There will never be a single replacement for fossil fuels such as coal and gasoline. There are, however, several technologies that, in combination, can meet the need. These include photovoltaic solar, concentrated solar, wind, geothermal, biomass, and tidal. The alternative with the greatest potential for reducing greenhouse gas emissions however is improved energy efficiency through such means as tighter appliance standards, improved manufacturing processes, better transmission, and green building construction. Unfortunately, in the U.S. at least, Federal energy subsidies are heavily tilted toward politically connected fossil fuel industries rather than emerging renewable ones or energy efficiency.

Mike