Tesla says the 7MWh project makes this one its biggest energy storage development in Asia, and like its giant Australian Powerpack system, it was completed with eye-watering speed -- the hardware was apparently installed in just two days.

1/ In the event of a grid outage, this Osaka Powerpack installation is designed to provide emergency backup power to safely move a train and its passengers to the nearest station - https://t.co/yS6VALjIbR https://t.co/2Ui6jUmGwo — Tesla (@Tesla) March 27, 2019

Osaka's trains are some of the busiest in Japan, transporting millions of people every day, so Tesla's Powerpack will undoubtedly prove a blessing during power interruptions. While the company's energy division tends to take a backseat to its EV work, its 2018 figures show it's playing an increasingly prominent role not only within the Tesla empire, but across the energy storage landscape in general. Last year the company deployed 1.04Gwh of energy storage, nearly triple the 358MWh rolled out in 2017.

Update (3/27 7 PM): This post has been updated to reflect that Osaka Powerpack is Tesla's largest energy storage system in Asia, not the largest one in all of Asia.