On September 24th, sustainable aviation startup ZeroAvia completed the first fully hydrogen-fueled flight of a commercial-grade aircraft, a six-seater Piper Malibu modified with a 300-kilowatt (kW) battery electric power system, leaving ‘only’ water and heat. Just a few days earlier, Airbus unveiled three climate neutral zero-emission commercial aircraft concepts that ‘use’ hydrogen as their primary fuel source to be put into service by 2035. Using a modified gas-turbine engine that runs hydrogen on combustion, the company states that these planes will have a range of nearly 4,000 kilometer and transport up to 200 passengers.
It is, however, far from clear if hydrogen will win the (full) race for the next generation of aviation fuel. Although it weighs less than kerosene, it has also about four times its volume. Compressing it or putting it into a liquid form asks for complex, heavy and/or large storage tanks. On top of that, the production of hydrogen has to be upscaled substantially, its costs brought down radically and start to use much more sustainable sources that the present meagre one percent. These are crucial challenges that, for example, convince Rolls Royce Aerospace to put its money on sustainable aviation (bio)fuels, which can already be combined with conventional jet fuels to use in current combustion engines. At the same time, a wide range of emerging initiatives across the world invest in the development and production of all kinds of ‘power to liquid’ synthetic electro-fuels, of which hydrogen can also be a major part.
Once again infrastructure may be the deciding factor in picking the winner. Given huge investments in storage capacity at all airports around the world that are required for new aviation fuels, there may in the end only be place for one dominant fuel. The attractiveness of these investments also depends on how much the airline industry is expected to grow in the next decades. The Covid pandemic has clearly lowered those expectation while climate change also play a role as airplanes produce contrails that are responsible for at least half of aviation’s contribution to climate problems. The rise of sustainable fuels that use existing engines and storage capacity on the one hand as well as investments in new infrastructure on the other hand are among the key early indicators to monitor carefully.
Read more on the BBC website - The hydrogen revolution in the skies
Photo by Airbus