On Thursday, July 17, former Vice President Al Gore issued a challenge to the American people:

Today I challenge our nation to commit to producing 100 percent of our electricity from renewable energy and truly clean carbon-free sources within 10 years.

This goal is achievable, affordable and transformative. It represents a challenge to all Americans - in every walk of life: to our political leaders, entrepreneurs, innovators, engineers, and to every citizen.

You can watch or read the speech on wecansolvit.org. Or you can read or listen to the audio of the speech on NPR.