Decarbonizing aviation: 5 ways to soar into a cleaner future

The aviation sector accounts for ~2.5% of GHG emissions, but its contribution is expected to increase more than the transportation sector. The aviation industry is estimated to be directly responsible for creating a 0.1 °C increase in global temperature by 2050 if serious measures are not taken. Facing increasing pressures in the context of decarbonizing the global economy, the aviation industry took a decisive step in 2021 by committing to achieve net-zero CO2 emissions by 2050. However, geographical spread, technological diversity and scale of operations make the aviation especially hard to decarbonise.

In this article we identify five primary solutions: Sustainable Aviation Fuels (SAFs), Hydrogen fuel, Electric propulsion, Offsets and Carbon capture, and Responsible decommissioning of aircraft. Yet, any decarbonisation solution proposed in the sector must adhere to the stringent specifications, standards and compliance requirements. 

Sustainable Aviation Fuels (SAFs)

Sustainable Aviation Fuels (SAFs), derived from renewable sources such as algae, jatropha, and waste byproducts, offer a promising solution to the aviation industry's carbon emissions challenge. With the potential to reduce up to 80% of CO2 and particulate emissions compared to conventional jet fuels, SAFs can contribute to a more sustainable future. With net-zero 2050 as the target, Bio-SAF is expected to lead the shift away from traditional aviation fuels (CAF). Bio-SAF’s share in fuel consumption should be increased from 5% by the end of this decade to about 50% in 2050. Moreover, power-to-liquid SAF (PtL or e-fuels), manufactured using clean energy and carbon dioxide, will become important starting in 2040 and is expected to cater to one-third of the total in-flight energy consumption for the aviation industry by 2050. 

However, significant challenges persist. SAFs are currently priced higher (about 2 times) for the same energy content as traditional jet fuels and still contribute to non-CO2 emissions. Nevertheless, by integrating SAFs into existing aircraft and fuel systems, the industry can rapidly adopt this relatively cleaner alternative. SAF costs may fall as higher production levels bring economies of scale. A rapid and cost-effective pathway to promote the adoption of Sustainable Aviation Fuel (SAF) lies in co-processing, a method of producing SAF by integrating bio-based intermediates with petroleum feedstocks in existing refineries. Europe, North America, and Asia Pacific are poised to lead in SAF production through co-processing, with potential output reaching 2.6 million metric tons annually by 2030 and a potential to reach 34 million metric tons by 2050. The costs associated with this transition are expected to be USD 1.4 billion by the end of 2025 and USD 33 billion by 2030. Additionally, advancements in engine technology can further optimize performance and reduce non-CO2 emissions, such as NOx and particulate matter.

Hydrogen fuel

While Sustainable Aviation Fuels (SAFs) provide a near-term and partial solution to reduce aviation's carbon footprint, they are not a definitive long-term answer. Green Hydrogen (GH2), with its potential for zero-emission flights, is the true north star. GH2-based technologies can be primarily classified as hybrid hydrogen-electric fuel cells or direct hydrogen combustion. Both are promising and complex and require substantial re-design of an aircraft’s systems and ground-based infrastructure for commercial aircraft adaptation.

Adhering to the highest safety standards in GH2 manufacturing, transport, storage and utilisation in the air and on the ground are critical to building trust in this technology. The GH2 for aircraft transition cost is expected to be USD 0.2 trillion for 2030-2050. Thus, government and private sector collaboration is essential to develop bankable GH2 technologies rapidly. Developing airports as ‘GH2 Hubs’ can unify the ecosystem needs, comprising aircraft, ground support vehicles, heat and power for catering and airport operations, etc. Signing GH2 purchase agreements with local manufacturers can ensure a reliable supply chain to meet the sector’s growing and diversified demand. 

Electric propulsion

Aviation electrification presents a promising avenue towards a more sustainable future for the industry. Electric vertical take-off and landing (VTOL) aircraft offer quiet, efficient, convenient and zero-emissions travel options, especially for intracity and short-haul intercity transport. To rapidly commercialise this technology, tailored offerings for general aviation for the business/leisure segments, especially in island regions, city-patrolling by law enforcement agencies and air ambulances can be considered a priority. Developing long-haul electric flights is a multi-decade endeavour. Here, solar aircraft that leverage the synergy between rechargeable energy storage systems, high-efficiency photovoltaic cells, improvement in fuel cells, lightweight materials, power management software and aircraft-design provide an interesting alternative to conventional aircraft.

Offsets and carbon capture

The aviation industry can only fuel its ever-growing operations through carbon-emitting fuels. While SAFs (biobased and e-fuels), GH2 and electrification can substantially cut down in-flight emissions, it is important to note that the airline industry ecosystem still emits greenhouse gases (GHG). All stakeholders in the airline industry, including aircraft manufacturers, airlines, fuel producers, airport operators, etc., must be mandated to offset their emissions through nature-based solutions, direct-air capture and carbon capture utilisation and storage. A fair share of these costs can be passed on to the passengers through an equitable ticket pricing structure. All such emission reductions must be accurately quantified while complying with globally accepted protocols and must be regularly audited and publicly disclosed. 

Responsible for decommissioning of aircraft 

About 700 aircraft reach end-of-life each year, which is expected to increase. The global commercial aircraft disassembly, dismantling and recycling market size is projected to grow from USD 8 billion in 2023 to USD 15 billion in the next 10 years. Successfully decommissioning and recycling aircraft requires a multidisciplinary approach and strong collaboration among various stakeholders. By working together, industry players can optimize the remanufacturing process and ensure compliance with stringent environmental regulations, such as the European Union's End-of-Life Vehicle (ELV) directive. This proactive approach contributes to sustainable practices, favourably positions the aviation industry for future regulatory challenges, and generates local employment opportunities.

The aviation industry increasingly serves as the lifeblood of our global economy. Hence, a synchronised approach can ensure that countries at different stages of development with diverse resources and financial capabilities can work in tandem to meet aviation’s ambitions for decarbonisation. 

Check Data Hub™ for the sustainability performance of the world's most polluting companies in the aviation sector: Ryanair (14 million metric tons of CO₂ per year), Lufthansa (27 mtCO₂), IAG (25 mtCO₂), EasyJet (7.5 mtCO₂), Wizz Air, and Air France.

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