Storage System Using 16 Old Nissan LEAF Batteries

Storage System Using 16 Old Nissan LEAF Batteries

The construction of a solar farm on the man-made island of Yumeshima in western Japan's Osaka was announced 3 months ago, but now it seems to be harvesting sunlight with full power.

"Hikari-no-Mori, or "Forest of Light," is a mega-solar project of 36,000 solar panels built on top of a landfill and managed by Sumitomo Corporation."

Surplus energy is stored in 16 lithium-ion battery packs taken from Nissan LEAFs.  The storage systems were developed by 4R Energy (Reuse, Resell, Refabricate and Recycle), a joint venture between Sumitomo and Nissan.

Reused electric vehicle batteries have power of 600 kW and energy of 400 kWh (400/16 is 25 kWh, so maybe those modules in the energy storage system are brand new?). Anyways, used ones from Nissan EVs will have ~70% (that threshold is typical after 100,000 km or 62,000 miles).

"The batteries have up to 70% of capacity remaining – the average left after 100,000 kilometers or five years of driving."

Mugihiko Ozeki, Senior Associate, Battery Business Development at Sumitomo, stated:

"This is the Osaka 'Hikari-no-mori Project' mega-solar power generation facility, a project with eight other companies. We are testing the system controlling the output of the battery packs that charge the energy generated by this 10-megawatt mega-solar power station, linking the data from the photovoltaic panels in real time."

Eiji Makino, President of 4R Energy, remarked:

"Depending on use, a battery's degree and rate of deterioration, and the battery's condition, vary by vehicle. So 4R has created a technology that allows us to have optimal control in regulating those conditions."

According to the press release, Sumitomo General Manager Norihiko Nonaka said that such energy storage systems are expected to be commercially viable in five years or so (we heard something similar from Solar City too).

Norihiko Nonaka, Sumitomo General Manager, commented:

"The electricity-value-chain is divided into three sections: electricity generation, transmission and distribution. We would like to focus on electricity generation and transmission. If we rely on renewables to obtain energy, like solar and wind, they don't always generate the necessary amount of energy and that may cause an issue with supply-and-demand. On the other hand, if the cost of batteries is too high and is economically inefficient, 4R will have to continue to work and investigate the situation and market in the long term, about five years or maybe after 2020. By saving energy into power storage or batteries, our goal is to create a balance in supply versus demand, or create a system with the battery to maintain the quality of the electricity."