Foreword

One of the major challenges of the twenty-first century is how to meet growing energy demand in a sustainable manner. Energy demand worldwide has increased with the growth in population and in per capita energy use. Over the past several decades, energy demand has increased most rapidly in developing countries. Even so, per capita energy use in developing countries remains far lower than in developed countries. Energy demand is projected to continue to grow in the coming decades, due to continued population increases and the continued need for economic development. Where will the supply come from to meet this growing energy demand? Fossil fuels currently supply approximately 80 percent of world energy demand, but overwhelming reliance on fossil fuels is not a sustainable energy strategy. The fossil fuel supply is finite. While peak oil may or may not be reached anytime soon, fossil fuels are an exhaustible resource and cannot be relied on indefinitely. Even if fossil fuels were not an exhaustible resource, continued reliance on fossil fuels causes major environmental problems. Combustion of fossil fuels has been the primary driver of increases in the greenhouse gas concentrations in the atmosphere that intensify global warming. Fossil fuels are also a principal contributor to local and regional air pollution and other environmental problems.