Aviation contributes a whopping 2.1% to total global emissions. The International Air Transport Association (IATA) has created a plan to achieve net zero by 2050 using a 4-pronged approach
1) More efficient operating models:
This encourages a comparison between Hub & Spoke (H&S) and Point-to-Point (P2P) models.
Simply put, in the P2P model airlines fly passengers on non-stop flights from the source to the destination. In the H&S model, an airline flies all passengers to their hub airport and then onward to their destination (for hubs think Emirates at Dubai or Iceland air at Reykjavik). It’s essentially a way to collect all passengers at one place and then send them off to their destination.
Example
P2P: Daily direct flights on large aircrafts from multiple Indian cities (Bangalore, Mumbai, Hyderabad, Kolkata etc.) to London
H&S: Smaller aircrafts (say A320) fly passengers to Dubai from multiple Indian cities and then few large aircrafts (say B777) fly to London from Dubai. This significantly improves payload factor (passenger occupancy %).
I unfortunately don’t have any emission data comparing the two models but the H&S seems more efficient for the following reasons:
a) All direct flights (especially on large aircrafts) are very unlikely to have a high payload factor (PLF) i.e. per passenger emissions will be higher.
b) Having a massive hub for your operations presents the opportunity to be relatively asset light as the airline needs to focus its efforts on the hub
The H&S does entail longer routes and flying hours but the higher PLF and economies of scale would likely reduce per capita emissions.
2) More efficient equipment
Fuel efficiency has consistently improved over time. I’ll pick a few popular aircrafts to illustrate this:
As we can see, fuel efficiency has been improving over time. Moreover, groundbreaking technology like electric aircrafts might help reduce emissions at a faster rate.
3) Sustainable aviation fuel (SAF)
SAFs describe nonconventional (not fossil derived) aviation fuel. SAFs are derived from alternative feedstocks such as crude oil, farm wastes, and food wastes. To validly use the term ‘’sustainable’’ they must meet sustainability criteria such as lifecycle carbon emissions reduction, limited fresh-water requirements, no competition with needed food production, and no deforestation.
SAFs are not standardised but some have found to reduce lifecycle CO2 emissions by as much as 80%. More than 50 airlines around the world have experimented with SAF flights.
4) Carbon offsets
The least exciting among all options as it likely does not provide sufficient incentive to reduce emissions. Here is a quick example to illustrate my point:
The Voluntary Aviation offsets add only $1.57 and the more expensive EU Carbon Permits add $25.94 to the airfare which is currently priced around $450 – $750 for BLR-LHR. That’s hardly a disincentive!
The aviation carbon offset program is organised under CORSIA (Carbon Offsetting and Reduction Scheme for International Aviation). CORSIA offsetts the amount of CO2 emissions that cannot be reduced through the use of technological improvements, operational improvements, and sustainable aviation fuels
IATA has set an ambitious target for achieving net zero. Interesting years lie ahead as global aviation kickstarts this massive project.
Sources: IATA, ICAO, carboncredits.com (pricing)