grease supply reaches the same conclusion from a domestic capacity perspective: even under favourable collection assumptions, supply falls well short of the volumes that projected aviation fuel demand would require.
8.2 Cross-Sector Feedstock Competition
SAF does not compete exclusively against fossil jet fuel for market share. It competes against renewable diesel, biodiesel, oleochemicals, soap, and a range of bio-based chemical applications for the same waste-lipid feedstocks. Renewable diesel in particular — which uses the same HEFA conversion chemistry as SAF — offers higher product yield from the same feedstock and has benefited from strong policy support in both the US and EU. NREL's analysis identifies the diversion of SAF-qualifying feedstocks to renewable diesel as a direct risk to SAF supply adequacy. That competition is not theoretical: it is expressed daily in the spot market for UCO and animal fats, and its effect on delivered SAF feedstock cost is already embedded in project economics.
8.3 Feedstock Quality Risk
Quantity of feedstock is an insufficient condition for project viability. The quality, composition, and consistency of lipid feedstocks directly affect HEFA conversion efficiency and pretreatment costs. Feedstocks with higher free fatty acid content, moisture, or contamination require additional processing. Heterogeneous UCO supply — which varies in composition by source geography, foodservice type, and collection method — creates quality management challenges at scale. For Fischer-Tropsch projects, the calorific value, moisture content, and ash content of biomass feedstocks are direct determinants of syngas yield and plant performance.
8.4 Sustainability and Eligibility Risk
A feedstock being technically available does not mean it is eligible for all SAF markets. CORSIA maintains a defined list of recognised SAF feedstocks and applies lifecycle emissions criteria that vary by conversion pathway. ReFuelEU's sustainability criteria align with the EU's Renewable Energy Directive framework, which applies indirect land-use change risk assessments and supply-chain traceability requirements. The UK SAF Mandate applies its own eligibility framework. These regulatory systems are not identical — a feedstock qualifying in one jurisdiction may not qualify in another, adding a layered eligibility management requirement that raises operational complexity and cost for producers targeting multiple mandate markets.
8.5 Geographic Mismatch
The EU's 2024 data provide the clearest example of geographic mismatch at scale: 69% of EU SAF originates outside the Union, with 38% of non-EU supply attributed to China. Europe is funding global feedstock supply chains to meet its own mandate, creating dependency on trade flows subject to geopolitical disruption, export restriction, and competing domestic demand as importing countries develop their own SAF programmes. As India, Singapore, and China mature their own SAF demand frameworks, feedstock and SAF volumes currently flowing to Europe may face competing domestic destinations, tightening supply and raising costs for European buyers.
8.6 The Critical Unresolved Issue: How Much of the World's SAF Feedstock Is Actually Investable?
The research for this report found no sufficiently robust public dataset that simultaneously balances global UCO, tallow, vegetable oils, agricultural residues, MSW, ethanol, and synthetic carbon feedstocks against their competing uses and produces a project-level investable supply figure by region. This is not a minor data gap. It is the central intelligence deficit in the SAF market: project developers are making multi-hundred-million-dollar investment decisions without a transparent, authoritative feedstock accounting that shows how much qualifying supply is actually available after the full ladder of reductions is applied. The absence of that accounting is the market's most consequential unresolved problem — and it is precisely the reason a premium intelligence product covering this topic has genuine institutional value.
8.7 Alternative Pathway Financing Risk
Fischer-Tropsch, Alcohol-to-Jet, and Power-to-Liquid pathways can, in principle, access feedstock pools that are structurally different from — and less constrained than — the lipid supply that HEFA requires. But they introduce technology risk, CAPEX intensity, and commercial maturity challenges that HEFA does not carry. The NREL analysis identifies this directly as the central investment dilemma: HEFA is commercially ready but feedstock-constrained; FT, ATJ, and PtL offer potentially more scalable feedstock bases but are commercially harder to finance in the near term. That is not a paradox that resolves itself — it requires deliberate capital allocation and policy support to bridge.
