INTER AMERICAN UNIVERSITY OF PUERTO RICO · BAYAMÓN CAMPUS
How companies account for SAF purchases toward their emissions targets and what evidence supports their environmental claims.
Sustainable aviation fuel (SAF) is an alternative to conventional jet fuel. Its greenhouse gas savings are measured over the fuel’s life cycle. The result depends on the feedstock, production pathway and energy used to make the fuel.
LIFE-CYCLE EMISSIONS
The calculation accounts for emissions from obtaining the feedstock, processing it into fuel and transporting the fuel. Used cooking oil is one possible feedstock. The same feedstock can produce different results depending on how it is sourced and processed.
Burning SAF still releases CO₂. A life-cycle comparison combines upstream and combustion-stage accounting and compares the total against conventional jet fuel per unit of energy, typically in grams of CO₂ equivalent per megajoule (g CO₂e/MJ).
PRODUCTION PATHWAYS
A pathway describes how a feedstock becomes jet fuel. Buyers need the actual pathway, feedstock and emissions intensity for the batch they fund. The fuel’s technical approval and its sustainability certification answer different questions. Technical approval establishes conditions for use in aircraft. Sustainability certification evaluates criteria such as life-cycle emissions and feedstock sourcing.
| Pathway | How it works | What to check |
|---|---|---|
| HEFA | Hydrogen processing turns oils and fats, such as used cooking oil, into hydrocarbons suitable for jet fuel production. | Feedstock origin, competing uses and whether the claimed waste material can be traced. |
| Fischer–Tropsch | Gasification can turn biomass or suitable wastes into synthesis gas. The Fischer–Tropsch process converts that gas into hydrocarbons. | The share of fossil material in the input and how any avoided landfill emissions were estimated. |
| Alcohol-to-jet | Alcohols such as ethanol are converted into jet-range hydrocarbons. | How the alcohol was produced, including farm inputs, land-use effects and process energy. |
| Power-to-liquid | Electricity can produce hydrogen through electrolysis. The hydrogen and captured carbon can then be used to make synthetic fuel. | The source of the electricity and carbon, plus the assumptions used to calculate the fuel’s emissions intensity. |
Related reading · U.S. Department of Energy · EASA
EDF HANDBOOK READING GUIDE
The Environmental Defense Fund’s handbook by Pedro Piris-Cabezas gives buyers a way to examine the fuel, the claim and the budget together. The links below take you to the relevant pages of the full handbook.
Ask what the analysis counts from feedstock sourcing through combustion. Expanding crop production can change land use directly or shift other production elsewhere. A waste-based pathway can also depend on assumptions about what would otherwise happen to that material. Ask the supplier for the baseline and the evidence behind any credits used.
EDF handbook · Life-cycle assessmentCheck how the supplier addresses land conversion, biodiversity, water and working conditions. Request the proof of sustainability and check which criteria the certification actually covers. Keep the certificate or audit record with the batch documentation.
EDF handbook · SAF requirementsFollow the record from delivery through issuance, transfer and retirement. Ask whether the same reduction has already been assigned to another customer or used under a different program. A registry identifier and retirement beneficiary make the claim easier to audit.
EDF handbook · Avoiding double claimingAsk whether the purchase helps deliver a climate benefit beyond what a mandate would already require. A subsidy may help fund a batch, while the rules of the relevant program determine who can claim its benefit. EDF discusses this distinction in its proposed atmospheric benefit test.
EDF handbook · Atmospheric benefit testThe handbook’s policy examples reflect its publication period. For a purchase decision, check the current rules of the applicable program.
CORPORATE TRAVEL · SCOPE 3
Employee flights on commercial airlines generally fall under Scope 3, Category 6 (Business Travel). Under book and claim, a company can buy the environmental attribute of a documented SAF batch even when the fuel is used on a different flight.
Confirm the fuel volume or energy, proof of delivery or eligible use, the batch’s life-cycle emissions intensity and the fossil reference used in the calculation.
Record the batch and its attribute in a registry. Retire the Scope 3 certificate for the buyer so the same attribute cannot be claimed again by another buyer.
Confirm whether the inventory standard and target framework accept the instrument. Record the reporting period, calculation method, registry details and evidence of retirement.
Who reports what? IATA’s methodology links the airline’s Scope 1 attribute with the corporate customer’s Scope 3 attribute for the same batch. The registry tracks both roles and helps prevent duplicate claims within the same scope.
HYPOTHETICAL EXAMPLE
Multiply the SAF energy by the difference between the fossil and SAF emissions intensities. Divide by one million to convert grams of CO₂e to metric tons.
At the starting values, 100,000 MJ × (89 − 30) g CO₂e/MJ yields 5.9 metric tons of CO₂e in estimated life-cycle reductions. Change any input to see how the result moves.
ILLUSTRATIVE PROCUREMENT CASE
Suppose a company’s business travel inventory shows 120 metric tons of CO₂e and the purchase in the calculator costs an additional $1,770. The buyer can evaluate the 5.9 metric tons associated with the certified fuel as a separate figure while reviewing eligibility. Using the same boundaries, 5.9 tons is about 4.9% of the travel inventory and the illustrative premium is $300 per metric ton of CO₂e.
Estimate travel emissions from the company’s activity data. Ask potential suppliers for the specific reporting scheme, registry, delivery evidence, feedstock, fuel pathway and emissions intensity. Clarify who receives each attribute and whether a mandate or other claim already applies.
Match the supplier’s documents to the registry record and confirm that the retirement names the correct buyer and period. Keep a record of the gross inventory, the purchased reduction, the applicable framework and how the purchase was reflected in the target disclosure.
Document the eligibility decision. If it allows a direct deduction under the same reporting boundary, the illustrative figure would be 114.1 metric tons. Explain the gross figure, the deduction and its supporting evidence so readers can reproduce the calculation.
Report the 120 metric tons on the inventory’s existing basis. Where the reporting framework allows, describe the purchase and its estimated benefit in a separate disclosure. Check that public statements match how the company reports progress toward its target.
Related reading · GHG Protocol · Business Travel · IATA · SAF Procurement · EDF handbook · SAF premium and emissions reduction cost
Waste oils and other residues have competing uses. A supply plan should account for how much traceable material can be collected without depending on unsustainable sources as demand grows.
Commercial plants require capital and dependable demand. An offtake agreement can give producers more confidence to invest. Buyers can compare offers on the premium paid per metric ton of verified life-cycle reduction.
Power-to-liquid production depends on low-emissions electricity and a suitable carbon source. Physical SAF also needs blending and access to a fuel supply system. Book and claim lets buyers support eligible fuel delivered elsewhere, while the registry tracks who can claim its benefit.
Airline compliance programs, corporate inventories and government accounts can serve different purposes. Check where a reduction has been recognized and whether any transfer or reporting adjustment is needed. The EDF handbook gives policy examples for domestic and international aviation.
Related reading · EDF handbook · Government accounting · ICAO Environmental Report 2025
GREENWASHING
This overstates what the purchase supports. The aircraft still produces emissions, and the certificate can be tied to SAF delivered elsewhere.
This hypothetical claim gives readers a quantity and identifies the underlying action. The company would support it with the calculation, certificate and registry retirement record.
KNOWLEDGE CHECK
A company buys and retires a certificate for SAF delivered into a fuel supply system elsewhere. What can the company substantiate with a verified certificate and calculation?