Hydrogen versus gas in cars
For a long time people have talked about the idea of using hydrogen to fuel our transportation systems. There are some obvious advantages to this. When you burn hydrogen you don't release any CO2, the hydrogen combines with oxygen to form simple water. Batteries like you'd find in an electric car also store and release energy without emitting CO2 but those don't hold as much energy as the equivalent weight of hydrogen. Hydrogen theoretically stores 40,000 Wh/kg whereas even a good battery like the one used in a Tesla only stores 100 Wh/kg. The theoretical values aren't the whole story since converting hydrogen to motive force is less efficient than converting charge in a battery. And also you need tanks to store the hydrogen which I'll come back to later. But those don't overcome the magnitude of the difference and long range hydrogen cars are feasible in a way that long range electric cars aren't. On the other hand hydrogen has some big problems