9. Capital & Investment Implications
Direct Answer — When Should an SAF Producer Diversify Beyond HEFA? Diversification beyond HEFA becomes financially rational when: long-term qualifying lipid supply cannot be secured at defensible delivered cost; competing renewable-fuel demand structurally raises feedstock prices above project-level MJSP thresholds; regulatory frameworks in target markets begin constraining HEFA's eligible share of mandate compliance; or alternative pathway technologies reach sufficient commercial maturity for project financing. The decision is not binary — the optimal position for most large SAF producers through 2030 is a portfolio that maintains HEFA where feedstock is secured and builds ATJ or FT optionality where it is not.
9.1 Reframing the Investment Question
"Which SAF technology wins?" is not the right question for an industrial strategist in 2026. Multiple pathways will coexist through 2035 and beyond — regulatory frameworks in the EU and UK are explicitly designed to ensure that.
The correct question is: which combination of feedstock + conversion pathway + policy market + offtake structure produces defensible economics through 2035 for a specific project in a specific geography?
That question cannot be answered by pathway analysis alone. It requires a simultaneous assessment of feedstock security, regulatory eligibility, capital structure, and commercial offtake.
9.2 Feedstock Security as Project Finance Infrastructure
SAF project finance today sits where renewable energy project finance sat before long-term power purchase agreements became standard: the demand obligation is established, but the supply-side contractual infrastructure needed for lowest-cost financing has not yet been built. Solar and wind projects became bankable at scale when revenue certainty was established through long-term PPAs.
SAF projects face the mirror-image challenge: offtake structures are improving as mandates create guaranteed demand, but feedstock security has not yet reached the contractual depth that project lenders require for longest-tenor financing. Long-term feedstock supply agreements — with price-indexation mechanisms, minimum-volume commitments, quality specifications, and certification guarantees — are the critical missing infrastructure in most SAF project finance structures. Producers who can demonstrate that feedstock security access a materially different tier of capital. For analysis of how energy infrastructure financing structures are evolving, see: New Energy M&A Playbook 2026–2027: Where Capital Is Moving.
9.3 GFJ HEFA Diversification Trigger Framework
The following scorecard identifies the conditions that rationally trigger capital reallocation from pure-HEFA toward diversified or alternative pathway SAF investment:
Trigger Condition | Signal Strength | Strategic Response |
Long-term qualifying lipid supply cannot be contracted at project-level MJSP threshold | Critical | Evaluate ATJ or FT feedstock alternatives immediately |
Renewable diesel competing demand structurally raises UCO/tallow spot price above HEFA break-even | High | Hedge feedstock exposure; initiate ATJ pathway development |
Target market regulation limits HEFA's eligible mandate share below project utilisation requirement | High | Build non-HEFA pathway capacity proportional to ineligible volume |
Feedstock certification or provenance scrutiny raises eligibility risk for contracted supply | Medium-High | Diversify supplier base; invest in traceability infrastructure |
Project location creates structural delivered-feedstock cost disadvantage versus refinery peers | Medium | Reassess feedstock logistics; consider co-location with collection infrastructure |
ATJ or FT alternative pathway technology reaches sufficient commercial maturity for project financing | Medium | Pilot alternative pathway at brownfield site; build track record for future scale |
Policy begins rewarding non-lipid pathways with additional certification credit or incentive | Medium | Accelerate alternative pathway investment; capture early-mover policy premium |
10. Future Scenarios & Forecast 2026–2035
Direct Answer — What Will the SAF Feedstock Landscape Look Like in 2035? By 2035, HEFA will almost certainly remain a significant SAF pathway, but its share of total production will have declined from its current near-total dominance as waste-lipid supply constraints become binding and alternative pathways reach commercial scale. Agricultural and forestry residues, waste-derived feedstocks, ethanol, and eventually synthetic carbon from Power-to-Liquid will represent growing shares. The precise mix depends on feedstock economics, technology deployment rates, and policy evolution — particularly whether the EU's synthetic-fuel sub-mandate and the UK's PtL obligation catalyse sufficient investment in next-generation pathways before the HEFA ceiling becomes economically constraining.
Scenario 1 — HEFA Extension (2026–2030)
HEFA retains dominant market share through 2030 because alternative pathways do not reach commercial scale fast enough to displace it, and feedstock supply — while tight — remains adequate at elevated cost.
