Question

When are we going to use $H_2$ as fuel for vehicles?

Answer 1

Hydrogen gas has a high calorific value and is pollution free as it produces $H_{2}O$. This makes hydrogen sound very good for use as a fuel. But there are problems associated with hydrogen. Being a gas it is very difficult to contain and transport. Also, there is a high possibility of fire due to leakage. In order to make hydrogen usable, these problems must be overcome.