Turn ticket sales into demand for sustainable aviation fuel

Submitted through the COP31 Sustainable Transformation Awards · SKD Türkiye (WBCSD Global Network Partner)

The company is a commercial airline in the services sector with more than 1,000 employees, reporting its climate performance through an integrated annual report (1).

Aviation has few decarbonisation levers that work on the existing fleet. Sustainable aviation fuel is the main one, because it can be used in aircraft already flying and through infrastructure already built, which is why it dominates the sector's transition planning.

The constraint is supply, not technology. Sustainable aviation fuel is globally scarce and costs substantially more than conventional jet fuel, so the volume an airline can procure is limited by cost and availability rather than by intent.

Scarcity of that kind is partly a demand problem. Producers scale against visible, contracted demand, and demand that exists only as corporate commitment is harder to act on than demand that appears as recorded transactions.

At the same time passengers are structurally passive in this transition. They generate the emissions of a flight but have no mechanism at the point of purchase to act on them, and the mechanisms that do exist are usually offsets, which fund emission reductions elsewhere rather than changing the fuel in the aircraft.

The company introduced a voluntary option on 1 July 2025 to close that gap, going beyond what regulation requires.

Location of the initiative: Türkiye, with the option offered through the airline's web and mobile sales channels on all routes

The Additional SAF Option is a voluntary ancillary service offered to passengers on the web and mobile sales channels, through which they can support the use of sustainable aviation fuel.

It sits inside the existing purchase path. The option is presented during ticketing and ancillary service purchase, at the moment a passenger is already transacting, rather than on a separate page that would require them to seek it out.

What the contribution buys is defined physically rather than financially. Contributions are linked to the procurement of certified sustainable aviation fuel of international validity, which is then used on flights, so the passenger is funding fuel that enters an aircraft rather than an emission reduction elsewhere.

The commitment carries a deadline. Fuel associated with the contributions is procured and used within the 12 months following the flights against which the contributions were made, which turns an open-ended promise into a bounded and auditable one.

Traceability is built into the design. The environmental effect is tracked through the certificate information of the fuel supplied, life cycle emission factors and the relevant calculation methodologies, and the process is planned to be reported with third-party verification.

The passenger option has a corporate counterpart. A separate Corporate SAF Programme supports the same fuel on the corporate customer side, so the two together cover both individual and business demand.

The model is currently active and scaling on the web and mobile channels, with work continuing to extend it to agency sales channels.

Figure 1: The Additional SAF Option as it appears at the ancillary services stage of the web booking flow, where passengers choose one of three contribution packages.

Figure 2: Monthly trend in passenger participation in the Additional SAF Option, indexed to July 2025, the launch month, as the reference period.

Sustainability impact

Climate

The initiative addresses Scope 1 emissions — the jet fuel burned in aircraft the airline operates — because the certified sustainable aviation fuel procured against passenger contributions is used on the company's own flights rather than credited from elsewhere.

For the period from July 2025 to July 2026, contributions made by passengers are expected to create a reduction potential of approximately 95 tonnes of CO2e, on a calculation based on the average sustainable aviation fuel procurement cost.

That figure is an expected potential rather than a completed reduction. The final amount will be established once the fuel has been procured and used, using the certificate information of the fuel supplied and its life cycle emission values. The amount is calculated under the ICAO methodology for sustainable aviation fuel emission reductions; third-party verification has not yet been carried out.

The calculation route is deliberately physical: the reduction follows from the volume of certified fuel actually bought and burned, and its life cycle emission factors, rather than from the value of contributions received.

Social

The measured social outcome is participation. Between the launch in July 2025 and May 2026 the number of contributing passengers grew by 133.7 per cent, reaching 2.34 times the level of the launch period.

That growth is the point of the initiative as much as the fuel volume. It indicates that awareness of low-carbon aviation solutions strengthens when a concrete action is available at the moment of purchase, rather than remaining an abstract concern.

The design also changes the passenger's role. Passengers move from being the recipients of an airline's transition plan to being active participants in it, with a visible mechanism through which their choice reaches the fuel supply chain.

Clear communication is part of the social obligation. The scope of what a contribution does — and does not — cover has to be explained plainly, since a voluntary environmental option that passengers misunderstand damages trust in the mechanism rather than building it.

