Operational playbook: Scaling Sustainable aviation & shipping from pilot to rollout

Global aviation contributes roughly 2.5% of energy-related CO₂ emissions, while international shipping adds another 2.8%, yet both sectors remain among the hardest to decarbonize. According to the International Air Transport Association (IATA), sustainable aviation fuel (SAF) accounted for just 0.53% of total jet fuel consumption in 2025, despite $17 billion in announced SAF production capacity. The gap between pilot-stage commitments and full-scale deployment is where most decarbonization programs stall. This playbook offers a phase-by-phase framework for moving sustainable aviation and shipping initiatives from early trials to operational rollout, drawing on lessons from leading airlines, shipping lines, and fuel producers that have crossed the valley of death between demonstration and commercial-scale impact.

Why It Matters

Aviation and maritime shipping together move 90% of global trade by volume and connect 4.5 billion passengers per year. Without credible decarbonization pathways, both sectors face escalating regulatory costs: the EU Emissions Trading System (ETS) now covers intra-European flights, and the International Maritime Organization (IMO) revised its GHG strategy in 2023 to target net-zero emissions by or around 2050. FuelEU Maritime mandates a 2% greenhouse gas intensity reduction for ships calling at EU ports starting in 2025, ramping to 80% by 2050. Airlines face the EU's ReFuelEU Aviation mandate requiring 2% SAF blending by 2025 and 70% by 2050.

For sustainability leads managing decarbonization programs, the challenge is not finding pilot projects: it is building the operational infrastructure, commercial agreements, and organizational capabilities to scale those pilots into system-wide change. Most organizations that fail at scaling do so not because of technology limitations, but because of procurement bottlenecks, unclear internal ownership, misaligned incentive structures, and an inability to integrate new fuel pathways into legacy logistics and supply chains.

Key Concepts

Sustainable Aviation Fuel (SAF): Drop-in fuels produced from waste feedstocks (used cooking oil, municipal solid waste, agricultural residues) or via power-to-liquid synthesis using green hydrogen and captured CO₂. SAF can reduce lifecycle emissions by 50% to 80% compared to conventional jet fuel, depending on the feedstock pathway.

Alternative Maritime Fuels: Green methanol, ammonia, LNG (as a transitional fuel), and hydrogen are the leading contenders for shipping decarbonization. Maersk has ordered 25 methanol-capable vessels, making green methanol the most commercially advanced option for container shipping.

Book-and-Claim: An accounting mechanism where a buyer purchases SAF credits without physically receiving the fuel. This approach decouples the point of production from the point of consumption, enabling airlines to claim emissions reductions even when SAF is injected at a different airport. The Roundtable on Sustainable Biomaterials (RSB) and the International Sustainability and Carbon Certification (ISCC) both provide chain-of-custody standards.

Operational Energy Efficiency: Measures such as hull coatings, air lubrication, route optimization, weather routing, and slow steaming that reduce fuel consumption without changing fuel type. McKinsey estimates that operational efficiency improvements can cut shipping emissions by 5% to 15% before any fuel switching occurs.

Carbon Insetting vs. Offsetting: Insetting invests in emissions reductions within the company's own value chain (such as purchasing SAF), while offsetting involves buying credits from unrelated projects. CORSIA (the Carbon Offsetting and Reduction Scheme for International Aviation) allows both approaches, but investors and regulators increasingly favor insetting.

What's Working

SAF offtake agreements are locking in demand signals. United Airlines signed the largest publicly disclosed SAF purchase agreement in aviation history: a $1.5 billion deal with Archer-Daniels-Midland (ADM) for SAF produced from used cooking oil and animal fats via HEFA (hydroprocessed esters and fatty acids) pathways. Delta Air Lines committed to purchasing 385 million gallons of SAF over 10 years from Gevo, with deliveries beginning in 2026 from Gevo's planned Net-Zero 1 facility in South Dakota. These long-term contracts provide the revenue certainty that SAF producers need to secure project financing and reach final investment decision (FID).

