In the afternoon of May 12, Prof. Klaus Töpfer, the Executive Director of the Institute for Advanced Sustainability Studies (IASS), former Under-Secretary-General of the United Nations (UN) and former Executive Director of the United Nations Environment Programme (UNEP), delivered a keynote speech on German Energy Policy and Denuclearization to the students in Tongji University. Wu Zhiqiang, the Vice President of Tongji University gave remarks.

During the speech, Prof. Töpfer illustrated the energy challenge facing the current world with a multitude of accurate data, pointing out that we can meet this challenge with following four aspects. They are, namely, to promote clean production and use of traditional fossil fuels, to increase the efficiency of energy use, to develop new energy including biomass energy and solar power, and to adjust the current energy structure. Students on the scene raised many questions related to their own majors to Prof. Töpfer, who answered all of them patiently.    

Prof. Töpfer is a leading expert in environment and energy as well as a pioneer in international environment and sustainability. He is the Founding Director and current Executive Director of the Institute for Advanced Sustainability Studies (IASS). He was former Under-Secretary-General of UN, former Executive Director of the UNEP, former Federal Minister for the Environment, Nature Conservation and Nuclear Safety and former Federal Minister for Regional Planning, Housing and Urban Development. He has received numerous awards and honors, including the Federal Cross of Merit and the German Sustainability Award for his lifetime achievement.