ABSTRACT

Global energy consumption in the last half century has rapidly increased and is expected to continue to grow over the next 50 years, however, with signiŽcant differences. The past increase was stimulated by relatively “cheap” fossil fuels and increased rates of industrializationin North America, Europe, and Japan; yet while energy consumption in these countries continues to increase, additional factors make the picture for the next 50 years more complex. These additional factors include China’s and India’s rapid increase in energy use as they represent about athird of the world’s population; the expected depletionof oil resources in the near future; and, the effect of human activities on global climate change. On the positive side, the renewable energy (RE) technologies of wind, biofuels, solar thermal, and photovoltaics (PV) are Žnally showing maturity and the ultimate promise of cost competitiveness.