When thinking about energy alternatives to fossil fuels, we need to keep in mind how the United States uses its current fuel supplies. Based on a report by the Lawrence Livermore National Laboratory,
28% is used for transportation (gasoline and jet fuel)
40% is used to generate electric power
20% is used for direct heating (natural gas, coal)
32% is used by industry.
(Someone of you will immediately notice that this list adds up to more than 100% — that is because of overlap. For instance, some of the electric power is used by industry.)
The reported numbers vary, but the bottom line is that we use fuel for transportation, electricity, heat and industry in comparable amounts. We need to keep this in mind when discussing energy policies. If we miraculously replace all gasoline with biofuels (alcohol made from plants), we will affect only 28% of the total. So we need to address several “sectors” or uses if we want to significantly reduce fossil fuel emissions.
Scientists Talk Funny 