The Center for Climate and Energy Solutions (C2ES) was named the world’s top environmental think tank in a global survey of top public policy research institutes.

The University of Pennsylvania’s 2011 Global Go-To Think Tank Rankings are based on a survey of more than 1,500 policymakers, scholars, journalists, think-tank executives and others worldwide. The survey assessed more than 5,300 organizations nominated in 30 categories to create a global list of top think tanks by region and policy area.

C2ES’s predecessor organization, the Pew Center on Global Climate Change, was named the world’s top environmental think tank in the same survey in 2009.  The center began operating as C2ES in November 2011, and is listed in the new survey under its former name.

“While our name has changed, we remain as committed as ever to fact-based analysis and common-sense solutions to our climate and energy challenges,” said C2ES President Eileen Claussen. “We are thrilled to again be recognized as the world’s top environmental think tank.  I’d like to commend the C2ES staff and thank all of our partners and supporters in the United States and abroad for helping to make this possible.”

The independent, nonpartisan center provides impartial information and analysis on energy and climate challenges; convenes policymakers and stakeholders to work toward consensus solutions; works with members of its Business Environmental Leadership Council and others to promote on-the-ground action; and promotes pragmatic, effective climate and energy policies at the state, national and international levels.

The annual survey, first published in 2007, is directed by James G. McGann, assistant director of the University of Pennsylvania’s International Relations Program and director of the Think Tanks and Civil Society Program.

The World Resources Institute and Chatham House ranked second and third, respectively, among the study’s top 30 environmental groups. Brookings Institution was named the top overall think tank. Additional categories in which the report ranks organizations include health policy, international development, and security and international affairs, among others.

The complete study, released in January 2012, is available online here.