Advanced biofuels (SAF, renewable diesel & biomethane)

01Overview and value chain

Markers: [EC: ReFuelEU Aviation & RED III | OECD: Bioenergy | Regulator: EPA (USA), ADEME (France), FERC (USA)]

Advanced biofuels convert waste oils, crops and lignocellulosic residues into drop-in fuels that cut lifecycle CO2 by 50–90% versus fossil equivalents while needing no engine or infrastructure changes. Sustainable aviation fuel (SAF) is the demand spike: global SAF output reached about 1.5 Mt in 2024 — roughly 1.9 billion litres, yet still only 0.53% of jet fuel — and IATA projects demand near 6 Mt in 2025 and 20 Mt by 2030, rising to about 358 Mt by 2050 when SAF is expected to deliver 65% of aviation’s emissions cuts. Three conversion routes dominate: hydroprocessing of fats and oils (HEFA), alcohol-to-jet (ATJ), and anaerobic digestion to biomethane. The synergy is feedstock flexibility plus refinery reuse: the same waste-lipid stream can swing between renewable diesel and SAF as price and mandate demand shift.

Key directions of advanced biofuels:

1. HEFA renewable diesel and SAF (Hydroprocessed Esters & Fatty Acids): waste cooking oil, tallow and vegetable oils hydroprocessed into diesel and jet — the dominant pathway today, with waste-oil routes near 20 gCO2e/MJ.
2. Alcohol-to-jet SAF (Alcohol-to-Jet): ethanol or isobutanol dehydrated, oligomerized and hydrogenated into jet-range paraffins, fully blend-compatible with Jet A-1.
3. Bioethanol as fuel and platform (Bioethanol): corn, sugarcane and cellulosic sugars fermented to ethanol for E15+ blends and as ATJ feedstock.
4. Biomethane and biogas (Biomethane): municipal and agricultural residues digested to biogas, then upgraded to grid-injection renewable natural gas.

Sectoral value chain

[feedstock] ──> [pretreatment] ──> [conversion] ──> [upgrading]
                                  │
                          (H2 + catalysis)
                                  │
                                  ▼
[SAF + diesel + RNG] <─── [certification] <─────┘

Value chain levels

Cross-cutting technologies of the sector:

• HEFA hydroprocessing (HEFA Hydroprocessing): catalytic deoxygenation of fats with hydrogen.
• Alcohol-to-jet catalysis (Alcohol-to-Jet Catalysis): dehydration–oligomerization–hydrogenation of alcohols.
• Carbon capture and sequestration (Carbon Capture & Sequestration): Class VI sequestration cutting pathway carbon intensity.

02US

The US anchors the world’s largest ethanol base and is scaling alcohol-to-jet under the EPA Renewable Fuel Standard and IRA clean-fuel credits.

renewable fuel standard, alcohol-to-jet scale-up, corn ethanol base

• POET: the largest US bioethanol producer with 35 biorefineries; its Shelbyville plant is doubling output from 98 to 193 million gallons per year (200 million dollar build, completion Q4 2027), and Iowa alone produced 4.6 billion gallons of ethanol in 2024.
• LanzaJet: Freedom Pines Fuels in Soperton, Georgia — the world’s first commercial-scale ethanol-to-SAF plant, operational since November 2025 on over 300 million dollars of investment.
• Gevo: the ATJ-30 project at Richardton, North Dakota pairs ethanol-to-jet with Class VI carbon sequestration, backed by a portfolio of more than 550 patents.

03CN

China decarbonizes aviation through waste-oil HEFA plants and CAAC airworthiness certification, with national SAF pilots running at four airports since 2023.

waste-oil HEFA SAF, CAAC certification, airport pilots

• EcoCeres: its Zhangjiagang plant makes HEFA-SPK from waste and residue feedstock with up to 90% lower lifecycle GHG, and in September 2025 became the 5th Chinese producer to win a CAAC CTSOA, anchoring the “Spark Plan” pilot fuelling commercial flights at Chengdu.
• Jiaao Enprotech (603822.SH): its Lianyungang biojet project runs at 500,000 tonnes per year from waste oils, with BP as a strategic investor and ISCC plus CAAC certification; it shipped China’s first biojet export of about 13,400 tonnes in May 2025.
• National SAF pilots: the CAAC and NDRC have run staged SAF trials across major airports, building toward routine blending.

04EU

The EU drives demand with the binding ReFuelEU Aviation mandate and leads on HEFA capacity and biomethane biorefineries.

ReFuelEU mandate, HEFA leadership, biomethane biorefineries

• Neste: the world’s largest SAF producer, with about 3.3 Mt/yr of renewable capacity across Singapore, Rotterdam and Porvoo and roughly 1.5 Mt of SAF in 2025, targeting 2.2 Mt/yr of SAF and 6.8 Mt/yr of renewables by 2027.
• Verbio: operates biomethane, biodiesel and bioethanol biorefineries with about 1,400 employees, adding renewable chemicals via ethenolysis and a US ethanol/biomethane plant in Nevada.
• ReFuelEU Aviation: mandates a rising SAF share from 2025 toward 6% by 2030, with RED III requiring at least 50% GHG savings and barring food-crop feedstock.

05Leading companies and research institutes

06Tech stack and innovations

The stack rests on three conversion platforms, each matched to a feedstock class.

1. HEFA hydroprocessing (HEFA Hydroprocessing):
   • waste fats and oils plus hydrogen yield renewable diesel and SAF at 50–90% lower lifecycle CO2.
   • Neste co-processes SAF in existing refineries, reaching about 3.3 Mt/yr of renewable capacity.
2. Alcohol-to-jet catalysis (Alcohol-to-Jet):
   • ethanol or isobutanol is dehydrated, oligomerized and hydrogenated into Jet A-1-compatible fuel.
   • LanzaJet’s Freedom Pines became the first commercial ethanol-to-SAF plant in 2025; Praj licenses the Axens Jetanol pathway.
3. Anaerobic digestion and biomethane (Biomethane):
   • municipal and agricultural residues are digested to biogas, then upgraded to grid-injection RNG.
   • Verbio runs circular biomethane biorefineries on regional biomass.

07Value chains and production pipelines

Industrial pipeline of HEFA SAF production (ASTM D7566)

┌───────────────────────────┐      ┌───────────────────────────┐
│ 1. Feedstock collection   │ ───> │ 2. Pretreatment           │
└───────────────────────────┘      └───────────────────────────┘
                                                 │
                                                 ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 4. Hydrocracking          │ <─── │ 3. Hydrotreating (HDO)    │
└───────────────────────────┘      └───────────────────────────┘
              │
              ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 5. Fractionation          │ ───> │ 6. Certification & dispatch│
└───────────────────────────┘      └───────────────────────────┘

Stage 1: Feedstock collection

Used cooking oil, tallow and crop residues are aggregated and quality-checked for moisture, free fatty acids and contaminants.

Stage 2: Pretreatment

Degumming, bleaching and acid removal condition the lipids, protecting downstream catalysts from poisoning.

Stage 3: Hydrotreating (HDO)

Catalytic hydrodeoxygenation with hydrogen strips oxygen from the fats, producing straight-chain paraffins.

Stage 4: Hydrocracking

Cracking and isomerization break and branch the paraffins into jet-range and diesel-range molecules.

Stage 5: Fractionation

Distillation splits the stream into SAF and renewable diesel cuts, balanced to demand and price.

Stage 6: Certification & dispatch

Blendstock is tested to ASTM D7566 and ISCC, blended to spec, and dispatched to airlines and fleets.