Thread by @AIAZero

The insight report on sustainable battery and hydrogen-powered flight we produced in collaboration with @wef outlines 8 unlocks that would enable novel technologies to accelerate #netzeroflight

🧵 Here is a summary of these unlocks:

1⃣ Aviation batteries must be charged with #lowcarbon electricity to ensure reduced emissions. To achieve this, airports could store #renewableenergy to avoid depending on the grid or batteries could be swapped in and out of aircraft to increase charging flexibility.

2⃣ While green hydrogen is a viable aviation fuel, care must be taken if blue hydrogen is to be used in aviation, as its production might result in significant #CO2 emissions and methane leaks that offset emissions savings made in-flight.

3⃣ It is critical to optimise the number of cycles aviation batteries can complete to reduce lifecycle emissions, as well as to prolong their useful life by finding on-ground applications for them once their performance drops below the acceptable threshold for aviation.

4⃣ The range of battery-electric #aircraft using today's batteries is in the region of 300 km, with the main limiting factors being the energy density of batteries and the structural weight of the aircraft.

5⃣ The operating range of fuel cell electric aircraft is limited by the weight of the fuel cell system, which is in turn set by the maximum power requirement - this can be overcome by designing aircraft weight-reducing technologies and lighter fuel cell systems.

6⃣ As more fuel is needed for aircraft to fly longer distances, the weight of the fuel and its storage tank is decisive in determining the range of the aircraft. Maximising the range of hydrogen aircraft is therefore dependent on reducing the weight of hydrogen tanks.

7⃣ Unlike kerosene, #hydrogen fuel cannot be stored in the aircraft's wings. Retrofitting current aircraft by placing hydrogen tanks in the cabin would lead to a reduction in available space for passengers. To avoid this problem, hydrogen aircraft must be designed from scratch.

8⃣ #Contrails are a major source of uncertainty when it comes to the climate impact of aviation. As hydrogen-based contrails would be different from #jetfuel-based ones, further research is needed to reduce uncertainty about their climate impact and to form mitigation strategies.

If you're interested in these recommendations, you can read the full report at aiazero.org/resources🔖