Due to the COVID-19, many countries including Japan have reinforced regulations at the borders. As many international students could not enter Japan due to the COVID-19 pandemic, some universities offered online education services as an alternate. On the other hand, since April 2020, many of international student livening in Japan have not been able to go back to their countries.

In 2020, global phenomena such as unprecedented scale forest fires, storms, melting glaciers, and dramatic declines in northern polar glaciers are very likely to be caused by climate change. By the middle of this century, it is becoming clear that it is not enough for Germany’s greenhouse gas emissions to be cut by 80％ compared to 1990 levels. In December 2015, to meet the climate targets agreed in the Paris agreement, stricter cuts from Germany are required, limiting global temperature rises to an average of 2 ℃（better 1.5 ℃） compared to pre-industrial levels. With regard to the transition of Germany’s energy systems, this paper begins with a comprehensive model of the Germany power and thermal sector in future energy systems with a major contribution to renewable energy technologies. Based on REMod-D （Renewable Energy Model - Germany）, the basic structure is summarized briefly. Then, we introduce some of the simulation results by REMod-D models by Philip et al. （2020）. The aim is to assess the energy transition and the possibility of climate-neutral systems in Germany.