Yes, used cooking oil (UCO) can genuinely be converted into sustainable aviation fuel (SAF), and it already is on a commercial scale. Through a refining process called hydroprocessing, waste vegetable oils and animal fats are chemically transformed into a jet fuel substitute that meets strict aviation safety standards, cuts lifecycle carbon emissions by up to 80%, and can be blended directly into existing aircraft engines without modification.

How Used Cooking Oil Becomes Jet Fuel

The transformation from a deep fryer to a fuel tank is more technical than it sounds. Waste oil is first collected, filtered, and cleaned of food particles and water. It then goes through a process known as HEFA (Hydroprocessed Esters and Fatty Acids), which is currently the most widely certified pathway for producing SAF from lipid-based feedstocks.

• Pretreatment: Removing contaminants, free fatty acids, and moisture from the collected oil.
• Hydrogenation: Adding hydrogen under high pressure and heat to remove oxygen molecules and saturate the fat chains.
• Isomerization and cracking: Restructuring the molecules so the fuel behaves correctly at high altitude and low temperatures.
• Fractionation: Separating the final product into usable jet-fuel-grade hydrocarbons.

The result is a fuel that is chemically almost identical to fossil-based kerosene, which is why it can be blended (typically up to 50%) with conventional jet fuel and used in existing aircraft without engine redesign.

Why Airlines and Governments Are Betting on This Feedstock

Cooking oil is attractive as a SAF feedstock because it’s already a waste product — it doesn’t compete with food crops or require new farmland, unlike first-generation biofuels. This overlaps with broader research into advanced biofuels that prioritize non-food, circular feedstocks over traditional crop-based ones.

Airlines are under increasing regulatory pressure (particularly in the EU, under the ReFuelEU Aviation mandate) to blend a growing percentage of SAF into their fuel supply each year. Since electric or hydrogen-powered commercial jets remain decades away from viability for long-haul flights, drop-in biofuels like UCO-based SAF are currently the most realistic decarbonization tool for aviation.

The Supply Chain Challenge

The biggest obstacle isn’t the chemistry — it’s the collection. Only a fraction of the world’s used cooking oil is actually recovered from restaurants, food processors, and households; much of it is still disposed of improperly. This has created a competitive global market where UCO is shipped internationally to refineries, and it has also opened the door to fraud, with some suppliers mislabeling virgin palm oil as „used” oil to qualify for green subsidies.

To address these supply constraints, the industry is increasingly looking at complementary feedstocks derived from biological waste streams, similar to the strategies discussed in biodiesel and bioethanol production research, where diversifying inputs improves both scalability and traceability.

Key Limitations to Consider

• Limited global volume of authentic waste oil compared to aviation’s total fuel demand
• Higher production costs than fossil jet fuel, though prices are gradually falling
• Verification and certification challenges to prevent fraudulent „waste” labeling
• Logistics and cross-border transport emissions from oil collection networks

„A single long-haul flight can require tens of thousands of liters of fuel — which is why scaling waste-oil-based SAF sustainably will require multiple feedstocks working together, not one single solution.”

Fun Fact

The first commercial passenger flight partly powered by used cooking oil took off back in 2011, when a KLM flight from Amsterdam used a 50% biofuel blend derived from waste cooking oil — proving over a decade ago that the technology was already viable, long before most consumers had heard the term „SAF.”

Is This the Future of Air Travel Fuel?

Used cooking oil won’t single-handedly decarbonize global aviation — supply volumes simply aren’t large enough. However, it plays an important transitional role while other pathways mature, including power-to-liquid synthetic fuels and biomass-derived options discussed in broader work on biotechnology in renewable energy. As collection infrastructure improves and certification standards tighten to prevent fraud, cooking-oil-based SAF is expected to remain one of the fastest, most cost-effective tools airlines have for cutting emissions this decade.

Frequently Asked Questions

Is SAF made from used cooking oil actually safe for jet engines?

Yes. It undergoes rigorous certification (ASTM D7566) and is chemically refined to match the performance specifications of conventional jet fuel, including cold-temperature stability at cruising altitude.

How much cheaper or more expensive is UCO-based SAF compared to regular jet fuel?

It’s currently more expensive — often 2 to 4 times the cost of fossil jet fuel — due to limited feedstock supply and refining infrastructure, though costs are expected to decrease as production scales.

Can 100% of a plane’s fuel be replaced with used cooking oil SAF?

Currently, blending limits (usually up to 50%) are enforced for certification and safety reasons, though research into 100% drop-in SAF blends is actively underway.

Does using cooking oil for fuel compete with food supply?

No, because it uses oil that has already been used for cooking and would otherwise be discarded, unlike biofuels made from virgin crop oils.

What happens if there isn’t enough used cooking oil to meet demand?

Producers are diversifying into other waste-based feedstocks, including animal fats, algae oils, and agricultural residues, to avoid over-reliance on a single limited resource.