Today, the biggest barrier is the price of sustainable aviation fuel (SAF), which is still higher than substantial carbon-pricing obligations. This may, however, represent an opportunity for the Polish aviation sector: investments in local SAF production—and potentially hydrogen, as seen for example in Turkey, where it is part of the national carriers’ development strategy. The CPK (Central Transport Hub) could become Poland’s response to the projected 52% increase in air traffic in Europe by 2050. It’s also worth noting the European context: more than 50% of passengers in the EU fly on domestic routes or within the EU-27.
Aviation – a foundation of the global economy
Since 1970, the total number of kilometres flown annually has increased nearly sevenfold, as air travel has become the backbone of globalization, tourism and trade. The global commercial fleet grew from 14,000 aircraft at the beginning of the 21st century to around 30,300 active aircraft registered in mid-2025.
Aviation – the right to mobility, not a privilege
Even more striking than the number of aircraft or kilometres flown is the thirteen-fold increase in the number of passengers since 1970. This marks a structural shift: from aviation as a privilege of the few to a mass-transport system serving billions of people each year.
Massification also means greater environmental pressure
Aviation accounts for around 6% of the emissions contributing to global warming—not the dominant share, but certainly a significant one.
But progress has been made: a 66% reduction in CO₂ per aircraft-kilometre since 1970
The expansion of aviation occurred alongside major improvements in energy efficiency. Emissions per kilometre flown have dropped by about 66% since 1970, reflecting technological advancements in aircraft design, engine performance, air-traffic management and operational practices.
Modern aircraft now use roughly one-third the fuel per passenger-kilometre compared with aircraft from the 1970s. This decoupling of traffic growth from emissions intensity demonstrates continuous improvement.
Yet progress is not fast enough to counter rising demand
Although each kilometre flown emits much less CO₂, the rapid increase in flights, routes and passenger numbers has pushed total emissions to record levels. As a result, the aviation sector’s carbon footprint continues to grow—even as it becomes cleaner per unit of output. Since 1970, aviation-related emissions have increased by 182%.
Demand is rising—but will accessibility fall?
More than 50% of EU passengers fly on domestic or intra-EU-27 routes.
Demand growth
The number of air passengers increased from 0.4 billion in 1970 to nearly 5 billion in 2025. Global demand is projected to reach 12.4 billion by 2050.
Europe will grow more moderately—from 1.19 billion passengers in 2023 to 1.81 billion in 2050—but even this 52% increase poses a substantial challenge to achieving net-zero emissions.
Short-haul flights offer the clearest opportunity for emission reduction:
- routes under 300 km account for 19% of domestic travel
- routes under 500 km represent 45%
According to Allianz Trade, rail could replace air transport on many of these routes, but this requires extensive upgrades. Europe plans to expand its high- and very-high-speed rail network from 12,000 km today to almost 49,400 km by 2050, requiring more than €890 billion in investment.
Complementary measures—such as aviation taxes that reduce intra-EEA demand by roughly 9%—could further accelerate a fair and effective modal shift.
Aviation remains essential to the global economy
It reduces distances, accelerates the movement of people and goods, and supports tourism and trade. But it is also one of the hardest sectors to decarbonize by 2050.
In 2023, aviation produced around 1 gigaton of CO₂, or approximately 2.5% of global anthropogenic emissions (including land-use change). When non-CO₂ effects—contrails, NOₓ, and water vapour—are factored in, aviation’s contribution to global warming rises to about 6%.
Reducing emissions requires a comprehensive toolkit
This includes technologies, fuels, operations and policy. Allianz Trade identifies sustainable aviation fuels (SAF) as the central pillar: they can reduce CO₂ emissions by 60–90% and are compatible with today’s fleet.
However:
- In 2024, SAF supplied only 0.3% of global jet-fuel demand.
- The bottlenecks include limited sustainable feedstock, high production costs and slow infrastructure deployment.
Scaling SAF requires massive investment in renewable energy, diversified feedstocks and large-scale production plants, supported by stable policy frameworks.
But SAF alone cannot deliver full climate neutrality. Non-CO₂ impacts remain substantial. Thus SAF is essential, but must be complemented by broader technological, operational and regulatory tools.
Efficiency improvements
Measures such as retiring older aircraft, adopting more aerodynamic and fuel-efficient models, reducing cabin weight and implementing electric taxiing all reduce fuel use.