Business impact

Benefits

Participation grew measurably. The number of contributing passengers in May 2026 was 133.7 per cent higher than in July 2025, reaching 2.34 times the starting level, which demonstrates that the option scales with exposure rather than saturating quickly.

The initiative produces a traceable demand signal for sustainable aviation fuel. Recorded contributions linked to certified procurement give the airline evidence of passenger-side demand that supports its fuel supply planning and negotiation, which corporate commitments alone do not provide.

Marginal cost is low because the option runs on digital sales infrastructure the airline already operates. Once integrated, each additional contribution costs almost nothing to process.

It complements the corporate channel. The passenger option and the Corporate SAF Programme address individual and business demand for the same fuel, which gives the airline two routes to the same supply commitment.

The reporting environment supports credibility. The company reports through CDP, produces reporting aligned with ISSB under IFRS S1 and S2 and with TCFD, and obtains independent third-party external assurance, so an initiative built for traceability fits an existing disclosure structure rather than requiring a new one.

Costs

The build cost is the integration into the web and mobile sales channels: designing the option into the ticketing and ancillary purchase flow, and connecting the resulting contributions to procurement and reporting records.

The running cost is coordination. Sustainability, ancillary services, digital sales channels, fuel procurement, financial tracking and reporting all have to act on the same records, because contribution collection, fuel purchase and verification sit in different departments.

The dominant external cost is the fuel itself. Limited global supply of sustainable aviation fuel means high price levels, which is the principal risk to scaling the model and is outside the airline's control.

Clear passenger communication is a continuing requirement rather than a launch task, since the mechanism only works if passengers understand what the contribution funds.

Extending to agency sales channels requires further integration work with intermediaries, which is why the model reached the direct digital channels first.

Impact beyond sustainability and business

Co-benefits

The mechanism makes latent demand visible. Passenger willingness to pay for lower-carbon fuel existed before the option and had no way to express itself; recording it converts sentiment into data that fuel suppliers and planners can use.

It is transferable without proprietary technology. Any carrier with a digital sales channel and access to certified fuel supply can build the same path, and the model also extends to other customer touchpoints beyond direct digital sales.

The complementary corporate programme means the airline can aggregate individual and business demand into a single supply requirement, which is a stronger position with fuel suppliers than either channel alone.

Potential side-effects

The main risk is misreading. A voluntary contribution presented at booking can be understood as an offset, which it is not — it is tied to the physical procurement and use of certified fuel. If that distinction is not communicated clearly, the initiative inherits the credibility problems of offsetting without the benefit.

Supply constrains the outcome. Limited global availability and high cost of sustainable aviation fuel cap the volume that contributions can convert into fuel, so participation growth does not translate proportionally into emission reduction.

The reduction depends on the life cycle emission values of the fuel actually supplied, which is why the figure for the period is stated as a potential and will only be fixed once procurement, use and verification are complete.

There is a structural question about voluntary mechanisms in general: a passenger-funded contribution places part of the transition cost on the customer. The airline's own fuel strategy and the corporate programme have to remain the primary route, or the voluntary option becomes a substitute for it rather than an addition.

Finally, participation growth measured from a launch month starts from a low base. Sustaining the trend as the base grows is a different problem from establishing it.

Typical business profile

The model suits transport operators that sell directly to end customers through digital channels and that buy a fuel with a certified low-carbon alternative — airlines first, but the structure applies to shipping and long-distance road transport where certified fuels exist.

It requires an existing digital sales platform with an ancillary services capability, access to certified fuel supply with credible certificate information, and an internal reporting function able to hold the audit chain.

Delivery engages sustainability, ancillary services, digital sales, fuel procurement, financial tracking and reporting functions working to a shared record, and is most relevant to organisations already reporting under external assurance.

Approach

1. Place the option inside the existing purchase flow: Add the contribution to the ticketing and ancillary purchase steps of the direct digital channels rather than building a separate destination, so it reaches customers at the moment they are already transacting and needs no additional acquisition effort.

2. Define in physical terms what a contribution buys: Commit that contributions are linked to procurement of certified Sustainable Aviation Fuel of international validity and to its actual use in operations, so the customer funds fuel rather than a credit, and the claim can be evidenced by certificate.

