A 1 GWh energy storage
solution is now in the
realm of possibility.

VRB® Energy’s GW-Class VRB-ESS® serve an entire new segment of the energy storage market. Custom engineered to replace peaker plants and firm solar and wind to help meet 100% renewable energy targets.

Suitable for pairing with solar and wind generation as power plants of the future, 250MW 1GWh systems are custom engineered in large-footprint configurations utilizing super-sized tanks and large-format cell stacks.

From California to China, from Saudi Arabia to South Australia, the rapid transition to low-cost renewable energy will be enabled by pairing it with long-duration (4 to 8 hours) storage to deliver firm power on demand, and when it is needed most.

Unlike other battery formats, VRB-ESS are utility-scale equipment well-suited to this task: manufacturing of large-format cell stacks (which determine system power rating) is easily scalable, and electrolyte (which determines the energy rating) can use large tank farms; both of these elements together result in a much more effective solution than trying to string millions of tiny cells of differing voltages together.

VRB-ESS® GW-Class systems are robust systems specially engineered to deliver 100 MW or 250 MW of power for 4 to 10 hours to meet the needs of large-scale solar and wind farms, and to replace utility peak power plants.

Utilities and grid operators from Australia to Arizona are struggling with integration of large amounts of solar power replacing fossil fuel in wholesale grid supply projects. Solar power is also being adopted at a rapid pace by commercial, industrial and residential users alike. This creates a “duck curve” problem, where utilities have to turn down other forms of generation during the peak solar hours – only to ramp up the power as solar output wanes and evening peak power usage spikes.

This can be addressed with our 4-8 hours of energy storage products, to balance electricity grids and shift valuable solar energy from day to night.

VRB-ESS® GW-Class benefits:
• Pair VRB-ESS® with solar and wind generation to create a power plant solution that delivers firm and reliable power throughout the day
• Lower lifecycle cost of energy LCOE than traditional forms of generation
• Shorter lead time to implement than a new peaker plant
• More than 100% of hours provide a variety of ancillary services (as opposed to peaker plants that are only operated about 5% of hours)


100% depth of discharge with no degradation yields low LCOE.


The electrolyte can be fully recycled at end of project lifetime, saving cost and avoiding the expensive disposal costs of other batteries.

System Safety

Systems are non-flammable and operate at low temperature and low pressure.


Proven performance and robust design yield high availability and low maintenance costs.

Fast Response

Fast dynamic response for transition between charge and discharge or between operating power levels in less than 100ms.


VRB-ESS® have been reviewed and are in compliance with European system quality and safety guidelines.

Each VRB Energy VRB-ESS® 1MW Power Module is composed of 20 stacks, pumps and controls. Tanks and electrolyte are separate based on desired system energy rating. A power conversion system (PCS) is included for a complete AC system.


Flow batteries store energy in liquid electrolyte, which doesn't degrade.

VRB-ESS® can be discharged each and every day to full depth of discharge without any capacity degradation, delivering greater operational flexibility and lifetime than lithium-ion batteries.

While lithium-based batteries are well suited to consumer electronics and electric vehicles, thier lifetimes can be limited.

VRB Energy’s VRB-ESS® technology can be discharged over an almost unlimited number of charge and discharge cycles without wearing out.
This is an important factor when matching the daily demands of utility-scale solar and wind power generation.


VRB Energy currently has over 750MWh of projects under development, with increasing interest being shown for storage projects of 8-hours duration.


VRB Energy has the most proven vanadium battery technology with extensive track record of reliable performance.


Storage duration can be increased from 4 to 6 or 8 hours at a low incremental cost providing project owners with ultimate flexibility.

VRB Energy has successfully installed and operated over 50 systems in more than 16 countries around the world.
Each VRB-ESS® can be combined with almost any volume of electrolyte according to the requirements of a particular application.

RED = VRB-ESS® kW-Class

Contact us to schedule a meeting to learn about VRB-ESS® GW-Class products.