Alternative energy is an energy source that is an alternative to fossil fuel. The motive behind looking for alternative energy is to have control over CO2 emission. An increase in CO2 emission has already brought unfavorable changes to the environment of this planet and the number keeps rising approaching its alarming level.

This is threatening the sustainability of life on planet earth in the long run. There is a strong need to promote existing alternative energy sources, for example, marine energy, the hydroelectric, wind, geothermal, and solar power and to look for new discoveries and innovations in this field.