Key enabling conditions: strong policy incentives maintaining HEFA economics; continued UCO and tallow supply from Asian and Latin American geographies; project finance remaining available for HEFA at acceptable returns.
Key risk: feedstock cost inflation erodes margins and makes new HEFA projects economically marginal. Strategic implication: secure feedstock contracts immediately, before market tightening drives prices beyond project-level thresholds. Producers entering the HEFA market in 2027 or 2028 without contracted feedstock are taking a structural risk that early movers do not carry.
Scenario 2 — Diversified Bio-SAF (2028–2035)
ATJ and FT pathways reach commercial scale — driven by the UK's HEFA eligibility cap, EU synthetic-fuel requirements, and maturing project finance structures for non-lipid SAF — producing a diversified bio-SAF market in which HEFA remains important but accounts for a meaningfully smaller share of new capacity additions from 2028 onward. Ethanol feedstock — particularly from cellulosic and agricultural-waste sources — grows as the primary alternative carbon base. IndianOil's Panipat development provides a model that other emerging-market refiners can replicate.
Key enabling condition: project finance for ATJ and FT matures sufficiently to replace HEFA capacity growth at competitive IRRs.
Key risk: technology risk and CAPEX intensity delay ATJ/FT scale-up, leaving a supply gap that regulation demands be filled.
Scenario 3 — Synthetic SAF Acceleration (2030–2035)
Power-to-Liquid SAF scales faster than current projections because renewable electricity costs continue declining, electrolyser manufacturing reaches cost targets, and the EU's synthetic-fuel sub-mandate plus the UK's PtL obligation create sufficient demand certainty for project financing. Direct Air Capture and point-source CO₂ become commercially available at scale. Green hydrogen cost reduction becomes the critical variable: each significant reduction in electrolyser capex and renewable electricity LCOE improves e-SAF economics materially.
Key enabling condition: green hydrogen achieves a delivered cost that makes e-SAF competitive with lipid-based feedstocks in HEFA economics by the mid-2030s.
Key risk: CO₂ sourcing infrastructure and electrolyser manufacturing cannot scale as fast as policy demand signals require, leaving PtL at niche volumes through 2035.
See GFJ's analysis of clean power economics for the electricity cost context: Clean Power in 2026: Why Solar + Storage Are Now Beating Coal and Gas.
11. Strategic Recommendations
Direct Answer — What Should SAF Companies Do About Feedstock Risk in 2026? Secure qualifying feedstock contracts before committing to expanded refinery capacity. Diversify feedstock sources across multiple lipid categories and geographies to reduce concentration risk. Build or acquire collection and traceability infrastructure as a strategic asset, not an operating cost. Develop ATJ or FT pathway optionality at existing refinery sites as an insurance position against HEFA feedstock cost inflation. Stress-test project economics against a scenario in which feedstock cost rises 20–30% from today's baseline due to renewable diesel competition and tightening supply. Treat sustainability certification depth as a commercial differentiator, not a compliance overhead.
For Industry
Secure feedstock contracts before announcing capacity expansion. The fundamental error in HEFA project development is treating feedstock procurement as a post-FID activity. Projects that announce capacity first and seek feedstock second are structurally exposed. Long-term supply agreements covering a substantial proportion of nameplate capacity are a prerequisite for rational HEFA investment.
Diversify feedstock categories — UCO, animal fats, tallow — across geographies to avoid single-source concentration. Evaluate vertical integration into collection and aggregation as a means of creating a proprietary cost advantage. Develop ATJ or FT pathway capability at existing refinery sites, treating the investment as optionality insurance against HEFA feedstock inflation. Treat sustainability certification chains as an operational asset — producers who can demonstrate provenance and certification depth will access both a better feedstock price and a more fundable project finance structure.
"We are committed to building the technology and fuel supply that will see greener flying become a reality in a way that protects consumers."
— Mike Kane, Aviation Minister, UK Department for Transport. Government announcement, 3 March 2025.
