Aaron Douglas will briefly review recent data on the use of fossil fuels for generating electricity and the concomitant emission of greenhouse gases. He will also examine the emerging prospects for replacing all fossil fuel based energy--including the entire current U.S. and world's electrical, transportation, and heating-based energy consumption–with various forms of renewable-based energy. The major renewable alternatives to be ranged against the fossil fuels include wind, solar, and hydropower. Other renewable sources such as fusion, biofuels, wave, tidal, and geo-thermal could also play a role in the world's energy future. Another issue in this comparative assessment is cost. The U.S. owns the world's largest coal reserves and cheap, abundant coal holds down the cost of U.S. electricity production. However, technological development plays a major role in the notable recent decreases in the price of renewable source based energy. Finally, raw energy production is only part of the story. For example, the natural gas delivery system is a critical element of the nation's infrastructure. Douglas’ presentation will examine the economic and technological possibility of replacing this infrastructure for renewable sources.