The world's energy sources can be broadly divided into three categories; fossil, nuclear and renewable fuel sources. The proven fossil energy reserve at present is around 36X1021 Joules and it is the prime source of energy in today’s world. Sun, wind and water are perfect energy sources, depending on where we are. Those are non-polluting, renewable, efficient, simple and readily available. The acceleration of technological development has opened the door to continuous and rapid worldwide economic growth and has in fact allowed the world to achieve energy sustainability using many different energy sources. Annual GDP and Energy Consumption of least and developing countries and region are increasing exponentially. On the other hand, annual GDP and Energy Consumption of developed and rich countries and region are increasing linearly. The Earth, the Sun, the Galaxy and the Universe have more than enough energy resources to power our civilization for the following decades, centuries and millennia. The future sources of energy should be renewable for our environmental balance and better globe.