Energy is the lifeblood of our society. It is essential to our quality of life and underpins all other elements of our economy. As we approach the dawn of the 21st century, renewable energy technologies offer a tantalizing promise: clean, abundant energy gathered from continuously self-renewing resources such as the sun, wind, earth, and plants.Research conducted over the past 20 years has been bringing this promise closer to fruition, and progress towards realization of the full potential of renewable energy is accelerating."For years, the renewables business has wanted to reach the point where, as sales volumes grew, prices dropped, making renewables more attractive and stimulating demand. This holy grail at last seems to be in sight."The Economist, April 18,1998, p. 57 This paper will briefly review the technical status, cost, and applications of major renewable energy technologies in 1998, and also discuss some of the socioeconomic impacts of wide-scale adoption of renewables.
PROGRESS IN RENEW ABLE ENERGY TECHNOLOGIESThe term "renewable energy" encompasses a broad spectrum of technologies, all of which are based on self-renewing energy sources such as sunlight, wind, flowing water, the earth's internal heat, and biomass such as energy crops, agricultural and industrial waste, and municipal waste. These resources can be used to produce electricity for all economic sectors, fuels for transportation, and heat for buildings and industrial processes.Renewable energy today contributes as much today to U.S. energy consumption as nuclear power (7%) and contributes slightly more (8%) to worldwide energy consumption.' Each renewable energy technology is in a different stage of development and commercialization. Some technologies are already commercial, at least for some situations and applications. 2 Of the renewable energy consumed in the United States in 1997, hydropower comprised 55%; biomass, including municipal solid waste, 38%; geothermal, 5%; solar, 1 %; and wind, 0.5%.3 Detailed information on over 7,000 facilities that generate U.S. grid-connected electricity from renewable resources is available electronically.4Renewable energy technologies offer important benefits compared to those of conventional energy sources such as fossil fuels or nuclear power.5' 6 Renewable energy resources are abundant; worldwide, one thousand times more energy reaches the surface of the earth from the sun than is released today by all fossil fuels consumed. Table 1 gives the energy delivered per square meter of land for four renewable resources. 7 Similar to fossil fuels, renewable energy resources are not uniformly distributed throughout the world. However, every region has some renewable energy resource. And, because different renewable energy resources complement each other, taken together they can contribute appreciably to energy security and regional development in every nation of the world, without dependence on foreign energy sources that are
