The arrangement complements Mitsui's $10m investment that was part of the $36.5m in Series C preferred stock \A\financing raised by Sunverge earlier this month   

"Japan is the second largest market for solar PV growth, which in turn is driving demand for intelligent distributed energy storage solutions," says Ken Munson, Sunverge co-founder and CEO.

The country added a record 9.6GW of nameplate capacity in 2014, according to the International Energy Agency.