Why a battery solution is a profitable investment for housing associations

A typical housing association spends money on electricity to supply each of their apartments, along with common areas, washer and dryer, AC, car parks, common houses, and possibly administrative offices.

These expenses can be lowered with the installation of solar panels; however, this introduces a new problem for housing associations, namely that the consumption of solar energy does not align with the time frame of solar energy production.

This problem can be solved by installing a battery, that stores surplus solar energy for later use.

The housing association will be able to monitor the generated solar panel energy, which shows when it makes the most sense financially e.g. to do the washing.

Furthermore, when monitoring housing associations will be able to see if they should invest in a larger battery and/or more solar panels.

Why should housing associations invest in energy storage?

Our energy and electricity needs are changing constantly, which makes us increasingly dependent on energy storage in our daily lives. What we need is a power supply, that provides secure and reliable electricity 24/7, and here batteries are ever more sought after than ever to meet this demand.

Moreover, we need to make better use of renewable energy sources and reduce our dependence on non-renewable fossil fuels, such as oil and gas. Solar and wind power, however, are not always available when needed, as clouds block the sun and the wind blows irregularly.

Nevertheless, when using batteries for storage of solar and wind power, we are provided with reliable electricity 24/7, without negatively impacting the environment.

Now more often than ever, housing associations are investing in solar panels. However, changes in tariffs have resulted in solar panels being less profitable for owners, as the generated electricity is fed into the grid for a very little, if any, return.

This problem can be solved by installing an energy storage solution. Such a solution will better utilise the power generated from the solar panels, which will lead to larger savings on electrical bills.

Why should housing associations invest in a redox flow battery?


It is possible to scale the battery to fit specific energy needs, due to a separation of the power (kW) and the capacity (kWh) in the battery, which makes it easy to meet the needs of the specific housing association.


The battery is safe and cannot catch on fire or explode, as the energy is stored in a liquid electrolyte that mainly consists of water.


The battery is environmentally-friendly and 99% recyclable because it has separated major operating components (tanks, electrolyte, pumps, electrode stack etc.), that are either recyclable or reusable in different ways.


The cost of the battery over its lifetime is low, which makes it a profitable investment.

Housing associations can profit from a battery by storing the surplus, generated energy for later use, when the sun isn’t shining and/or at night. The graph below shows the accumulated cost of the lifetime of a redox flow battery, in comparison to other types of battery solutions.

a comparison of li-ion, lead-acid- and flowbatteries

You make money from day one

A VisBlue battery makes it possible for you to utilise more of the power generated from the solar panels.

This investment can be funded in two ways:

1. your own savings,
2. or through a loan.

The graph below illustrates in percentage how much of its solar panel production a housing association utilises, which is exemplified on the right side of the graph, where the progress is shown using a blue line. The left side shows how much electricity a battery can store in kWh/year, where this is illustrated using a red line.

The housing association in the graph below has a power consumption of approx. 260,000 kWh/year and a solar production of approx. 184,000 kWh/year (these figures are not illustrated in the graph). Without a battery, the housing association uses in average only 42% of the energy that its solar panels produce. If a 40 kW battery is installed, this enables the housing association to boost the utilisation rate of its solar panels to around 77%.Boligforeningen i nedenstående graf har et forbrug på ca. 260.000kWh/år og en solenergiproduktion på ca. 184.000 kWh/år (disse tal er ikke illustreret i grafen). Uden et batteri bruger boligforeningen i gennemsnit kun42% af den energi, som dens solceller genererer. Hvis et batteri på 40 kW installeres, løftes udnyttelsen af solcellerne, og boligforeningen bruger nu i gennemsnit 77% af den genererede energi fra dens solceller.


NB! This scenario exemplifies an estimate of both private and common consumption and use. It is possible for a housing association to differentiate between private and common electricity consumption and use, and, therefore, allocate the electricity from both the solar panels and batteries solely to the common expenses, such as common laundry, etc.

Why should housing associations choose a redox flow battery solution from VisBlue?

Customisable and upgradable

The VisBlue Battery Solution is scalable and built using our own standard modules, which makes the solution easily customisable.

This customisation is also visible as it is possible to install a battery from VisBlue both indoors and outdoors, as well as in container solutions.

Furthermore, the battery is easy to upgrade, if the housing association’s electricity pattern or energy needs change, as it is built for disassembly.


The founders of VisBlue are still a part of the university society, which keeps VisBlue updated regarding research in the area and allows VisBlue to participate in the project all over the world.

Optimised control strategy

VisBlue has developed an optimised control strategy to ensure an optimal efficiency.

Every installation is simulated to fit the specific housing association, to make sure the optimal size is provided.