Professor Seung-Gyu (Andrew) Sim visited the GETPPP Green School on February 24, 2017. The professor from University of Tokyo came to discuss his paper titled "Inelastic Supply of Fossil Energy and Competing Environmental Regulatory Policies." Professor noted that that under the assumption of elasticity of fossil energy pricing, the "Piguovian taxation" and "cap-and-trade" policies amount to the same. The author demonstrates that under inelastic fossil energy pricing, "cap-and-trade" policies outperform 'Piguovian taxation" maximizing global welfare.