For Investors
Assess feedstock security before headline SAF capacity in any due diligence process. A project with announced capacity but uncontracted or under-specified feedstock supply carries a risk profile that headline capacity figures do not reflect. Discount projects that rely on theoretical feedstock availability rather than contracted or demonstrably collectible supply. Examine the ratio of contracted to uncontracted feedstock in any HEFA project's supply plan and apply appropriate haircuts to uncontracted volumes.
Evaluate pathway optionality: projects that can shift between feedstock categories or pathways as market conditions evolve carry structurally better risk profiles than single-feedstock, single-pathway facilities. Stress-test feedstock price scenarios — particularly the impact of a sustained 20–30% rise in UCO or animal fat prices on project-level returns. Geographic concentration is a further risk dimension: projects dependent on feedstock from a single source country or region carry supply-chain disruption risk that diversified feedstock portfolios do not.
For Policymakers
SAF mandates create demand certainty. They do not create supply certainty. The most important policy gap in virtually every major SAF market in 2026 is feedstock mobilisation infrastructure — the collection, pre-processing, certification, and logistics systems that convert theoretical resource into delivered, eligible feedstock. Supporting investment in those infrastructure layers is as strategically important as setting blending targets. Develop consistent, internationally interoperable sustainability eligibility frameworks — the current patchwork of CORSIA, ReFuelEU, and UK mandate criteria creates unnecessary compliance complexity that raises costs for producers serving multiple markets.
Avoid creating policy incentives that pit SAF feedstock demand against renewable diesel demand for the same lipid supply. Support alternative pathway commercialisation through long-term investment certainty mechanisms, as the UK's Sustainable Aviation Fuel Act 2026 revenue certainty framework attempts to do. Invest in feedstock mapping and transparency — a publicly available, authoritative accounting of nationally available SAF-eligible feedstock by category, competing use, and collection feasibility would significantly reduce the information cost of SAF project development.
For additional context on the E-Fuels and SAF market, see: E-Fuels & Sustainable Aviation Fuel Intelligence Hub.
For the industrial strategist who is the primary audience of this report, the decisive action in 2026 is not to choose between HEFA and alternative pathways in the abstract — it is to establish the feedstock contract coverage, certification infrastructure, and pathway optionality that will determine whether a SAF position remains commercially viable when the HEFA feedstock ceiling begins to constrain project economics between 2030 and 2035.
12. Executive FAQ
Is HEFA SAF running out of feedstock?
HEFA is not running out of feedstock in an absolute sense — waste oils and fats will continue to exist as long as food processing and livestock industries operate. The strategic problem is that HEFA's scalable growth is constrained by the mobilisable pool of qualifying, sustainable, and economically competitive lipid feedstock. An ICAO-hosted Boeing/ICF assessment projects a global SAF supply gap of approximately ~24 Mt by 2035, driven primarily by HEFA's inability to scale proportionally with mandate-
driven demand growth. The pathway faces a scalability ceiling, not an imminent supply collapse.
What is the biggest constraint on global SAF feedstock supply?
The primary constraint is not the total volume of biomass available globally — it is the quantity of feedstock that is simultaneously sustainable, collection-feasible, certification-eligible, not contracted for competing uses, and economically deliverable to a SAF conversion facility. Public resource estimates consistently overstate commercially mobilisable supply. The US DOE has assessed that projected yellow-grease supply could satisfy only a small proportion of projected aviation fuel demand — illustrating the scale of the mobilisation gap between resource and delivered feedstock.
Which feedstocks are most important for SAF production today?
Used cooking oil and animal fats are the dominant commercial feedstocks for HEFA SAF today. In 2024, 81% of EU SAF was produced from used cooking oil — the clearest available data point on current market composition. These waste lipid streams offer high HEFA yields and established supply chains but are finite in volume, highly contested by renewable diesel demand, and subject to increasing sustainability scrutiny. Ethanol is the primary feedstock for the emerging Alcohol-to-Jet pathway, with broader scalability potential than lipids.
Is renewable diesel competing with SAF for the same feedstock?
