Welcoming an Age of Sustainable Flight

(Neste) Lufthansa’s Katja Kleffmann tells Satu Dahl how the airline is succeeding in its bid to make aviation greener.
Globally, we are witnessing a surge in sustainability innovation—from new forms of propulsion to smarter, more energy-efficient buildings. And one of those initiatives is sustainable aviation fuel.

Sustainable aviation fuel (SAF) to power flights is an excellent route to a more sustainable aviation. Just look at the numbers: Sustainable jet fuel has a carbon footprint that’s up to 80% smaller than traditional fossil jet fuel.

Katja Kleffmann is Lufthansa Group’s head of supply and trading, Fuel Management LH Group. She explains how they made the change to more sustainable flights.

The will to succeed
Lufthansa Group’s commitment toward sustainable aviation is well known: The largest airline group in Europe demonstrated its commitment in 2011 when Lufthansa became the first airline in the world to test alternative fuel in regular flight operations.

The airline conducted its first trial flight in July 2011, on the very day that sustainable aviation fuel was approved for use on commercial flights.

Lufthansa conducted its first trial flight with sustainable aviation fuel on the very day it was approved for use on commercial flights.

The huge trial involved transporting passengers on commercial flights between Hamburg, Germany, and Frankfurt. The flights were powered by a 50/50 blend of sustainable aviation fuel and fossil fuel—the maximum blend ratio allowed. The trial period took place over six months in collaboration with Neste, which supplied the fuel.

“The performance of the fuel was first tested in unusual situations such as ‘engine relight in flight’ where the engine shuts down suddenly,” Kleffmann explains. “The fuel performed normally, and we then began to contract sustainable aviation fuel from Neste right away.”

But was it all smooth sailing? As with all pioneering projects, there were great highs but, naturally, some challenges to be overcome, too.

Early tests and high hopes
Over the six-month trial period with commercial flights powered with sustainable aviation fuel, Lufthansa completed roughly 1,200 flights on an Airbus A321 aircraft.

At the time, sustainable aviation fuel was not widely available, and the cost difference compared to fossil fuel was high.

“In addition to cost and availability, we were looking for fuel that is not part of the ‘food versus fuel’ dilemma—using farmland or crops for biofuel production to the detriment of food supply—so second-generation biofuels produced from materials such as used cooking oil, municipal waste, and wood waste had to be sourced,” Kleffmann says.

Together, these factors meant Lufthansa was unable to immediately scale up the project. However, both companies wanted to keep talking, and to continue their cooperation as soon as it became feasible.

Taking sustainable fuel to the market
Thankfully, all the hard work paid off. This past October, Neste and Lufthansa Group announced they are strengthening their collaboration. Today, Lufthansa uses sustainable aviation fuel on its flights departing from Frankfurt. These are some of the key points that contributed to Lufthansa’s success.

To make that 2011 trial project happen, Lufthansa and Neste collaborated with a number of universities and industry partners. “It was a huge effort because it was the first time for all of us,” Kleffmann explains, adding that all parties cooperated well throughout.

“Even now, we are still working and pushing supply chains to accept sustainable aviation fuel in their systems and opening up, however it seems that not everybody is ready yet.”

Kleffmann offers an example: Currently, she says, “the NATO pipeline system in use throughout Western Europe doesn’t accept sustainable aviation fuel.” This has posed a challenge beyond the usual distribution questions.

But renewable jet fuel, Kleffmann says, is the most sustainable option on the market today, even compared with electric flight.

“For example,” she says, “If an Airbus 320Neo, fully fueled with kerosene, used the same weight in batteries to fly as an electric aircraft, instead of 7 hours, we could only fly for 20 minutes. Or, another good example is that to compensate for the energy of 1 kilogram of kerosene, you would need 70 kilograms of batteries.”

She also thinks that supplementary use of synthetic aviation fuels such as power-to-liquid fuel (made through using renewable electricity to produce hydrogen from water and carbon dioxide captured from the air) could make carbon-neutral flying possible in as little as 10 years’ time.

In addition, Lufthansa and SWISS customers can offset their carbon emissions through the ’Compensaid’ platform developed by the Lufthansa Innovation Hub—either by investing in sustainable, alternative kerosene or through ‘myclimate’ climate protection projects. Customers can also combine the two options. READ MORE