Liquid Hydrogen as a Fuel

Liquid Hydrogen as a Fuel:- Liquid hydrogen is an important rocket fuel. A primary condition for a rocket fuel is that its mass be as small as possible for giving amount of energy produced. Since hydrogen has low mass and high enthalpy of combustion, therefore, it was considered as an ideal rocket fuel. It was used in Saturn-V rocket that enabled the first astronauts to land on the moon and it has been the main fuel in the space shuttle rockets. Both the hydrogen and the oxygen needed to burn the hydrogen are carried on the rocket in liquid form.

The important advantages of hydrogen as a fuel for rockets are:-

1.   It releases greater energy per unit weight of the fuel.

2.   The only product of combustion is water.

3.   There is no emission of environmental pollutants such as CO, CO2, SO2, oxides of nitrogen, hydrocarbons, aldehydes and lead compounds etc.

4.   Internal combustion engines can easily be modified for use of hydrogen as fuel.

5.   Fuel cells for generation of electric power with conversion efficiency of 70 -85% have been successfully operated commercially.