Dr. Charles F. (Chuck) Kutscher is a Fellow and Senior Research Associate of the Renewable and Sustainable Energy Institute, a joint institute between the University of Colorado-Boulder and the National Renewable Energy Laboratory (NREL). He served as the Director of the Buildings and Thermal Sciences Center at NREL from 2013 until his retirement in July 2018. He has worked in the field of renewable energy for over four decades, during which time he has led research in a wide range of energy efficiency and renewable energy technologies. He is a Fellow of the American Solar Energy Society (ASES) and served as the Society’s chair in 2000 and 2001. He led the ASES study, Tackling Climate Change in the U.S., a 200-page report detailing how energy efficiency and six renewable energy technologies can greatly reduce U.S. carbon emissions by 2030. He is the lead author of the third edition of the college textbook, Principles of Sustainable Energy Systems, and has served as an adjunct professor at the University of Colorado at Boulder and the Colorado School of Mines.