The world energy demand has been increasing in a rapid manner with the increase of population and rising standard of living. The world population has nearly doubled in the last 40 years from 3.7 billion people to the present 7 billion people. It is anticipated that world population will grow towards 8 billion around 2030. Furthermore, the conventional fossil fuel supplies become unsustainable as the energy demand in emerging big economies such as China and India would rise tremendously where the China will increase its energy demand by 75% and India by 100% in the next 25 years. With...