The results were determined using Cirium's EmeraldSky methodology, which uses CO2/ASK (available seat kilometer) as the primary metric. This standard reflects CO2 emissions per seat provided per kilometer flown. According to the report, Vietjet's emission level was 64,5 grams of CO2/ASK. Singapore Airlines followed with 66,7 grams, and Lion Air with 67,1 grams. The report also indicated that airlines with younger fleets and higher seat density consistently lead the market.
The ranking compares emission levels on flights within Southeast Asia, a region where the prevalence of short and medium-haul routes makes fuel optimization more challenging.
Maintaining the lowest emission level demonstrates the airline's operational optimization capability across its entire operational chain, from aircraft configuration and route network organization to payload management.
The airline currently operates mainly Airbus A320 and A321 aircraft, including "NEO" versions that save about 15-20% more fuel compared to the previous generation. With one of the youngest fleets in the region, Vietjet significantly optimizes fuel consumption and CO2 emissions per flight. Alongside fleet investment, the airline enhances technology application in operations, from flight data analysis platforms like SkyBreathe to fuel optimization cooperation programs like SFCO2, thereby improving operational efficiency across the entire system.
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A Vietjet aircraft. Photo: Tai Nguyen |
Previously, AirlineRatings honored Vietjet among the top 7 global sustainable airlines for 2025 due to its efforts in emission reduction, efficient fuel use, and green aviation development. The airline also received recognition for its ESG (environmental, social, and governance) performance in markets such as Taiwan (China).
The Flight Emissions Review is Cirium's annual ranking, independently assessing the 100 largest airlines worldwide based on actual operational data. It allows for comparing emission levels among airlines by operational scale and geographical region, providing a transparent benchmark for the industry.
Thai Anh
