Petroleum, natural gas, coal, nitrogen, uranium and water power are examples of conventional sources of energy. They’re also called non-renewable sources of energy and are mainly fossil fuels, except water power. Rising growth of population has created a tremendous pressure on the conventional resources of energy and thus the concept of sustainable development get prominent … Read more Non- metallic and conventional minerals [coal,petroleum and natural gas), (c) hydro electricity and non conventional sources of energy (Solar, Wind, bio-gas),(d) energy sources Their distribution and conservation.