Complementary hydrogen, electrofuels and biofuels
Clean fuels could be an alternative to gasoline, if only they could be produced for cheap.
A Few Details
Liquid hydrogen must be produced by electrolysis and compressed to a liquid state, which makes it costly.
Electrofuels are produced to store renewable energy in chemical bonds of liquids capable of replacing gasoline. They are only experimental.
Biofuels from crops or algae are another fuel path, although their production could compete with food production.
At least, these fuels could be used for planes, which can’t carry heavy batteries. As well, the biofuels currently mixed with gasoline, as in the US, could be reassigned to planes.