Report Warns Tankering Fuel Could Undermine EU’s SAF Mandate

Aircraft refueling
Credit: Amazon

A common practice used by airlines to reduce fuel costs could undermine the objectives of a planned EU mandate to blend sustainable aviation fuel (SAF) with fossil jet fuel starting in 2025, an environmental organization has warned.

Tankering is the practice whereby an aircraft carries more fuel than required for its next flight in order to reduce or avoid refueling at the destination airport. 

A new report by the International Council on Clean Transportation (ICCT) said this practice of uplifting cheap fuel at one airport to avoid purchasing more expensive fuel at another could enable airlines to evade the EU’s SAF mandate.

Carrying more fuel than necessary increases the aircraft’s weight and therefore its fuel consumption and the amount of CO2 emitted.

In a 2019 study, Eurocontrol estimated 16.5% of European flights could perform full tankering and 4.5% partial tankering. If used to this extent, the practice would result in the burning of 286,000 metric tons of additional fuel and production of 901,000 metric tons of unnecessary CO2 emissions, Eurocontrol calculated. But tankering would save European airlines €264 million ($319 million).

SAFs are significantly more expensive than jet fuel. This raises concerns that once the EU’s mandate takes effect, airlines could exploit tankering to uplift additional fossil jet fuel at non-EU airports to avoid purchasing the more expensive SAF blends, the ICCT said.

“We find that tankering should be minimal in 2025 but could increase substantially as the relative share of SAF in the fuel mix increases,” the ICCT predicted. “By 2035, tankering could reduce SAF sales by 22% at EU airports and increase systemwide fuel use by 0.9%.” The analysis assumes adjoining countries such as the UK and Switzerland do not adopt equivalent SAF mandates.

The European Commission’s pending RefuelEU aviation legislative initiative is expected to introduce a SAF mandate under which fuel sellers at EU airports would be required to blend an increasing fraction of SAF into jet fuel starting in 2025. The goal is to stimulate demand and ramp up production for SAF.

However, legislation that obligates fuel providers to provide SAF but does not require that airlines purchase the blended fuel “would leave open the possibility that they could evade the SAF mandate by tankering,” the ICCT said.

Reducing tankering could support SAF sales and safeguard the integrity of mandates, the organization said. Three approaches are possible, the ICCT said: obligating airlines to purchase SAF; defining and then prohibiting the carriage of “excess” fuel; and encouraging neighboring nations such as the UK and Switzerland to adopt equivalent SAF mandates.

Graham Warwick

Graham leads Aviation Week's coverage of technology, focusing on engineering and technology across the aerospace industry, with a special focus on identifying technologies of strategic importance to aviation, aerospace and defense.


I clearly do not understand how Carbon Emissions are "weighed", but is it possible that "burning of 286,000 metric tons of additional fuel" will produce 901,000 metric tons of unnecessary CO2 emissions," ?
In response to Mario, fuels are mostly made of carbon and hydrogen. When you burn them, they combine with oxygen in the atmosphere to produce CO2 and H2O. A CO2 molecule weighs about 3.5 times as much as a single carbon atom, so if all 286,000 tons of fuel are completely burnt, you'd expect roughly 3.5 times that mass in CO2, or close to 1,000,000 metric tons
Thanks for the explanation, Zephyxj. I see (I think), but I'm still trying to wrap my head around molecular weight vs. the weight of a solid....time to dig out my old chemistry book!