18.08 kWh home battery with backup power, 3-phase

Two battery modules of 9.04 kWh, a Sigen Energy Controller of 8 kW, the 3-phase Power Sensor and the Sigen Energy Gateway HomePro TP of 30 kW.

With two modules you get the full power of the controller: 8 kW charging and discharging. That's also what's available during an outage, spread across three phases. Enough to keep a household running normally, including a dishwasher or a washing machine if you switch it on while the rest is quiet.

Why the gateway belongs with it

A SigenStor without a gateway is a battery that lowers your energy bill. Nothing more. During an outage nothing switches over, because the controller isn't allowed to form its own grid without a gateway. The HomePro TP does that: it isolates your installation from the public grid and lets the controller build its own 400 volt network on the circuits you've assigned.

What to sort out beforehand

Backup power across three phases means the installer looks per phase at what's connected. A heat pump or an EV charger on one phase can throw things off balance during island operation. In practice we therefore often leave those circuits out of the backup power. That's not a shortcoming of the system, it's simply choosing what 8 kW has to carry.

When this is too much

If you use under 3,500 kWh a year and don't have equipment that can't go without power, this is generously sized. The standard 18.08 kWh package without a gateway saves just as much on your bill and costs 1,300 euros less.

Installation

Budget 500 euros extra for the backup power work in the meter cupboard.