Navigating a path to net-zero aviation
The aviation industry has shown that net zero flight is theoretically within reach. What will it take to make it a commercial reality?
On 16 November 2022, flight EY130 departed Washington Dulles airport and embarked on a seemingly regular, non-stop, 12 hours and 40-minute flight to Abu Dhabi. But EY130 was anything but regular.
The latest in a series of experimental “EcoFlights” conducted by the national carrier of the United Arab Emirates, Etihad Airways, was groundbreaking in several ways. A partnership with World Energy, a carbon net-zero solutions provider, flight EY130 was the first to achieve net zero using a unique combination of direct emissions reductions and World Energy’s Sustainable Aviation Fuel Book & Claim system.
The partnership reduced EY130’s CO2 emissions by 250 metric tonnes, by replacing approximately 26,000 gallons of petroleum-based jet fuel with World Energy’s net zero equivalent sustainable aviation fuel (SAF) at Los Angeles International Airport (LAX).
World Energy is spending US$4bn to increase the production of SAF, which is certified as compatible with existing jet engines, to more than 500mn gallons by 2025, and 1bn gallons by 2030.
Book & Claim
“This flight proved that Book & Claim is the only feasible path to net zero commercial aviation using current technology, and is the transition framework required until the supply of sustainable aviation fuel reaches its maturity and availability," explains Mariam Alqubaisi, Etihad Airways’ Head of Sustainability & Business Excellence.
World Energy’s Sustainable Aviation Fuel Book & Claim system works by allowing airlines to purchase SAF, which it then delivers to the main fuel supply tanks at LAX. The SAF is then mixed with standard aviation fuel and distributed to aircraft when they refuel at the airport, increasing the overall amount of SAF in circulation rather than delivering it directly to a specific flight. World Energy then register the purchase of the SAF, and its equivalent emission reduction claim, in the Roundtable on Sustainable Biomaterials Book & Claim Registry.
A collaboration of more than 60 stakeholders across academia, business, NGOs, governments and the United Nations, the Roundtable on Sustainable Biomaterials (RSB) operates as a global sustainability certification system for all biomaterials.
Book & Claim relies on a chain-of-custody model that enables the purchase of SAF, and its associated environmental benefits, to be decoupled from its physical consumption, an already proven technique in the renewable electricity sector. Ownership of the SAF and its associated environmental benefits is then transferred to the purchaser using Sustainable Aviation Fuel Certificates, which provide evidence of ownership while covering direct emissions benefits – known as Scope 1 emissions – and indirect emissions benefits, or Scope 3.
“The Etihad and World Energy net zero flight is an exciting example of industry applying concepts from the Clean Skies for Tomorrow Coalition, like the SAF certificate (SAFc) programme,” says Laia Barbarà, who leads the World Economic Forum's aviation decarbonisation efforts. “SAFc makes net zero aviation possible today, flying on sustainable aviation fuels.”
In the case of SAF, the RSB provides third-party oversight to ensure that there is full traceability for SAF and no risk of double-counting, both of which are essential for ensuring the credibility of the Book & Claim process. RSB is also working with Etihad and World Energy to include flight EY130 in the RSB Book & Claim Manual as an official pilot case study.
Next steps
Although SAF is recognised as a valid option for mitigating aviation emissions by the Science Based Targets initiative – a partnership between CDP Worldwide, the UN Global Compact, the World Resources Institute and the Worldwide Fund for Nature – the challenges of cost, scale and distribution remain.
If Etihad Airways had wanted to access World Energy’s SAF directly, the fuel would have to have been transported from LAX to Dulles by tanker, which would incur additional and prohibitive environmental and financial costs. The fact that SAF can only be blended with conventional jet fuel to a 50/50 mix adds a further complication – no flight could rely solely on SAF – which means that the only workable SAF option is to use a Book & Claim system to offset total emissions.
“Our latest flight further validates our commitment but equally shines a light on how much further we all need to go,” Alqubaisi says. “Net zero commercial aviation is possible, but we have to be honest as an industry and say that there are significant logistical challenges to using SAF at present.”
