Clean & Sustainable

Requires only table salt and water, both of which are abundantly available. Once filled, it can last for years. Couple it with renewable energy and you will have a truly clean and sustainable battery.

Independently Scalable

The power rating (kW) and the energy capacity (kWh) can be independently scaled depending on the need.

Environmentally Safe

No toxic chemicals used. Even if the battery leaks, the chemicals are environmentally benign thus safe. At an event of short-circuit, the only result is increase in temprature of water by few degrees.

Affordable Solution

The storage materials (salt and water) are abundant and combined with long life of the system, the levelized cost of energy storage is on par with the current battery solutions.

Key Figures

Energy conversion efficiency
Energy density
0.5 kWh
per cubic meter of reservoir
Power density
0 kW
per cubic meter of membrane system



How does the battery work?

The blue battery system consists of two major elements: the water storage tanks and the membrane stacks. There are three storage tanks, one with fresh water, one with concentrated salt water and one with diluted salt water.

During the charging phase, the diluted salt water is split into concentrated salt water and fresh water in the membrane stack and stored separately. The separation occurs under due to the applied electric field, a process known as Electrodialysis (ED).

During the discharging phase, these two streams are combined on which energy is released. This energy is then converted to electricity with the help of the membrane stack with a process called as Reverse Electrodialysis (RED).

Pilot Demonstration

Currently a pilot scale demonstration is functional at TheGreenVillage, Delft, The Netherlands. This battery will supply energy to nearby sustainable student households.
Check out our pilot projects page for more information.

More info. & specs.