Methanol-fueled vessels are entering commercial service. Maersk's first large methanol-capable container vessel, the Laura Maersk, completed its maiden voyage in 2023 and has operated commercially since. As of early 2026, Maersk has 25 methanol-capable vessels on order or in service. The company secured green methanol supply agreements with European Energy, CIMC ENRIC, and Goldwind for initial volumes, demonstrating that dual-fuel vessel design can accommodate both conventional and green fuels during the transition period.

Port infrastructure investment is accelerating. The Port of Rotterdam launched its green hydrogen and ammonia import terminal with an initial capacity of 1 million metric tons per year, targeting maritime fuel supply. Singapore's Maritime and Port Authority (MPA) invested $300 million in bunkering infrastructure for low-carbon fuels, including ammonia and methanol fueling capabilities at Tuas terminal. These investments signal that port operators are preparing physical infrastructure well ahead of fleet conversion timelines.

What's Not Working

Feedstock competition is constraining SAF scale-up. Used cooking oil (UCO), the primary feedstock for HEFA-pathway SAF, faces intense competition from renewable diesel producers and biodiesel blenders. Global UCO supply is estimated at 5 to 6 million metric tons per year, while projected SAF demand alone could require 15 to 20 million metric tons of feedstock by 2030. Companies that rely exclusively on HEFA pathways face supply bottlenecks and rising feedstock costs. The industry needs diversification into alcohol-to-jet (AtJ), Fischer-Tropsch, and power-to-liquid pathways, but these technologies remain at demonstration scale with production costs two to five times higher than HEFA.

Green fuel premiums remain substantial. SAF currently costs $1,500 to $2,500 per metric ton, compared to $600 to $900 for conventional jet fuel. Green methanol trades at $800 to $1,200 per metric ton versus $350 to $500 for conventional marine fuel oil. These premiums are difficult to pass through to consumers: airline ticket surcharges for SAF typically add $2 to $15 per passenger on domestic flights, but corporate buyers with sustainability commitments are absorbing larger proportions through corporate SAF programs. Without robust policy support (blending mandates, production tax credits, carbon pricing), the price gap slows adoption beyond early movers.

Fragmented standards and certification create compliance friction. Companies scaling SAF programs must navigate overlapping sustainability certifications (ISCC, RSB, CORSIA), regional mandates (ReFuelEU, US Inflation Reduction Act Section 40B), and varying lifecycle assessment methodologies. A single SAF production facility may need to maintain three or four certifications simultaneously, adding $500,000 to $1.5 million in annual compliance costs. Harmonization efforts are underway through ICAO and the EU, but convergence is unlikely before 2028.

Phase-by-Phase Scaling Framework

Phase 1: Pilot Validation (Months 0 to 6)

Establish a dedicated cross-functional team with representation from procurement, operations, finance, and sustainability. Select one route or vessel for a controlled SAF or alternative fuel trial. Key deliverables include baseline emissions measurement using verified data, supplier qualification for at least two fuel pathways, and an internal carbon price benchmark. During this phase, United Airlines tested SAF blending at San Francisco International Airport, measuring fuel compatibility, emissions reductions, and operational handling across 100+ flights before expanding to additional hubs.

Phase 2: Commercial Framework (Months 6 to 18)

Negotiate multi-year offtake agreements with at least two fuel suppliers to diversify supply risk. Structure contracts with volume escalation clauses tied to production milestones and price adjustment mechanisms indexed to feedstock costs. Establish book-and-claim accounting procedures if physical delivery is not feasible at all operating locations. Build internal carbon accounting infrastructure that integrates SAF purchases with Scope 1, 2, and 3 reporting systems. CMA CGM, the French container shipping company, executed this phase by signing a green methanol supply agreement with Equinor while simultaneously ordering 12 dual-fuel LNG vessels, creating optionality across fuel pathways.

