There are essentially three fossil fuels: coal, petroleum (or oil), and natural gas. It is worth looking at each one of them separately because, although they are often lumped together they are, in fact, quite different. ADVERTISEMENT. Coal is the result of millions of years of vegetation being accumulated and altered. In order words, present Coal supplies around 30% of the primary energy needs all over the world, generating 40% of electricity. Some of the biggest producers are China, USA, India and Indonesia. Compared with oil and natural gas, it is one of the most abundant sources of energy. Fossil fuels (coal, oil, propane, and natural gas) account for more than 80% of total energy consumption in the United States. Alternative forms of energy have, to this point, proven to be