Experimental study of a 400 V class DC microgrid for commercial buildings

This paper reports the experimental study of a 400 V class DC microgrid for an office building that has been constructed in Obihiro City, Hokkaido, Japan. The objective of this study is to develop a self-sustained distributed energy system by combining distribution energies, batteries, and appliances with DC power. This new DC energy system not only reduces the environment load and improves energy efficiency but also forms a community energy system that can become independent from utility grids and resistant to natural disasters. We have found that compared with AC power supply, the DC system, which uses power generated by solar panels as is, decreases CO2 emission more than 10%.