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Step 5: Connecting the batteries
The PowerRouter has an integrated intelligent 24 Vdc battery manager capable of temperature-compensated
charging based on current and voltage regulation, which extends the life of the batteries and improves the
charging process of the batteries. This way it also ensures the safety.
Suitable types of battery
Different types of battery can be connected to the PowerRouter.
Sealed lead-acid batteries
Sealed lead-acid batteries offer good value for the money. These batteries are available in a 2 V version as
well as versions that produce a higher voltage (e.g. 12 V), which are made up of multiple 2 V cells. There are
two versions of this battery type: gel-cell batteries (with a gel-like electrolyte) and AGM (Absorbent Glass Mat)
batteries. Both battery types have a sealed construction and are 100% maintenance-free.
Lead-acid wet battery
Lead-acid (wet) batteries are also suitable. However, they require more maintenance than the sealed type: for
instance, they need to be regularly replenished with distilled water. Charging also generates gas. This means
that these batteries must be installed in a well-ventilated room.
Determining the required battery capacity
The purpose of a self-use system is to enable the household to maximise its own use of the solar power it
generates. In other words, the batteries must be able to store enough energy to meet the power requirements
in the home during the evening and night. The average energy consumption during non-daylight hours can be
used to work out the required battery capacity.
The battery capacity can be compared using the calculation tool at www.PowerRouter.com. This tool enables
you to enter the annual consumption and the consumption profile. The energy that will be available with
different battery sizes is shown. The calculation is based on the rule of thumb that 1 kWh is stored for every 100
Ah (24 V) and that a fully-charged battery can be discharged to 50% DOD.
Nedap recommends that you connect a battery of at least 150 Ah at 24 V. The capacity value is specified in the
battery datasheet as a C10 value (the 10 here stands for the time to discharge).
For determining the (optimum) battery capacity it is important to keep three things in mind:
1.
Annual household consumption (kWh)
2.
Household consumption profile (at home or away during the day)
3.
Size of PowerRouter system (kW)
Optimum battery capacity recommendations
5.0 kW PowerRouter Solar Battery Battery bank with a capacity of at least 200 Ah but not more than 600 Ah
3.7 kW PowerRouter Solar Battery Battery bank with a capacity of at least 200 Ah but not more than 500 Ah
3.0 kW PowerRouter Solar Battery Battery bank with a capacity of at least 200 Ah but not more than 400 Ah
