Sustainable Aviation Fuels (SAF) and Their Role in Air Cargo Transportation

Air transportation provides businesses with the speed required for international delivery, but aviation remains a source of harmful atmospheric emissions. One of the industry's key objectives is therefore to develop and introduce technologies that can reduce its carbon impact without abandoning existing infrastructure. Sustainable Aviation Fuel (SAF) is regarded as a major tool for this transition. Below, we examine what SAF is made from, how it is used in cargo aviation, and what prevents broader deployment.

What Is Sustainable Aviation Fuel (SAF)?

SAF is a general term for sustainable aviation fuel whose environmental impact is assessed across its entire life cycle. The assessment includes feedstock sourcing, production, transportation, and use, rather than only emissions from combustion. Different types of SAF deliver different results.

SAF can be used as a neat fuel where the feedstock and production process meet the applicable criteria. It is produced through different technological pathways and from feedstocks that satisfy sustainability requirements. Certain types can be blended with conventional kerosene, so the transition does not require an immediate overhaul of the entire aircraft fleet.

What Is SAF Made From?

SAF production uses biogenic feedstocks, waste, residues, and components for synthetic fuels. The feedstock must meet sustainability criteria. The choice depends on the technology, feedstock availability, and sustainability requirements. The main options include:

• Used vegetable oils and animal fats;
• Agricultural and forestry residues;
• Certain types of organic waste;
• Sugars and alcohols of biogenic origin;
• Hydrogen and carbon for synthetic fuel.
  

Not every aviation biofuel is automatically considered sustainable: the production chain must comply with the established requirements. One common pathway is HEFA, based on processing oils and fats. Fischer-Tropsch and Alcohol-to-Jet technologies are also used, while Power-to-Liquid using electricity from renewable sources is being considered for long-term development.

How SAF Aviation Biofuel Differs from Conventional Aviation Fuel

The main difference between SAF and conventional aviation fuel lies in the origin of the feedstock and the carbon cycle. Conventional jet fuel is produced from fossil petroleum, whereas SAF uses alternative feedstocks such as used vegetable oils, animal fats, waste, and other resources depending on the technology. SAF therefore makes it possible to replace part of the fossil-based fuel without changing the product's primary purpose.

The production chain also differs. SAF undergoes additional processing and certification, after which its characteristics must comply with aviation fuel requirements. In terms of operating properties, certified SAF must be compatible with existing aircraft and infrastructure within the permitted blending ratio. For a number of pathways, ASTM D7566 allows SAF content of up to 50%, so today the focus is primarily on gradually replacing conventional kerosene rather than eliminating it entirely.

Why the Aviation Industry Is Transitioning to SAF

One of the main reasons for the transition is the need to reduce aviation's carbon footprint without rapidly replacing the existing aircraft fleet and infrastructure. For long-haul transportation, liquid aviation fuel remains a key energy source, so reducing its carbon intensity is regarded as one practical way to decarbonize the industry.

At the same time, the effect of SAF cannot be assessed solely on the basis of emissions produced during flight. The entire fuel life cycle must be considered, from feedstock sourcing to use in the engine. This is why comparisons between SAF and conventional kerosene analyze the overall environmental impact.

Regulators are also creating demand. For example, the ReFuelEU Aviation rules set a minimum share of SAF in fuel supplied at EU airports: 2% from 2025 and 6% from 2030. In other words, for airlines, the use of low-carbon aviation fuel is becoming a market requirement rather than merely a voluntary initiative.

Reducing Aviation Emissions and the Carbon Footprint

The main environmental benefit of SAF is not that an aircraft stops emitting CO₂ when the fuel is burned. Emissions during flight remain, so carbon-footprint reduction is assessed across the entire fuel life cycle, from the sourcing of the original feedstock to its use on board.

This approach shows how much emissions are generated during the production and delivery of SAF and how this compares with conventional aviation fuel. When calculating fuel life-cycle emissions, the following stages are taken into account:

1. Feedstock sourcing and preparation.
2. Feedstock processing and SAF production.
3. Fuel transportation and distribution.
4. Fuel combustion in an aircraft engine.