Phase 3: Operational Integration (Months 12 to 24)

Embed sustainable fuel procurement into standard fuel purchasing workflows rather than treating it as a standalone sustainability initiative. Train fuel handlers, vessel engineers, and ground operations staff on new fuel specifications and handling procedures. Install blending infrastructure at key hubs (for aviation) or bunkering systems (for shipping). Integrate emissions reporting into existing operational dashboards so fuel carbon intensity is visible alongside cost and volume metrics. Alaska Airlines integrated SAF into its standard fuel supply at Seattle-Tacoma International Airport in partnership with SkyNRG, making sustainable fuel part of routine operations rather than a special project.

Phase 4: Scale and Optimize (Months 18 to 36)

Expand to additional routes, ports, or vessel classes based on Phase 3 learnings. Activate corporate SAF programs that allow business customers to purchase SAF certificates, creating additional demand signals and revenue streams. Pursue blending mandates and production incentives through industry coalition engagement. Benchmark against sector peers using frameworks from the Science Based Targets initiative (SBTi) for transport. Continuously optimize route planning, speed management, and load factors alongside fuel switching to maximize total emissions reduction.

KPI Framework for Scaling

KPI	Pilot Phase Target	Rollout Phase Target	Measurement Method
SAF/green fuel share (%)	1-5% of total fuel	10-25% of total fuel	Volume tracking per route or vessel
Lifecycle emissions reduction (%)	50-80% per unit of alt fuel	50-80% per unit of alt fuel	LCA per CORSIA or FuelEU methodology
Total fleet emissions intensity (gCO₂e/tkm or gCO₂e/RPK)	Baseline established	5-15% reduction vs. baseline	GLEC Framework or IATA methodology
Supplier diversification (count)	1-2 qualified suppliers	3+ qualified suppliers	Procurement records
Cost premium management ($/MT over fossil)	Track and report	<150% of fossil fuel price	Financial reporting
Certification compliance rate (%)	100% for pilot volumes	100% for all volumes	Audit records (ISCC, RSB, CORSIA)
Corporate customer participation (%)	N/A	15-30% of B2B customers enrolled	SAF certificate sales records

Key Players

Established Leaders

Neste: The world's largest SAF producer with 1.5 million metric tons per year of renewable fuels capacity across refineries in Porvoo (Finland), Rotterdam (Netherlands), and Singapore. Neste supplies SAF to over 20 airports globally and has signed offtake agreements with more than 30 airlines.

Maersk: The global container shipping leader with 25 methanol-capable vessels on order or in service, representing the single largest fleet commitment to alternative maritime fuels. Maersk has set a 2040 net-zero target and committed to using only green fuels for new vessel orders.

Shell Aviation: A major SAF blender and distributor operating SAF supply chains at airports in Europe, North America, and Asia. Shell invested $2 billion in biofuels and hydrogen through its Renewables and Energy Solutions division.

Emerging Startups

Twelve (formerly Opus 12): Develops power-to-liquid SAF using CO₂ electrolysis and green hydrogen. Signed an offtake agreement with Alaska Airlines and received funding from the US Department of Energy. The E-Jet pathway produces SAF with up to 90% lifecycle emissions reductions.

Prometheus Fuels: Produces carbon-neutral gasoline and jet fuel from atmospheric CO₂ using direct air capture and electrosynthesis. Backed by BMW i Ventures and Y Combinator, targeting commercial SAF deliveries by 2027.

Windship Technology: Designs wind-assisted propulsion systems (rigid wing sails) for cargo vessels. The company's technology can reduce fuel consumption by 20% to 30% on transoceanic routes when combined with route optimization software.

Key Investors and Industry Bodies

Breakthrough Energy Ventures: Bill Gates-backed fund that has invested in multiple SAF producers including LanzaJet, Twelve, and ZeroAvia.

International Maritime Organization (IMO): Adopted the 2023 revised GHG strategy with a net-zero by 2050 target, creating the regulatory framework for maritime fuel transition.

Clean Skies for Tomorrow Coalition (World Economic Forum): Brings together over 80 aviation stakeholders to accelerate SAF adoption, including airlines, airports, fuel producers, and governments.

