- Global carbon dioxide emissions due to commercial aviation by 2025 will be 1.5 billion tons.
- The entire European Union of 457 million people emits 3.1 billion tons/year.
- A typical Boeing 737-800 requires more than 11MW of continuous power when cruising.
- Hydrogen delivers three times the energy of gasoline of the same weight (click on graphic to see hydrogen way to the right):
- The problem is that for the same amount of energy provided, liquid hydrogen takes up four times more space.
- A hydrogen-powered aircraft will only produce water vapor and some nitrogen compounds, no carbon dioxide.
The European Union, in a 2003 study led by Airbus and 34 other partner companies looked into CRYOPLANE, to be powered by liquid hydrogen. The indication was that there could be some oxides of nitrogen and water vapor emissions. However, the residency time of this vapor would only be 6 months, whereas carbon dioxide could hang around for 100 years. Plus, aviation emissions are increasing at twice the rate of that from ground transport. For now, Airbus is looking into replacing conventional auxiliary power units with hydrogen fuel cells.
article of five years on this subject remains conjectural.