We had a power outage last week that gave me a good change to test out my battery system. Like any successful test it uncovered a few bugs. The battery system is based around the Enphase Smartswitch combined with a bank of 4x 10.2KWh battery packs that use LiFePo4 batteries combined with 53 380W LG Solar panels all using IQ7 microinverters.

The concept is that the batteries and the solar microinverters can create a standalone power grid when main power is unavailable. The house can then run on battery power, with the solar providing additional power and charging.

On the positive side, when the power dropped out, I didn’t notice. On the negative side, I didn’t notice! Normally I would have seen an alert on my phone, but I added a small distribution switch for some experiments in the upper garage a while back and didn’t notice that I put it on the non-gen-bat circuit. When power dropped off that switch went down, and the Enphase system couldn’t send out a note to say we were off grid power.

It is an easy fix to change that to a POE powered switch so it is not only on the gen power circuits, but also the APC symmetra UPS. I have also added some detection circuitry that will do some home automation tasks in that case, including an announcement over the PA.

The biggest downside of not knowing the power was out was that I continued to use power with abandon! I had a few extra larger servers powered up, plus laundry, dishwasher, and a bunch of other things kicking. I was drawing about 10KW at the time, which is a pretty typical draw for me during the day. 40KWh won’t last long at 10KW.

Once I figured it out, I did some server-shutdowns to reduce usage for things I didn’t need. The batteries ended up lasting through to the next morning before I fired up the generator.

I am going to automate some system shutdown for things that are non-essential, especially my 40+ drive backup SAN, and the math array. I also have a cell modem connection for sending notifications in the case both the power and the internet are offline.

Fun stuff for sure!