We use static power – in our homes and factories – and moving power – in our cars, trucks and planes.
How heavy the power source is matters more and more a we move from static, into moving. Most especially for planes which will probably never be fuelled by batteries.
So light, compact energy powerhouses such as existing, hydrocarbon-based petrol are needed.
That is why quite a lot of posts here have been about the holy grail of artificial photosynthesis – making hydro carbons from current atnmospheric CO2, rather than releasing the old carbon, in fossil fuels, that is causing so trouble.
There is another way though. As the Hindenberg and Space Shuttle disasters show, hydrogen packs a punch. The problem is making it economically.
These guys publish an exciting new development in Nature.