Yes. Renewable diesel uses HEFA-equivalent hydroprocessing chemistry and draws on the same UCO and animal fat feedstock pool as SAF. In many market conditions, renewable diesel offers higher product yield from the same feedstock volume and benefits from comparable policy incentives. NREL's regional analysis identifies SAF-feedstock diversion to renewable diesel as a quantified supply-adequacy risk. SAF therefore does not compete only against fossil jet fuel — it competes against the broader renewable fuel market for the same sustainable carbon.
Which SAF pathways can reduce dependence on HEFA feedstocks?
Alcohol-to-Jet accesses ethanol feedstock from agricultural and cellulosic sources, expanding the available carbon base beyond waste lipids. Fischer-Tropsch converts biomass, forestry residues, and municipal solid waste — feedstocks structurally distinct from the lipid pool HEFA requires. Power-to-Liquid uses renewable electricity and CO₂, making it theoretically unconstrained by any biological feedstock. IATA's long-run assessment identifies e-SAF as the largest single pathway contribution to 2050 SAF production potential in its core forecast — overtaking oil-based HEFA, projected at only slightly above 15% of the long-run mix.
Which SAF feedstocks are most scalable through 2030 and 2035?
Agricultural and forestry residues, MSW, and ethanol offer the most scalable feedstock bases through 2030 for bio-pathways, subject to collection infrastructure development. Ethanol is the most commercially proximate feedstock for ATJ scale-up, with IndianOil's 86.8 kt/year Panipat project providing a working reference. Synthetic carbon from Power-to-Liquid becomes increasingly scalable through 2035 as green hydrogen costs decline — with the EU's 2030 synthetic-fuel sub-mandate and UK's PtL obligation from 2028 providing the first regulatory demand signals.
Why is UCO so important to the SAF market today?
Used cooking oil is currently the most accessible qualifying lipid feedstock for HEFA — it has established collection infrastructure in Europe and Asia, high HEFA conversion efficiency, and clear sustainability eligibility under CORSIA and most regional frameworks. Its dominance in EU SAF supply — 81% of 2024 supply — reflects its commercial advantages. Its strategic vulnerability is equally clear: it is a finite stream, 69% of EU supply originates outside Europe, and it is contested by renewable diesel buyers. UCO is the current SAF market's foundation and its primary structural constraint simultaneously.
Should SAF producers invest in HEFA or next-generation pathways?
The answer depends on feedstock access, not pathway preference. Producers with secured, long-term qualifying lipid supply at competitive delivered cost should maintain and optimise their HEFA position through 2030. Producers without that feedstock security should treat HEFA expansion with caution and allocate capital toward ATJ or FT optionality in parallel. No producer building a multi-decade SAF business should plan a single-pathway, single-feedstock strategy for 2035 and beyond — the regulatory and feedstock environment both demand portfolio construction.
13. Legal Disclaimer
This report is provided for informational and strategic research purposes only. It does not constitute investment, legal, regulatory, tax, financial, engineering, or safety-certification advice. Forecasts, scenarios, and projections represent analytical assessments based on publicly available information as of the research cut-off date of 17 August 2026 and may change as technology, policy, commodity prices, project execution, and regulatory frameworks evolve. References to specific companies, projects, or organisations are used for analytical illustration purposes and do not constitute endorsements, recommendations, or assessments of investment suitability. No reliance should be placed on this analysis for commercial, regulatory, or investment decisions without independent professional advice. Full terms at greenfueljournal.com/disclaimers.
