Oil, Gas, and Coal in Our Lifetime: Most of our energy comes from three fossil fuels: oil, natural gas, and coal. Why are fossil fuels an important source of energy? Where do fossil fuels come from? How much oil, natural gas, and coal does Michigan produce and consume? How long will the World’s supply of oil last? Find the answers to these questions and examine the concerns associated with our heavy use of fossil fuels by exploring this web module. Supports Energy Resources Unit Lesson 4.