What are the leading waste-to-energy (WtE) operator companies in Japan that design, build, and operate facilities converting municipal solid waste into electricity and heat? These companies are key players in Japan’s advanced waste management ecosystem, using incineration and energy recovery technologies to reduce landfill use and generate renewable power. The question focuses on identifying major operators based on installed capacity, technological innovation, and project execution scale. It also highlights their role in supporting Japan’s circular economy and energy efficiency goals.