3. Attach a delivery window to the commitment: Undertake to procure and use the fuel within a defined period of the journeys against which contributions were made — 12 months in this case — so the obligation has a date against which it can be audited rather than remaining open-ended.

4. Fix the participation baseline at launch: Take the launch month as the reference point, July 2025 here, and measure growth against it, so participation is reported against a defined starting level rather than against a moving average that hides the trend.

5. Coordinate the functions that have to act on the same record: Bring sustainability, ancillary services, digital sales, fuel procurement, financial tracking and reporting into one working structure, because collection, purchase and verification sit in different departments and the audit chain breaks wherever they do not reconcile.

6. Track participation as the primary indicator: Monitor the number of contributing customers, the participation index against the launch month and the usage trend by sales channel, since fuel volume follows participation and participation moves first.

7. Prepare for third-party verification from the outset: Keep digital sales data, internal reporting records and fuel procurement documents in a form an external verifier can follow, rather than reconstructing the audit trail after the fact when certificate detail is hardest to recover.

8. Extend to indirect channels once the direct path is proven: Work through the integration required with agencies and intermediaries, so the option reaches customer segments that do not book directly and the model stops being limited to the operator's own platform.

Stakeholders involved

• Project leads: The initiative is owned at senior management level within the company's sustainability strategy and low-carbon transition approach, rather than sitting inside a single commercial function. Responsible positions are structured so that passenger participation, fuel procurement, traceability and verification are managed together, which is what keeps the customer-facing promise and the fuel purchase aligned.

• Company functions: Sustainability sets the methodology and the reporting requirements. Ancillary services and digital sales channels own the customer-facing integration and the accessibility of the option in the purchase flow. Fuel procurement converts contributions into certified fuel supply. Financial tracking and reporting hold the records that connect the two and support verification. Continuity is maintained through the existing digital sales infrastructure, procurement processes, internal reporting systems and the coordination mechanism between these units.

• Main providers: Business partners in the sustainable aviation fuel supply process are central, since they provide both the certified fuel and the certificate information that links contributions to physical fuel of international validity. Independent organisations are to carry out third-party verification of the process. Sales channels and agencies act as distribution partners as the option is extended beyond the direct digital channels.

• Other: Passengers are the main participating stakeholder, exercising a voluntary choice during ticketing and ancillary purchase. Corporate customers participate through the complementary corporate programme on the same fuel. The feedback mechanism runs on digital sales data, passenger usage trends, internal reporting outputs, feedback received from sales channels and the findings that arise during verification, so customer behaviour, procurement and channels develop together.

Key parameters to consider

The option was launched on 1 July 2025 on the web and mobile sales channels, and the base year for measurement is 2025, the year of launch. Impact data covers 1 July 2025 to August 2026, and the expected emission reduction figure covers July 2025 to July 2026.

The fuel delivery window is 12 months from the flights against which contributions were made, which sets the reporting rhythm for the whole mechanism.

Indicators are the growth rate in the number of contributing passengers, the participation index against the launch period, the usage trend across the web and mobile sales channels, and the completion status of the certified fuel procurement process.

Monitoring runs on digital sales data, internal reporting records and fuel procurement documents. The company reports through CDP, produces reporting aligned with ISSB under IFRS S1 and S2 and with TCFD, and obtains independent third-party external assurance.

Channel coverage is the main development parameter: the option is active on direct digital channels, and extension to agency sales channels is in progress, which is the step that determines how far the model reaches into the total passenger base.

Implementation and operations tips

Keep the mechanism physical. Tying contributions to certified fuel procurement and use, with a stated delivery window, is what separates this from an offset and is the single design choice that carries the credibility of the whole initiative.

Report participation and reduction separately. Participation is measured and growing; the emission reduction for the period is an expectation until procurement is complete. Presenting them as one number would overstate what has been achieved.

Design the audit trail before launch. Certificate information, sales records and procurement documents are far cheaper to keep in verifiable form from the start than to reconstruct when an external verifier asks.

Treat the voluntary option as an addition to the fuel strategy, never as the strategy. Its value is the demand signal and the participation it creates, and both weaken if the mechanism is presented as the operator's principal answer.

External links

• Sustainability reports

• CDP reporting

• ISSB / TCFD aligned reporting

• Independent third-party external assurance

Source list

(1) Integrated annual report