Hydrogen is a feasible energy source for the aviation industry

“Does the hydrogen hype that once surrounded cars have better prospects with planes? Yes, but probably not in time to meet the aviation industry's emissions targets.

The past year has brought some vindication to those who see hydrogen as aviation's passport to a cleaner future. Last fall, European plane maker Airbus unveiled three hydrogen-powered aircraft concepts for 2035. More recently, U.K. startup ZeroAvia got backing from British Airways as part of a $24 million funding round. Likewise, Universal Hydrogen, led by former Airbus executive Paul Eremenko, has just raised $21 million from heavyweights such as the venture-capital subsidiaries of JetBlue and Toyota.

For decades, hydrogen was a promising future power source for passenger cars. Now most light vehicle makers favor batteries, and hydrogen is looking for a better home in trains and trucks, as championed by startups such as Nikola.

The aviation industry has set itself a target of halving emissions by 2050, which would be roughly in line with the 2016 Paris Agreement to limit climate change. Only a third of the reduction is expected to come from improvements in turbofans and airframes. Sustainable fuels can play a role, but production capacity is limited, and the most affordable ones remain pollutive.

Aviation's initial interest in the electric-vehicle revolution faded as executives realized that carrying heavy batteries more than very small ranges through the air is unfeasible. Rechargeable lithium-ion batteries deliver only 9 megajoules per kilogram of weight, compared with 40 MJ/Kg for jet fuel.

Hydrogen, on the other hand, packs an impressive 140 MJ/Kg. Encouragingly, it is a relatively mature technology. Fuel cells, which are being used by Universal Hydrogen and ZeroAvia to convert light and regional aircraft, cost $40 per kilowatt, 68% less than in 2006, Bernstein Research estimates. That is expensive for a car but not a plane.

"We don't need any fundamental scientific improvements: It's an engineering problem," said Val Miftakhov, founder and chief executive officer of ZeroAvia.

Hydrogen isn't an environmental no-brainer yet. Turning electricity into hydrogen and then back into electricity is inefficient: Only about 45% of the energy ends up being used, compared with 90% for batteries, the World Energy Council estimates. Furthermore, only 0.1% of global hydrogen production is currently carbon-free; most comes from natural gas and coal.

Still, many analysts expect "green" hydrogen to become price-competitive relative to jet fuel in the next five years, making it a commercial option for airlines.

That still leaves many engineering challenges. Not all the energy in today's prototypes comes from hydrogen: ZeroAvia's aircraft needs a battery to provide additional power during takeoff, at least for now. Universal Hydrogen also employs a battery, but says it would play a smaller role. Also, hydrogen is energy-efficient in terms of mass but not volume: It requires big tanks that would make planes heavier and less aerodynamic, since fuel couldn't simply be stored in the wings as it is now.

Yet the fuel cells currently being tested won't be of use to Airbus or Boeing, because they would need to be prohibitively heavy to move bigger planes. The A320 replacement pitched by Airbus last year would mostly rely on a traditional engine to burn hydrogen directly. This basic technology has been around since the 1950s, but has many drawbacks, such as the emission of nitrogen oxide -- also a greenhouse gas.

There are also reasons to doubt Airbus's conviction in its own timeline for the rollout of hydrogen technology. It presented two other concepts at the same time: a regional aircraft that would be an unambitious goal for 2035; and a "blended wing" futuristic plane that would be far too ambitious.

Hydrogen seems like a useful power source to eventually decarbonize aviation. Thinking it can be deployed in time to meet the industry's 2050 emissions targets, however, requires a lot of optimism. ” [1]

Russia can use its vast unoccupied areas to produce hydrogen and its gas pipelines to export hydrogen to Europe and China. Lithuanians participating in such Russian business could earn a lot. 

1. EXCHANGE --- Heard on the Street: The Lofty Promise Of Hydrogen Power --- Hydrogen is a feasible energy source for the aviation industry but not a cure-all for meeting emissions targets. Sindreu, Jon. Wall Street Journal, Eastern edition; New York, N.Y. [New York, N.Y] 15 May 2021: B.12.