It is the combined result that makes it possible to determine how much a specific type of SAF reduces carbon impact compared with fossil aviation fuel. It is therefore incorrect to describe all SAF as equally environmentally friendly: the outcome depends on the feedstock, production technology, energy inputs, and the entire supply chain.

The Role of SAF in Aviation and the Decarbonization of Air Transportation

Sustainable fuel is part of the decarbonization strategy alongside fleet renewal, improved fuel efficiency, and route optimization. Its purpose is to reduce the carbon footprint while preserving the advantages of air transport.

SAF Biofuel in Air Cargo Transportation

The air cargo sector is particularly sensitive to fuel costs because they affect flight economics. At the same time, air cargo transportation is essential for valuable and urgent shipments where air transport is difficult to replace.

How Sustainable Aviation Fuel Is Used in Cargo Aviation

SAF is used in cargo aviation as a fuel component for regular cargo flights. It is blended with conventional aviation kerosene in an approved proportion, after which the resulting fuel blend is loaded into the aircraft and used during flight. In practice, the use of SAF involves several stages:

1. Delivering the fuel to the airport.
2. Blending SAF with aviation kerosene.
3. Refueling the aircraft with the resulting blend.
4. Operating the cargo flight.

Thus, SAF does not change the cargo transportation process itself: the aircraft operates the flight as usual, but part of the fossil fuel is replaced with sustainable aviation fuel.

Impact of SAF on the Environmental Performance of Air Logistics

SAF makes air logistics more environmentally sustainable by reducing greenhouse gas emissions compared with conventional aviation fuel. The effect is assessed not only by emissions during the flight but also across the fuel's entire life cycle, from feedstock production to use. The overall reduction in environmental impact is influenced by:

• The type of feedstock and SAF production technology;
• The proportion of SAF in the fuel blend;
• Emissions generated during fuel production and transportation;
• Fuel-use efficiency in cargo transportation.
  

Accordingly, the lower the total life-cycle emissions of SAF, the more significant its environmental benefit for air logistics. SAF should therefore be compared with conventional aviation fuel across the full life cycle, rather than only by the volume of emissions generated during the flight.

Advantages of SAF for Cargo Aviation

SAF makes it possible to reduce carbon impact without immediately rebuilding the fleet or the entire refueling system. In international logistics, air transport is chosen for its speed and because alternative delivery methods have limitations. The main advantages include:

• Lower life-cycle emissions;
• Compatibility of a number of certified SAF types with existing infrastructure;
• The ability to account for environmental indicators in reporting;
• Support for international decarbonization programs;
• Gradual implementation without a complete fleet overhaul.
  

More environmentally sustainable air transportation is becoming part of the requirements of companies for which safety, effective control, and verifiable results are important. The key benchmark is a socially and environmentally responsible approach.

What Limits the Widespread Adoption of SAF

The adoption of SAF is constrained by several factors. Production capacity on the global market is unevenly distributed, and in 2026 output accounts for only about 0.8 percent of aviation fuel consumption. In practice, the following factors are important:

• Limited availability of suitable feedstock;
• High production costs;
• Uneven geographic distribution of production facilities;
• Insufficient utilization of existing capacity.
  

The price of SAF depends on the technology, feedstock, investment, and market conditions. Increasing supply therefore requires both expanding production and maintaining stable demand.

For SAF production to grow, investment, clear rules, and stable demand are needed. Without coordinated development of the energy sector, aviation, and regulation, even existing production capacity may remain underutilized.

Prospects for SAF in Air Cargo Transportation

The market will expand through several technological pathways. HEFA remains a commercially viable route, Fischer-Tropsch and Alcohol-to-Jet make it possible to use other types of feedstock, while e-SAF is produced from hydrogen and carbon using renewable energy. Market development will depend on several conditions:

• Expansion of SAF production;
• Availability of the fuel at a greater number of aviation hubs;
• Development of carbon-footprint accounting systems;
• Lower costs as production scales up.
  
  Today, SAF still cannot be regarded as a complete replacement for conventional fuel across all applications. However, the technology has successfully moved from testing individual solutions to commercial use, while requirements for emissions reductions are becoming stricter. Further development will depend on production volumes, availability, and the demonstrable sustainability of the feedstock.