In a workshop along France’s Atlantic shore, aviation trailblazer Bertrand Piccard and his team are intensively working to get ready for a flight that has the potential to revolutionize air travel entirely.
A decade ago, when Piccard led a highly publicized global flight in a solar-powered aircraft, it increased consciousness regarding climate change but offered scant potential for transforming commercial aviation.
Currently, the 66-year-old Swiss explorer who led Solar Impulse is reaching for even greater heights with the ambition to pave the way towards more environmentally friendly commercial flights instead of relying on conventional fossil-fuel-driven aircraft. This time, he plans to utilize extremely cold liquid hydrogen as his power source.
The Climate Impulse initiative commenced last February with the aim of piloting a two-seat aircraft around the world without stopping for refueling within nine days, powered exclusively by so-called green hydrogen.
That's hydrogen extracted from water molecules via a method known as electrolysis, powered by renewable electricity.
This week, the Climate Impulse group, supported by investors such as Airbus and a science accelerator named Syensqo ("science-co"), which emerged from Belgium’s Solvay pharmaceutical firm, shared their initial year achievements with reporters in Les Sables d'Olonne, a coastal community famous for hosting the Vendée Globe around-the-world yacht race.
When is Climate Impulse scheduled to take off?
The initial test flights are scheduled for next year, however, the challenging circumnavigation journey is slated for 2028. Constructed using lightweight composite materials, this aircraft relies heavily on numerous unproven technologies and remains quite uncertain of success.
Piccard states that a leading aircraft company would be unwilling to assume the risk involved in developing a prototype like Climate Impulse, particularly if there's a possibility of failure.
As a trailblazer, it’s my responsibility," he stated during an interview. "Demonstrating that it can be done provides a significant motivation for others to carry on.
Despite success with this project, specialists indicate that widespread commercial green hydrogen-driven flights remain likely several decades out. It has attracted substantial investments amounting to tens of millions of euros, and the expanding workforce now consists of scores of employees.
In 2015, the sun-driven aircraft represented a significant technical achievement; however, it lacked scalability, according to Raphael Dinelli, an engineer at Climate Impulse and one of the co-pilots. Due to its restricted range, this airplane needed over a dozen stopovers for its journey encircling the globe.
Climate Impulse is designed to launch independently, circle the globe for approximately 40,000 kilometers (around 25,000 miles) following the equatorial path, and come back to its origin without requiring any aerial refueling or intermediate landings.
What is the process for flying with Climate Impulse?
The regulated discharge of liquid hydrogen from highly insulated tanks beneath the aircraft’s wings generates power that permeates the membrane of a fuel cell, which then drives the plane.
"The plane has the wingspan of an Airbus 320: 34 m (about 110 ft). It weighs 5-1/2 tons and it flies at 180 km/h — that means 100 knots at 10,000 ft (3,000 m) altitude," Piccard said on Thursday.
The objective includes harnessing power from the "turbulent zone" within the atmosphere, an area that might someday assist aviation companies in reducing their fuel consumption, as mentioned by him.
Since it's hydrogen, the sole emission produced will be water vapor. Nevertheless, external specialists warn that the ecological effect of these water-vapor contrails is still uncertain when considering practical or extensive applications.
According to the International Energy Agency, air travel accounts for approximately 2 percent of worldwide carbon dioxide emissions.
Hydrogen has been utilized in aviation for many years, though typically as a gas rather than a liquid. Transitioning to liquid hydrogen would require considerable time to implement effectively. Currently, fossil fuels remain more economical and efficient, thus they continue to be the primary source of hydrogen production.
Numerous governments aim to increase the production of green hydrogen, yet currently, the global capacity for generating sufficient clean electricity for terrestrial demands remains inadequate. This challenge becomes even more pronounced when considering the substantial requirements needed to support widespread usage by aircraft in flight.
What happens next?
Over the past year, the team has constructed the cockpit shell, initiated work on the wing spar, and completed various internal elements. These features encompass pivoting seats, a sleeping berth, and an exercise device similar to a stationary bike designed to enhance blood flow for the co-pilots during their nine-day confinement in a confined space with limited oxygen levels.
The hardest parts await.
This year will see tests conducted on the fuel cells and propulsion systems to determine whether the electric motor, propeller, and batteries can be utilized for an initial phase of completely electrified flights.
Dinelli mentioned that the most challenging aspect is controlling the flow of liquid hydrogen to maximize efficiency and extend the vehicle’s range as much as possible.
A further hurdle is maintaining the liquid hydrogen at -253 degrees Celsius (-423 Fahrenheit), which is almost absolute zero. It’s crucial to build a tank that is entirely free from leaks.
Hydrogen liquid can easily ignite; therefore, even slight leakage might lead to severe consequences.
Does green hydrogen-fueled aviation have a future?
Up until now, liquid hydrogen may have most notably served as a fuel to launch rockets into space.
The aviation sector contributes a modest portion of total carbon emissions; however, this contribution is increasing more rapidly than in any other industry. This growth outpaces advancements seen with electric vehicles like cars and trucks on land, where such technologies have developed much quicker.
The batteries used in electric vehicles on the road today are quite heavy, and reducing battery weight in aircraft will be essential for successful electric-powered aviation.
"There hasn't been an 'Aviation Tesla' moment yet," stated Nikhil Sachdeva, a specialist in helping the aviation industry shift towards more environmentally friendly technologies at consultancy firm Roland Berger.
Hydrogen holds the promise of being the solution for aviation, which is precisely why getting this right is crucial.
Utilizing extremely cold liquid hydrogen is "incredibly challenging, and currently we can only manage it for a few minutes at a time. We're discussing making it safe for operation over several hours," according to Sachdeva.
However, Solar Impulse also encountered skepticism, he noted, and Piccard's group has shown that they can achieve what others might see as unattainable.
