"Hydrogen Economy" is a scenario where hydrogen is used for fuel and transportation and also long distance carrier of energy. This is done to move away from fossil fuels based energy and significantly limit global warming. The idea of “hydrogen economy” has been on and off the energy agenda since the 1970s, with occasional spikes of interest but without ever catching hold—the drivers have simply not been strong enough.
Hydrogen has several advantages: it is a very clean fuel at the point of use, it can be used quite efficiently in fuel cells to generate electricity, and it can be used in most of the same applications as natural gas. But it is more expensive and more difficult to handle than natural gas, and it is not as versatile as electricity.