Aviation is a naturally inventive sector.
Even with the devastating effects of the COVID-19 epidemic, green technology in
aviation is being researched at a higher rate than ever before. Various types
of sustainable aviation fuels are now available for use in airplanes, and new
aircraft technology and operating methods are being developed to reduce CO2.
At different altitudes, aviation has
distinct effects on the Earth’s atmosphere. NOx and halogens affect the ozone
layer at the highest level in the stratosphere; NOx, CO2, H2O, and particulates
affect climate change in the troposphere; and NOx, O2, and particulates affect
local air quality, as well as noise pollution from aircraft entering or
departing from airport terminals and at ground level.
The Concerning Environmental Challenges
Climate change continues to be a major
concern to aviation, and all stakeholders in the industry recognize and
understand the need for quick action. The sector is concerned about ‘flight
shame,’ the enforcement of environmental-related taxes and regulations, and the
rising attention of investors on Environment, Social, and Governance (ESG).
While aviation accounts for only 2.5 percent of global CO2 emissions (much less
than the public’s perception), its route to lowering its carbon footprint is
less evident than that of other industries. The net-zero aim for 2050 is quite
ambitious, and achieving it will be a significant challenge for the industry.
Fleet renewal, operational efficiency
improvements, technical innovation, sustainable aviation fuels (SAF), and, in
the short term, carbon offsetting are all components of lowering emissions.
Some of these technical elements, such as hydrogen or electric-powered
aircraft, are still a long way off from having a significant influence.
Sustainable aviation fuel (SAF) is widely agreed to be the immediate priority,
with IATA predicting that it would be the key driver of emission reductions
over the next decade and beyond. However, the present levels of SAF
availability and its current price, which is more than three times that of jet
fuel, pose significant hurdles. Governments must play an active role in driving
the demand for SAF by providing incentives to attract more manufacturers and
investors to the field.
The International Civil Aviation
Organization (ICAO) launched CORSIA (Carbon Offsetting and Reduction Scheme for
International Aviation) to combat global warming, with the goal of halving CO2
emissions from 2005 levels by 2050. Other programs exist, such as the Air
Transport Action Group (ATAG) waypoint initiative, which aims to cut CO2
emissions in half by 2050, while the European Commission Green Deal mandates
that Europe be carbon neutral by 2050.
Small Steps for Big Change
By the year 2050, the aviation sector has
set a self-imposed aim of reaching net zero carbon emissions. Green
technologies in the industry have begun to emerge as a result of this ambitious
goal. Sustainable aviation fuel is one such technique (SAF). The popularization
of SAFs, out of all the technologies that might potentially bring the aviation
industry closer to its environmental targets, shows the most promise in terms
of impact and efficacy.
- Limiting Contrails
Aviation produces water vapor, aerosols,
and nitrogen oxides in addition to carbon dioxide. Because these pollutants
absorb more energy than is emitted out to space, the Earth’s atmosphere warms.
As a result, aviation’s contribution to global warming may be considerably
greater than its carbon footprint.
Condensation trails, are the line-shaped
clouds that emerge from a plane’s engine exhaust. They are the worst of the
non-carbon consequences. The majority of contrails are caused by a limited
number of planes. This is due to the fact that contrails only form in narrow
atmospheric bands where the weather is sufficiently cold and humid.
Avoiding those zones might make a major
impact in reducing non-carbon emissions from aircraft. According to a study
that modeled Japan’s airspace, changing a small number of flight paths to avoid
certain locations might reduce contrail impacts on the environment by 59%. The
elevation difference between these places might be as minor as 2,000 feet.
While flying a plane higher or lower might degrade efficiency and increase jet
fuel consumption, the study revealed that minimizing contrails would still balance
any increased carbon emissions.
Inventing Fuel Alternatives
Commercial jets utilize kerosene-based
propellants, but firms are experimenting with converting biomasses into jet
fuels, such as vegetable oil and even used diapers. According to some studies,
these biofuels might reduce carbon emissions from airplanes by up to 60%.
However, not all biofuels are made equal.
Because of the planet’s rising population,
which requires crops for calories, those that might be converted into food are
unsustainable. Used cooking oil and pulp from agriculture or logging are both
costly and not generated in high enough quantities to make a significant
impact. However, this does not exclude out the development of other
environmentally friendly aircraft fuels.
- Going Hybrid
Electric vehicles aren’t the only mode of
transportation being developed: according to one estimate, there are over a
hundred electric-powered aircraft projects in the works. From powered gliders
to light aircraft and small electric vertical take-off and landing (eVTOL)
personal air vehicles and air taxis, the potential of electric aircraft has
grown, and the concept is now being actively considered for larger regional
aircraft powered by electric engines or multiple transmission and distribution
In recent years, aircraft propulsion
systems have undergone a revolution, with hybrid-electric and battery-powered
electric aircraft increasingly proving to be a cost-effective alternative to
traditional platforms — at least for smaller, short-range aircraft. Such
airplanes are the ultimate solution to the problem of CO2 reduction since they
emit no (or less) direct carbon emissions (in the case of hybrid-electric
propulsion) (although the generation of the electricity to charge the batteries
may do so).
In order to achieve net zero emissions by 2050, the aviation sector is now pursuing four levers: increasing energy efficiency, utilizing sustainable aviation fuel, developing alternative technologies, and employing carbon offsets. Because jet fuel combustion is responsible for the great majority of airline scope 1 emissions, efforts are being concentrated on upgrading fleets to the most fuel-efficient new technology aircraft and transitioning to the complete usage of sustainable aviation fuel.