Energy is the total power derived from natural resouces -- the sun, oceans, fossil fuels, wind, etc, and can be converted into electrical energy for the consumption of our needs and benefits.
The sources of energy are --
electrical energy, heat/ thermal energy, chemical energy, mechanical energy, nuclear energy, energy in the form of electromagnetic radiation - light.
The two major resources  of energy are --
1. Reneweable  resources -- The resources that can easily renewed( replaced), does not cause any pollution, are inexhaustible and cannot be affected by human activities are --  Air, water and solar energy, and the resouces undergoing research and development are -- solar, biomass, wind, biogas, tidal, geothermal.
2. Non - reneweable resources -- The resources, that cannot be easily renewed, causes pollution, easily exhaustible and mainly affected by human activities  are --  Mineral, Oil, Natural Gas, petroleum, Coal, water power.