UMBRELLAS IN JAPAN KEY THINGS YOU NEED TO KNOW
Does Tongwei photovoltaic panel need a battery
In cloud conditions, the panel output can be as low as 80%, meaning you will need a reliable battery system to hold energy stored for those days when the generation via solar isn't enough. [pdf]
Japan Sendai Microgrid Case
On March 11, 2011, the devastating Great East Japan Earthquake hit the Tohoku district, inflicting catastrophic damage on the district's energy supply system for a number of days. Despite the extreme devastation, the Sendai Microgrid resumed supplying power and heat to customers after a short interruption,. [pdf][FAQS about Japan Sendai Microgrid Case]
