Air travel’s green future: Flying cars, electric planes, new fuels

Switching to Sustainable Aviation Fuels is not the only way for the sector to go green. Even as we speak, disruptive emission-killing green technologies are taking shape. We scan the skies to see what’s on the horizon.

Green fuels, flights, airlines
Expanding horizons in technology are ushering in a new era of flying. Image: Pexels/Pixabay.

Picture this. You leave from your workplace and head to the roof of your office building. Just tap on your smartphone and your electric flying taxi is here. Sounds like a scene from the American animated sitcom The Jetsons? The 60-year-old green dream is now actually coming true.

Hover 1
Flying taxis just could soon take off and land vertically as easily as this bird. Image: Pexels/Skyler Ewing

An eye-popping 100 global projects are focussed on Urban Air Mobility. Google’s Kitty Hawk, Uber’s Elevate, and Lilium Jet — all have Vertical Take-off and Landing (VTOL) offerings at various stages of development, suitable for the air-taxi application. Interestingly, Joby Aviation took over Uber’s air taxi in December 2020, and the transport aggregator has invested $125 million in the aviation start-up. Uber plans to offer Joby’s five-seater flights through its ride-hailing app. Joby Aviation has signed an agreement with two real estate companies, Neighborhood Property Group and Reef Technology, to allow rooftop access to Reef’s 5,000 parking garages in the US and Europe. Full electrification, or 100 per cent battery-powered planes are seen to be the future of short- and medium-haul air travel.

Moving to larger capacity planes, EasyJet and Wright Electric are developing a 186-seat plane with a range of 300 nautical miles that could be commercialised in 2030. Last year, British Airways announced a partnership with ZeroAvia to pave the way for a move into zero-emission flights. EasyJet hopes to start operating battery-powered planes by 2027.

Conceptually, solid-state batteries have been demonstrated to have high-energy density, but their commercialisation could be decades today. What hurts the cause of fully electric high-capacity long haul planes is that batteries weigh the same at take-off and landing, whereas, conventionally fuelled planes lose weight as the flight progresses.

To address the challenges with 100 per cent electrification, Boeing and NASA are developing the hybrid ‘SUGAR Volt’2, where the engines were designed to burn fuel when power requirement is high (such as during take-off) and to use electricity while cruising. The summary is a compromise between the reliability of conventional fuel and the green credentials of battery power.

Green fuels, flights, airlines
Did you know that hydrogen fuel cell propulsion can reduce aviation’s climate impact by 75-90 per cent? Image: Shutterstock/stockvit.

Airbus is working to launch hydrogen-powered aircraft by 2035. And then, by 2024, US start-up ZeroAvia plans to build 10- to 20-seater planes that will be powered by hydrogen fuel cells. A fully electric flight today is limited to a short-range 30-240 km. A hydrogen fuel cell propulsion system can expand the range three to five times. What sweetens the deal is that hydrogen fuel cells can be refuelled at a pump in five to 10 minutes, while batteries need 30-45 minutes of charging. Hydrogen fuel cell propulsion can reduce aviation’s climate impact by 75-90 per cent.

Not surprisingly, Etihad Airways is also a part of the aviation fuel working group under the Abu Dhabi Hydrogen Alliance, which is looking at the production of synthetic aviation fuel through Green Hydrogen and Carbon Dioxide capture.

Hydrogen-based fuel solutions certainly hold promise. But the trade-off is that numerous safety concerns must be factored. Besides, considerable investments must be made towards re-engineering of storage and handling and voluminous tanks that must fit into aircraft.

Low-hanging fruit

If hydrogen-powered or fully electrified planes are too much in the future, technology is already helping to curb emissions here and now. 

Airlines are being careful to purchase more fuelefficient aircraft. Image: Pexels/Rakicevic Nenad.

The easiest way to do this is to buy new, more fuel-efficient planes. According to Airbus, CO2 emissions from newly built planes are 80 per cent lower than those developed four or five decades ago. Rival Boeing claims that the 787 Dreamliner is 20 per cent more fuel-efficient per passenger relative to older aircrafts. Airlines like JetBlue, Jetstar, and Qantas seem to have bought into this logic. They have expanded their fleet in recent times.

