World’s Largest Vanadium Flow Battery Goes Online In USA

BETHESDA, MD – The largest flow battery system in the world, capable of storing and delivering grid-
scale power instantaneously, has received permission to operate from the local utility and will begin full
operation in the weeks ahead, announced Prudent Energy, the manufacturer of the VRB® Energy
Storage System. The project’s commissioning marks a significant point in the deployment of large-scale
electricity storage systems and will be used to expand onsite power generation at an agricultural
processing facility in California owned by Gills Onions, a leader in sustainability, innovation, and
technology.

“This project unleashes the power of energy storage for industrial companies and the grid of the future.
It proves that multi-megawatt-hour VRB® systems can be delivered today. We expect dramatic benefits
for a company like Gills Onions, to help them manage their operating costs,” said Prudent Energy Senior
Vice President Jeff Pierson.

“Prudent Energy storage is clean, quiet and safe, making it an attractive, sustainable solution for onsite
power generators like us. We are impressed with the innovative technology behind Prudent’s Vanadium
flow battery, and are excited to be the first company in the United States to deploy a VRB® system on
this scale,” said Steve Gill, Owner/Partner of Gills’ Onions.

“Lower Utility Bills on a Sustainable Basis”

One of the VRB® system’s obvious benefits is that it allows Gills Onions to reduce utility bills by storing
electricity when rates are lowest and delivering that electricity during expensive peak rate periods.
Electricity prices increase during high use periods, especially for six hours in the afternoon when the
local utility, Southern California Edison, must call on peaking generators to meet demand. That
additional cost of electricity production is passed to the customer via Time of Use (TOU) rates.

Although Gills Onions generates a significant portion of its own electricity, it still depends every day on
the local utility. Enter Prudent. By charging the VRB-ESS® typically at night, then discharging that power
during the afternoon peak period, Gills reasoned it can substantially lower its power bill each year.

In 2011, Gills Onions was recognized by McDonald’s Corporation on the merits of their sustainability
achievements. Proving how important such a commitment is to effective business relations, Gills Onions
received McDonald’s annual Innovation Award for its waste-to energy project, including Prudent’s flow
battery, a zero waste initiative, and participation in The Climate Registry.