14. References & Strategic Sources:
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2. IEA | Renewables 2025 — Renewable Transport | 2025 | https://www.iea.org/reports/renewables-2025/renewable-transp…
3. IEA | Unlocking India's bioenergy potential | 12 February 2025 | https://www.iea.org/commentaries/unlocking-indias-bioenergy-…
4. ICAO | SAF Framework | Current | https://www.icao.int/SAF
5. ICAO / Boeing / ICF | SAF Market Outlook — 2025 Regional Seminar on Environment | 2024 | https://www.icao.int/sites/default/files/EURNAT/Documents/EU…
6. ICAO | CORSIA SAF Feedstocks | Current | https://www.icao.int/CORSIA/feedstocks
7. IATA | Global Feedstock Assessment for SAF Production: Outlook to 2050 | September 2025 | https://www.iata.org/en/publications/economics/reports/globa…
8. US DOE | SAF Grand Challenge Roadmap | 23 September 2022 | https://www.energy.gov/cmei/fuels/articles/saf-grand-challen…
9. US DOE / NREL (Bhatt et al.) | Evaluation of performance variables to accelerate the deployment of sustainable aviation fuels at a regional scale | 2023 | https://afdc.energy.gov/files/u/publication/evaluation_perfo…
10. US EPA | Approved Pathways for Renewable Fuel | Current | https://www.epa.gov/renewable-fuel-standard/approved-pathway…
11. US DOE | DOE Announces $1.67 Billion to Montana Renewables | 10 January 2025 | https://www.energy.gov/edf/articles/doe-announces-167-billio…
12. European Commission | ReFuelEU Aviation — Transport Policy | Current | https://transport.ec.europa.eu/transport-modes/air/environme…
13. EUR-Lex | Regulation (EU) 2023/2405 — ReFuelEU Aviation | Updated 16 April 2026 | https://eur-lex.europa.eu/EN/legal-content/summary/refueleu-…
14. European Commission | Renewable and Low-Carbon Fuels Value Chain Industrial Alliance — 4th General Assembly Highlights Report | 26 February 2026 | https://transport.ec.europa.eu/document/download/9650ac24-12…
15. UK Department for Transport | The SAF Mandate: an essential guide | 19 December 2024 | https://www.gov.uk/government/publications/about-the-saf-man…
16. UK Parliament | Sustainable Aviation Fuel Act 2026 | 2026 | https://www.legislation.gov.uk/ukpga/2026/9
17. UK Department for Transport | SAF supply and industry certainty in an evolving market — Call for Evidence | 16 June 2026 | https://www.gov.uk/government/calls-for-evidence/saf-mandate…
18. CAAC | China Launches Pilot Project for the Application of Sustainable Aviation Fuel | 27 September 2024 | https://www.caac.gov.cn/English/News/202409/t20240927_225510…
19. CAAC | First SAF Technology Innovation and Industrial Development Exchange Conference | 27 August 2025 | https://www.caac.gov.cn/English/News/202508/t20250827_228412…
20. Government of India / PIB | SAF — a practical and immediate solution | 3 September 2025 | https://www.pib.gov.in/PressReleasePage.aspx?PRID=2163273
21. Government of India / PIB | Government Brings SAF-Blended Aviation Fuel Under ATF Control Order | 23 April 2026 | https://www.pib.gov.in/PressReleasePage.aspx?PRID=2255021
22. Government of India / PIB | India SAF Preparedness Meeting | 29 July 2026 | https://www.pib.gov.in/PressReleasePage.aspx?PRID=2291473
23. CAAS | New Sustainable Aviation Fuel Levy | 10 November 2025 | https://www.caas.gov.sg/resources/media-and-publication/news…
24. CAAS | Airline domain sustainability initiatives | Updated 12 May 2026 | https://www.caas.gov.sg/sustainability/airline-domain-sustai…
25. ASEAN Centre for Energy | Workshop on Strategic Renewable Energy Policy for ASEAN Energy Interconnection | 7 July 2025 | https://aseanenergy.org/articles/workshop-on-strategic-renew…
26. Neste | Green Finance Report 2025 | 4 March 2026 | https://www.neste.com/files/pdf/Nf3GEWf8YFsaobDOlMrbX-Neste_…
27. IndianOil | Annual Report 2024–25 — Chairman's Perspective | 2025 | https://iocl.com/uploads/Annual_Report-2024-25/chairmans-per…
28. IndianOil | Annual Report 2024–25 — Manufactured Capital | 2025 | https://iocl.com/uploads/Annual_Report-2024-25/manufactured-…
29. SASAC | China Eastern Expands Sustainable Aviation Fuel to Accelerate Low-Carbon Transformation | 27 June 2025 | https://en.sasac.gov.cn/2025/06/27/c_19511.htm
This report is backed by authoritative research, institutional analysis, industry intelligence, and strategic data sources.
© 2026 Green Fuel Journal / Sekason Research Limited. All rights reserved.
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