It's a Hydropower World

Brad Plumer reports news of a study published in Aquatic Studies finding that, in addition to facilities that already produce 16 percent of the world's electricity, "an additional 3,700 large hydroelectric dams are either under construction or being planned worldwide, largely in Latin America and Asia."

"All told, global hydropower production is on pace to double in the next two decades to 1,700 gigawatts, predict the study's authors, from the University ofTübingen in Germany. That would reduce the number of large free-flowing rivers on the planet by another 20 percent."

Plumer then goes on to examine the complex politics and economics of hydropower, including the desperate need for electricity in many developing countries and the surprising impacts of dams once they're built. On that latter point, the "Aquatic Sciences paper, by providing a comprehensive database of the 3,700 largest dams under construction, is hoping to help planners address some of these concerns. 'Clearly,' the authors note, "there is an urgent need to evaluate and to mitigate the social, economic, and ecological ramifications of the current boom in global dam construction."