Action Checklist

1. Conduct a baseline emissions audit across all routes or vessel classes, segmented by fuel type, load factor, and distance.
2. Identify two to three SAF or alternative fuel suppliers and issue requests for proposals with volume escalation terms.
3. Establish an internal carbon price ($50 to $150 per metric ton of CO₂e) to evaluate the business case for fuel switching versus carbon credits.
4. Assign executive ownership of the decarbonization program to a C-suite sponsor with budget authority over fuel procurement.
5. Train operations teams on new fuel handling, safety protocols, and reporting requirements before pilot launch.
6. Integrate sustainable fuel tracking into existing ERP and fuel management systems rather than running parallel spreadsheets.
7. Launch a corporate customer SAF certificate program to share costs and create demand signals beyond internal commitments.
8. Join industry coalitions (Clean Skies for Tomorrow, Getting to Zero Coalition) to influence policy frameworks and share best practices.
9. Set annual KPI targets tied to compensation and board-level reporting for fuel transition milestones.
10. Review and renegotiate offtake agreements annually to incorporate new fuel pathways, price benchmarks, and volume commitments.

FAQ

How long does it take to scale from SAF pilot to fleet-wide adoption? Most airlines report 18 to 36 months from initial pilot blending to establishing SAF as a standard procurement category at primary hubs. Full fleet coverage across all operating airports depends on regional SAF availability and typically takes 5 to 10 years. United Airlines took approximately 24 months from its first SAF flight (2016) to establishing permanent SAF supply agreements.

Can book-and-claim replace physical SAF delivery? Book-and-claim is a legitimate and widely accepted accounting mechanism endorsed by ICAO, the RSB, and the ISCC. It allows companies to claim SAF emissions reductions without physically receiving the fuel, provided the SAF is produced and injected into the fuel system at a certified location. This mechanism is essential for scaling because SAF production facilities are concentrated in a few regions. However, some corporate buyers prefer physical delivery for supply chain credibility.

What is the realistic cost premium for green shipping fuels? Green methanol currently trades at approximately two to three times the cost of conventional heavy fuel oil. Green ammonia is at a similar premium. Costs are expected to decline as production scales: BloombergNEF projects green methanol costs falling to $500 to $700 per metric ton by 2030 if electrolyzer costs continue their current trajectory. Fuel premiums can be partially offset through slow steaming, hull optimization, and carbon credit revenue.

Which alternative maritime fuel has the best near-term scalability? Green methanol has the strongest near-term commercial momentum due to Maersk's fleet commitments, existing bunkering infrastructure compatibility, and lower toxicity compared to ammonia. Ammonia has higher energy density and stronger long-term potential but faces safety challenges and requires entirely new bunkering infrastructure. LNG serves as a transitional fuel but does not achieve deep decarbonization unless paired with carbon capture.

How do companies measure success during the pilot phase? Key metrics include fuel compatibility (zero operational incidents), emissions reduction per unit of alternative fuel consumed (verified via LCA), cost per metric ton of CO₂e abated, and organizational readiness indicators such as trained staff count and updated standard operating procedures. A successful pilot demonstrates not just technical feasibility but commercial viability and operational integration readiness.

Sources

1. International Air Transport Association. "SAF Production and Offtake Tracker." IATA, 2025.
2. International Maritime Organization. "2023 IMO GHG Strategy." IMO, 2023.
3. European Commission. "ReFuelEU Aviation Regulation Implementation Guidelines." EC, 2025.
4. BloombergNEF. "Sustainable Aviation Fuel Market Outlook 2025." BNEF, 2025.
5. Maersk. "Sustainability Progress Report 2025: Fleet Transition Update." A.P. Moller-Maersk, 2025.
6. McKinsey & Company. "Global Maritime Decarbonization Pathways." McKinsey Sustainability Practice, 2024.
7. US Department of Energy. "SAF Grand Challenge Roadmap: Progress Report." DOE, 2025.