36.16 kWh home battery with backup power, single-phase

Four battery modules of 9.04 kWh under a Sigen Energy Controller of 6 kW, with the Power Sensor and the Sigen Energy Gateway HomePro SP. A total of 36.16 kWh.

People rarely buy this package to bridge a one-hour outage. They buy it because they have a lot of generation, a dynamic contract, and preferably want to run a whole winter week on their own supply. The gateway makes that usable too, at the moment the grid isn't there.

Four modules on one phase

Here it's worth taking a closer look. Thirty-six kilowatt-hours on a single-phase connection means a C-rate of 0.17. The battery can deliver far more than the controller lets through, and that 6 kW is the hard limit, even during backup power. If you see that 36 kWh mainly as storage, that fits fine. If you're hoping for more power during an outage, an extra module won't deliver that.

When 3-phase makes more sense

If you have a three-phase connection or one is planned, go for the 3-phase version instead. That delivers 8 kW and serves all three phases during an outage. On one phase, the other two circuits in your meter cupboard simply stay dead during a grid outage, even with 36 kWh sitting next to them.

What the gateway does

The HomePro SP disconnects your installation from the grid within zero milliseconds and puts the assigned circuits onto the battery. That figure applies in combination with the controller and the battery, exactly as this package is put together.

Installation

Backup power costs 500 euros extra in installation work. Four modules also need floor space: allow for a strip about a metre wide against a solid wall.