The most frequently asked questions about the GREENROCK salt water batteries

How much space is needed for a GREENROCK storage?

This is one of the most frequently asked questions. Besides the interest in how a saltwater battery works, space requirements and costs are at the top of the ranking of the most frequently asked questions.

Space requirement GREENROCK Home System

Less than half a square meter for a 5 kWh GREENROCK Home System.

Yes, salt water batteries are larger and heavier than other storage technologies. In the following picture we show a comparison of the size of a human and a battery stack with 2.5 kWh capacity. You need 45 x 45 x 96 cm floor space per 2.5 kWh GREENROCK Home System. These measures already include the space needed for housing and a nice cover of the batteries.

size comparison

In the GREENROCK standard solutions the power electronics are placed on top of the batteries. The batteries on the other hand are not stackable. Please note, one battery stack has 140 kg. Therefore, a stable base is required.

The power cabinet for a single-phase system measures 45 x 45 x 90 cm and is placed on a block of two battery stacks. If you plan a three-phase system, you need two power cabinets. Below is an illustration of installation possibilities for the single- and three-phase systems. GREENROCK Home systems are available from 5 – 30 kWh.

set-up Home system

The following illustration shows the installation of a 10 kWh GREENROCK Home System, single-phase. The four battery stacks of 2.5 kWh each are placed on the ground. Power electronics are placed on top of these stacks. One cabinet for single-phase systems, two cabinets for three-phase systems.


Saving space

You can gain a few extra centimeters by doing without the housing parts for the saltwater batteries. In this case you can place the stacks closer together. The 2.5 kWh unit measures 32 x 33 cm of floor space.

References with little space requirement

An example of a space-saving installation is a single-family home in Germany. The GREENROCK storage unit is located under the cellar stairs. Learn more about it.

Space is in the smallest hut. This proverb describes the installation of a GREENROCK battery storage at a tiny house in the Netherlands. Here is a short video about it.

How much does a GREENROCK storage cost?

Depending on the size of the storage and the electronics used, GREENROCK storage systems are available from 800 EURO per kWh. GREENROCK contains all the electronics, such as inverters and intelligent energy management system for visualization and control. All systems are emergency power-capable as standard and can be extended for off-grid operation. If there is a blackout in your neighborhood you have light when it stays dark at other homes. Not all storage systems from other manufacturers offer this option.

Tip for price comparison:

Make sure that necessary accessories such as inverters and energy management systems are included in the calculation. Other manufacturers may offer batteries and necessary accessories separately. Your local GREENROCK partner will provide you with advice and calculations for your personal requirement.

How does a salt water battery work?

Learn more under The Saltwater Battery