Sustainable Aviation Fuels (SAF) are now at the center of the debate on the decarbonization of aviation. They are mentioned in policies, industrial roadmaps, and sustainability strategies as one of the most promising solutions to reduce the environmental impact of air transport.
However, between the recognition of their potential and their actual large‑scale deployment, there is a significant gap, made up of technical, operational, and infrastructural complexities that are often underreported.
What are Sustainable Aviation Fuels (SAF)
Sustainable Aviation Fuels (SAF) are alternative fuels to conventional jet fuel, designed to operate in existing aircraft engines without significant modifications. Their main feature is that they come from non‑petroleum feedstocks, such as waste oils and fats, agricultural or municipal waste, and CO₂ captured from the atmosphere.
From a chemical and performance standpoint, these fuels aim to replicate traditional kerosene properties as closely as possible, maintaining safety, reliability, and energy density compatible with the requirements of civil aviation.
Why are SAF considered a key solution for the decarbonization of aviation
The aviation sector is among the most difficult to decarbonize because it requires high‑energy‑density fuels and established global infrastructures.
SAF are considered an important lever because they can significantly reduce CO₂ emissions across the entire life cycle, reaching values comparable to net‑zero targets, and they allow the use of existing fleets with minimal modifications.
Are SAF really sustainable?
The sustainability of SAF is not automatic, but depends on several factors:
- type of feedstock used, which determines the actual emissions balance and the impact on land use and food supply chains.
- efficiency and impact of the production process
- availability and competing uses of raw materials
Not all feedstocks have the same emissions profile or social impact. For example, using waste oils or residues reduces impacts compared to dedicated crops that could compete with food production or land use.
How are Sustainable Aviation Fuels produced today
There are four main technological pathways to produce SAF:
- Alcohol-to-Jet (AtJ) – converts bioethanol into SAF through dehydration followed by synthesis, integrating technologies such as Hummingbird® to convert ethanol into ethylene.
- HEFA (Hydroprocessed Esters and Fatty Acids) – the most widely applied technology today, hydroprocessing oils and fats to obtain high‑quality fuels.
- Gasification Fischer-Tropsch (GFT) – converts biomass or waste into syngas and then into hydrocarbons through Fischer‑Tropsch synthesis.
- Power-to-Liquids (PtL) – uses green hydrogen and captured CO₂ to synthesize fuels through electrochemical processes, the most sustainable but also the most expensive pathway.
These technologies are already in commercial application across several global projects, involving collaboration among major industry players.
If the technologies exist, why aren’t SAF yet deployed on a large scale?
Although technologies to produce SAF are mature or rapidly developing, large‑scale production remains limited for several reasons:
- high production costs, linked to processes that still require a lot of energy, limited sustainable feedstocks, and high plant investment costs, making it difficult to reach economic parity with fossil jet fuel.
- limited availability of sustainable feedstocks
- complexity of the plants and the need for advanced engineering expertise
- operational continuity requirements and certifications
These barriers make it difficult to move from pilot production to a widespread industrial system.
How to transport SAF?
Along the path from storage to distribution, one of the most delicate operational aspects is the handling of fluids: extraction, transfer, and loading toward tanks, tank trucks, or distribution facilities, while maintaining product quality and minimizing risks. For SAF — which are often stored or blended in large tanks and must maintain high purity standards — this is where specific technologies such as floating suction arms demonstrate their practical value.
Floating suction arms are devices designed to draw liquid from the upper layer of the tank, avoiding the extraction of deeper layers where impurities, water, or sediments may accumulate.
The arm’s inlet remains covered by clean liquid thanks to a system of floats that follow the level of the product. This allows:
- reducing the possibility of product contamination, maintaining SAF integrity during handling;
- obtaining a more uniform product with consistent quality, particularly important when sustainable fuel is blended with other components;
- ensuring cleaner and safer operations, reducing the risk of drawing unwanted material that could compromise downstream processes.
Floating suction arms are available in various models for underground or aboveground tanks, with materials suitable also for ATEX environments, and configurations that allow adaptation to different operational conditions in fuel depots.
In essence, integrating floating suction arms into SAF management supports not only the physical handling of the fuel but also the operational quality and sustainability of the entire sustainable aviation fuel supply chain.
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