In recent years, cities around the world have adopted ambitious renewable energy portfolio targets. In 2010, then-Mayor Gavin Newsom announced a goal for San Francisco to be 100 percent powered by renewable energy by 2020. A task force he convened wrestled with this challenge for more than a year. Mayor Ed Lee recently released the task force’s report with recommendations and a detailed view of the challenges and opportunities of powering the city with clean energy. What are cities new and old doing to become 100 percent renewably powered?

+ Danielle Murray, San Francisco Department of the Environment
+ Stefan Schurig, World Future Council
+ Bob Dixson, Mayor, Greensburg, Kansas