Goh Choon Phong, Chief Executive Officer, Singapore Airlines, says, “Today, the most effective and direct way for an airline to materially lower carbon emissions is by operating a young fleet of aircraft. The SIA Group’s fleet has an average age of under six years, making it one of the youngest in the world. Over the last year, we have retired 45 older aircraft. We will be gradually replacing them with new-generation aircraft that are up to 30 per cent more fuel efficient and will substantially lower our emissions in coming years.”

India’s Indigo Airlines has replaced 25 of its A320 Ceo with the more fuel-efficient A320 Neo planes so far and plans to induct at least 20-25 A321 planes during FY 2022. These new additions are expected to reduce operating costs by 15 per cent. Modernising the fleet is surely useful but is capital-intensive. So, airlines continually work upon optimisation of existing planes and technologies supporting their operation. Artificial Intelligence (AI) is coming to the fore. Carriers such as Air France and Norwegian Airlines have signed up to use Sky Breathe, an AI technology that analyses flight operations to reduce fuel consumption.

Technology is helping to save the planet. Artificial intelligence and apps come to the rescue! Image: Shutterstock/cottonbro.

Elsewhere, Alaska Airlines has saved 1.8 million litres of fuel in six months and reduced 4,600 tons of carbon emissions. The airline, which operations in harsh arctic conditions, uses an AI-enabled dynamic mapping system. It offers a fully dynamic, real-time ‘4D’ map with relevant information in one, easy-to-understand screen. The information presented includes Federal Aviation Administration (FAA) data feeds, turbulence reports, and weather reports, which are all visible on a single, highly detailed map. The system also affords the promising ability to scroll forward more than eight hours into the future, helping to identify potential issues with weather or congestion.

SIA also uses AI to reduce fuel consumption. Besides, it has partnered with Lumitics, a Singapore-based food waste management start-up, to co-develop a cutting-edge digital solution, which can cut food waste. Staying on food, the airline has introduced bio-degradable food and beverage packaging that also considerably reduce cabin weight, thereby saving fuel and curbing emissions. Singapore’s national carrier has also invested in engineering improvement packages for airframes and engines, which help to reduce drag and improve engine efficiency. For the same reasons, it offers digital newspapers, magazines, in-flight menus, and shopping catalogues.

Rationalising demand for fossil fuels

Some European countries are contemplating a move to make frequent flyers pay a ‘green tax’. Others are trying to dissuade short-haul flights between busy airports that involve fuel-guzzling taxiing. Most of these cities are well-served by high-speed railway networks.

And flyers seem to agree. They are choosing to take longer direct flights and increasingly flying economy. There is also a preference for newer aircraft. Domestic flights are being dispensed with for rail. And, where possible, the eco-conscious passenger flies during the day to reduce the effects of contrails.

Travel services aggregator Skyscanner polled 5,000 people across the UK, US, Australia, Germany, and South Korea. More than a third of respondents from the UK said that sustainable travel was more important to them now than it was before the pandemic. The same poll also showed that nearly 45 per cent of UK respondents would be more likely to fly with an airline if it was using or investing in greener fuel options.

More and more evolved travellers are conscious about their carbon footprint and prefer to pick an airline that is trying to protect the environment. Image: Pexels/Cosmindoro.

Lufthansa’s Compensaid platform enables passengers to track their CO2 emissions and offset them by buying sustainable aviation fuel. Swiss Air also has a partnership with Compensaid and United Airlines to enable passengers to support the SAF cause.

The airline sector is clearly exploring all avenues to find green alternatives. Responsible travel may begin with the passenger, but the journey is being shared by all the stakeholders.

Read more.

Green fuels: Not just a flight of fancy

How international airlines such as Virgin Atlantic and Qatar Airways are reinventing the wheel

Rolls Royce begins constructing the world’s largest aircraft engine