Source and reservoir types of fossil energy

This article presents the long-run and recent perspectives on coal, oil, and gas – how much countries produce and consume, where our fossil fuel reserves are, and what role the fuels play in our energy and electricity systems. Primary energy sources take many forms, including nuclear energy, fossil energy -- like oil, coal and natural gas -- and renewable sources like wind, solar, geothermal and hydropower. These primary sources are converted to electricity, a secondary energy source, which flows through power lines and. For most of human history, our ancestors relied on very basic forms of energy: human muscle, animal muscle, and the burning of biomass such as wood or crops.