Larson’s research interests include engineering, economic, and policy-related assessments of advanced clean-energy systems, especially for electric power and transport fuels production from carbonaceous fuels (biomass, coal, and/or natural gas) and for efficient end use of energy. His work addresses technologies of relevance to developed and developing countries. Larson maintains long-term collaborations on energy and sustainability with colleagues in China (Tsinghua University and the North China Electric Power University) and in Australia (University of Queensland). He has also participated in collaborative research efforts with colleagues across the United States and in Brazil, Cuba, India, Italy, Jamaica, Sweden, and elsewhere. He is currently collaborating with ecologists at the University of Minnesota in an effort to better understand the potential of alternative biomass resource/conversion options to sustainably deliver negative carbon emission transportation in the US by mid-century. Larson was part of the Princeton team that contributed extensive analysis to the National Research Council report, America’s Energy Future: Technology and Transformation (2009). He was also the Co-Convening Lead Author of the Fossil Energy chapter of The Global Energy Assessment (2012) and a Lead Author (bioenergy) of the Renewable Energy chapter. Past research efforts have included ones focused on analysis of technology systems for modernizing renewable-biomass as an energy source, including advanced gasification-based technologies for power generation and for production of transportation fuels. These efforts have included assessments of potential gas-turbine based biomass electricity supply and use in sugarcane industries, in pulp and paper industries, and in stand-alone electric power generation. Recent work has focused on analysis of fossil fuel/biomass co-processing systems with CO2 capture and storage, for co-production of clean transportation fuels and electricity. Larson supervises student research and occasionally teaches courses in the engineering school at Princeton. Since 2008, he has also held an appointment as a Senior Scientist with Climate Central, a nonprofit, non-partisan science and media organization created to provide clear and objective science-based information to diverse audiences about climate change and its potential solutions.