The United States led the world into the oil age in the 20th century. In the 21st century, we can lead the way out. With the security risks of petroleum dependence growing, and the environmental costs of fossil fuels becoming more apparent, the country faces compelling reasons to put renewable energy technologies to use on a large scale.

If there was ever a time when a major shift in the U.S. energy economy was possible, it is now. Three decades of pioneering research and development by both the government and the private sector have yielded a host of promising new technologies that turn abundant domestic energy sources-including solar, wind, geothermal, hydro, biomass, and ocean energy-into transportation fuels, electricity, and heat.