Nathan Lewis, Ph.D. (right), the George L. Argyros Professor of Chemistry at the California Institute of Technology, spoke to a large crowd Sept. 23 for the International Center for Advanced Renewable Energy and Sustainability (I-CARES). His lecture, “Where in the World Will Our Energy Come From?” examined a range of alternative energy issues and was very popular among students and faculty. Afterward, director of I-CARES Himadri B. Pakrasi, Ph.D. (left), the George William and Irene Koechig Professor of Biology in Arts & Sciences and professor of energy in the School of Engineering & Applied Science, and Chancellor Mark S. Wrighton survey the crowd with Lewis.