Future propulsion technologies
Hydrogen aircraft, battery-electric aircraft and hybrid-electric systems offer long-term transformative potential but require major advances in infrastructure and energy systems.
Market mechanisms also help close the carbon gap
CORSIA
Costs may rise to around $100 per ton of CO₂ by 2027, generating a financial burden of up to $9.5 billion (26% of net sector profits).
EU ETS
Much stricter than CORSIA: airlines must purchase allowances, with demand expected to reach 70 million allowances by 2030 at €80–150 per ton, translating into €5.6–10 billion in costs.
Carbon credits are still cheaper than SAF adoption, but their cumulative cost will grow, affecting margins and fares.
These mechanisms are transitional tools—they offset unavoidable emissions while incentivizing long-term investment in SAF and low-carbon technology.
Decarbonizing aviation requires massive investment: $5.1 trillion by 2050
Allocation of investment:
- 40% – renewable energy for synthetic-fuel production and future hydrogen/electric aircraft
- 38% – expanding SAF production
- 16% – CO₂ capture and electrolysers
- 6% – next-generation aircraft
Without mitigation, aviation would face almost $8 trillion in cumulative carbon-cost exposure.
The transition pathway reduces this to $2.6 trillion and eliminates carbon-price exposure after 2045.
Fleet modernization is essential
With a global retirement rate of only 1.7% in 2024 and a renewal rate of 3.7%, the average aircraft age has reached a record 15 years. Order backlogs of 17,000 aircraft have extended delivery times from 2–3 years to nearly 6.
Upgrading older aircraft (cabin modifications, avionics, engines, aerodynamics such as winglets) offers short-term gains—winglets alone have saved 100 million tons of CO₂ since 2000.
But deep decarbonization requires new aircraft.
Current technology could reduce fuel burn and emissions by around 20% by 2050, but only if manufacturers accelerate production, diversify suppliers, streamline certification and secure government support.
OEMs are investing in SAF-compatible platforms, hybrid-electric and hydrogen propulsion, and advanced aerodynamics. However, R&D spending remains low at 3–5% of revenue.
Achieving net-zero objectives requires significantly higher investment and rapid deployment of efficient next-generation aircraft.
Table: Sustainable Aviation Fuels – Key Benefits and Challenges
(Translated faithfully; table preserved in text form)
| SAF type | Feedstock & production process | Key advantages | Main challenges | Technology & market readiness (2025) |
|---|---|---|---|---|
| HEFA-SPK | Hydrotreating of lipid feedstocks (vegetable oils, used cooking oil, animal fats, tall oils). | Most mature SAF pathway; up to 80% GHG reduction; high compatibility. | Limited sustainable feedstock; competition with food/biodiesel sectors; high hydrogen demand. | TRL 9; 50% blend limit; ~2–3× cost of fossil jet fuel. |
| FT-SPK / FT-SPK-A | Gasification of biomass, MSW or natural gas → syngas → Fischer-Tropsch synthesis. | No sulfur; high thermal stability; flexible feedstocks; up to 90% GHG reduction. | Capital-intensive; large-scale plants required; complex gas cleaning; <60% carbon efficiency without CCUS. | TRL 8–9; 50% blend; PtL-compatible. |
| SIP / HFS-SIP | Fermentation of sugars using engineered microorganisms. | Renewable biochemical pathway; low freeze point; clean burn. | High-cost sugar feedstock; land-use impacts; limited scalability. | TRL 7–8; 10% blend; most production paused for economic reasons. |
| ATJ-SPK | Conversion of ethanol/isobutanol/methanol into jet fuel. | Flexible feedstocks; uses existing ethanol infrastructure; 60–85% GHG reduction. | High conversion costs; needs low-carbon feedstock; catalyst optimization ongoing. | TRL 8–9; 50% blend; scaling 2026–2030. |
| PtL / e-SAF | Renewable hydrogen + captured CO₂ → synthetic hydrocarbons. | Near-zero lifecycle emissions; compatible with existing infrastructure. | Highly energy-intensive; costly renewable H₂ and CO₂; limited demo scale. | TRL 6–8; 50% blend; core of ReFuelEU mandates. |
| Algal oils (HAO-SPK) | Microalgae cultivation → lipid extraction → hydrotreating. | Very high theoretical yields; non-arable land use; strong CO₂ uptake potential. | High energy & nutrient demand; costly cultivation; scaling challenges. | TRL 5–7; pilot/demo stage; no ASTM approval yet. |
