Retrofit photovoltaic storage

Retrofit PV storage and maximise your self-consumption

Be even less dependent on an external energy supply by retrofitting battery storage


We purchased our system 9 years ago without storage. We've now had a battery storage unit retrofitted and are delighted with how much more efficiently we can use the system.

Hajo Förster
Fürstenwalde

Retrofit photovoltaic storage: more efficiency for existing systems

Sooner or later, almost every PV operator will consider retrofitting their system with a  PV unit. Using more solar power yourself means higher returns because, by avoiding using an external energy supply, you save more than you would usually get when feeding into the grid.

PV-Speicher tagsüber laden, PV-Strom rund um die Uhr nutzen

Why retrofit a PV storage unit?

As feed-in compensation has faded more and more into the background as a source of income for photovoltaics, the focus is increasingly shifting onto boosting your self-consumption of the PV electricity in order to make a profit. The electricity generated yourself from your roof needs to be used even more efficiently.

For this reason, many operators reach their limits without retrofitting a photovoltaic storage unit. During the day, when most electricity is produced, most people are working. Time switches or Smart Home systems can only use a part of the generated electricity immediately. In the evening, when the PV system is no longer producing energy because it's dark, additional electricity is purchased from the energy supplier for hard-earned money. This problem can be avoided if the operator has their system retrofitted with a PV storage unit. In this way, electricity can be stored during the day and consumed as required.

Can any photovoltaic system be retrofitted with a storage unit?

In principle, almost every photovoltaic system can be retrofitted with a storage unit, but not every PV storage unit is suitable for this purpose.
PV-Wechselrichter mit effizientem PV-Speicher nachrüsten
PV-Anlage nachrüsten oder erweitern

If, at the beginning, retrofitting a PV system was not part of the plan at all, you're probably using a regular solar inverter. It's not compatible with battery storage units because it has a lack of connection options. There are two options available in this instance:

  • The existing solar inverter is replaced with a hybrid inverter
  • Alongside the solar inverter, the user adds a battery inverter with suitable storage

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