RD20 is a conference of leading research institutes from G20 member nations, focusing on clean energy technologies and international collaboration. In order to prevent the spread of COVID-19, the 3rd RD20 was held online, and participants were able to take part in 2 separate sessions. The Technical Sessions (September 29 – October 1) severally focused on 3 specific themes: “sectoral approaches to decarbonization”, “social acceptance of hydrogen”, and “next generation energy management systems”. The subsequent Leaders Session (October 8) aimed to reach a high level consensus on a global collaboration toward a low-carbon society.