Energy engineering combines knowledge from the fields of physics, math, and chemistry with economic and environmental engineering practices. Energy engineers apply their skills to increase efficiency and further develop renewable sources of energy.  The development and growth of a country depends cheap and abundant supply of electric power. Next to the food, the fuel and power are the most important items on which economy of country depends. Apart from its use in industrial organisations and domestic purposes, electricity is needed in agriculture for pumping water required for irrigation and in defence for improving production methods and other various operations.