Philadelphia is the latest American city to commit to transitioning to a future powered by 100% clean energy, the Sierra Club reports.

Across the United States the number of cities to have made this pledge now stands at 139. Philadelphia, the country’s sixth biggest city, will move to using green electricity in municipal operations by 2030, city-wide by 2035 and for all energy by no later than 2050.

“Young people around the world are demanding bolder strategies and action to address the ever growing crisis of climate change. We have a responsibility to make the transition to renewable energy. As we ask business and industry to evolve, the City should lead the way, and I am proud to work with the Mayor and my colleagues to take action at this critical moment,” said Philadelphia Council Member Maria Quinones-Sanchez.