Aviation accounts for nearly 3 percent of the world’s human-caused carbon dioxide emissions, and without urgent action, that share could rise to 22 percent by 2050, the aviation group Energy Transitions Commission said.
Airlines belonging to the International Travel Agents Association (IATA) have already committed to achieving zero net emissions by 2050. This means that the amount of CO2 emitted by airlines is offset by the amount of CO2 emitted by the atmosphere.
The first net-duty flights are already taking off, and some will use sustainable aviation fuel (SAF) and others will offset flight emissions through a reserve and redemption system by purchasing SAF.
Here are three innovations that will help bring sustainable aviation closer.
Sustainable aviation fuels
Replacing kerosene, traditionally used as an aviation fuel, with sustainable alternatives offers significant opportunities to reduce aviation emissions.
Sustainable jet fuels are mostly made from forest or agricultural waste, not fossil fuels, which enables them to reduce airline CO2 emissions by around 70%.
Virgin Atlantic is planning a Boeing 787 demonstration flight from London Heathrow Airport to New York JFK Airport in 2023, which would be the first net duty-free flight in the world. However, safety regulations allow a maximum of 50% SAF mixed with kerosene, so the remaining 30% of in-flight emissions are offset by investments in carbon removal technology.
SAFs are currently much more expensive than kerosene, but increased production could help reduce costs and increase airline adoption.
Other solutions, such as batteries or hydrogen fuel, are also being developed but have not yet been proven at scale.
Open Fan Architecture
The second part of the aviation sustainability agenda calls for a radical rethinking of engine design aircraft.
Unlike traditional stealth aircraft engine blades, new open-fan architecture engines are being developed to increase fuel efficiency and reduce flight emissions.
Removing the blade housing increases flight efficiency because less weight is involved. The open design also allows for the installation of larger fan blades that can move more air around this engine, reducing drag.
GE Aviation and Safran jointly launched an aircraft engine development programme aimed at reducing single-engine aircraft emissions by more than 20% compared to current engines.
Engines with an open-fan architecture compatible with alternative fuels such as SAF and hydrogen may be introduced in the mid-2030s.
The CFM RISE (Revolutionary Innovation for Sustainable Engines) programme is also investigating hybrid electric engine designs that could enable the electrification of several aircraft systems.
New Propulsion Systems
Hybrid electric propulsion has also been incorporated into an entirely new type of aircraft powertrain.
“New propulsion technologies will play an important role in achieving zero aviation goals, along with new aircraft and sustainable energy sources,” said Sabine Klauke, chief technologist at aircraft manufacturer Airbus, Avionics International.
A consortium of aerospace companies, including Airbus, Pratt & Whitney, GKN Aerospace, and Collins Aerospace, joined forces with the University of Stuttgart in the Sustainable Water Spray Turbofan Consisting of Hybrid Electronics (SWITCH) project.
The project combines hybrid electric propulsion with water-enhanced turbofans (WET), which improve flight performance by capturing water vapour from the aircraft’s exhaust and recirculating it back into the engine’s combustion chamber.
Electric motors can help reduce the carbon footprint of flight by improving efficiency during takeoff, airborne flight, and descent, but especially when taxiing on the ground.
Innovation to improve operational efficiency and develop low-carbon solutions is an important part of the aviation industry’s efforts to achieve zero emissions, but more needs to be done.
Politicians, regulators, and business leaders must agree on an action plan to bring about real change, supported by a policy framework that encourages airlines to use more sustainable and low-carbon solutions.
Initiatives, such as the Clean Skies for Tomorrow programme of the World Economic Forum, bring together leaders from industry, government, and civil society to contribute to efforts to reach the goal of zero emissions by 2050.
Source: WEF
