Choosing a Battery Storage System

Hello,

I’m planning to purchase a new PV system soon. I’ve received initial offers and started diving into the topic, but I think I need help choosing a good battery storage system.

My entire house is equipped with KNX, and I have various other devices, such as Shellys, totaling around 100 IoT devices. The basic idea is simple: when there’s excess electricity, the heat pump (which can also cool in summer) should ramp up.

But which storage system and inverter can be reliably integrated?

Offer 1 includes an SMA Sunny Tripower X inverter with a SonnenBatterie 10. I found a ha_sonnenbatterie module, but it’s hard to assess how reliable it is. It’s also concerning that I can’t find any documentation for the API used.

Offer 2 includes an all-in-one FENECON Home 15kW. It apparently has openEMS integrated, but this seems to be behind a paywall, and I really don’t want to pay a subscription for API access.

Both products are advertised here as “Made in Germany,” but my experience suggests extra caution is needed. Often, the digitalization is stuck at a level from 20 years ago. I’m seriously wondering if an international product might be the better choice.

TL;DR: Which battery storage systems are recommended and integrate well with HomeAssistant? Are there any experiences in the HA community?

The SMA Sunny Tripower X with SonnenBatterie 10 can integrate with Home Assistant via the ha_sonnenbatterie module, but the API documentation is lacking, and reliability can vary. The FENECON Home system with openEMS looks good, but the paywall for API access is a downside, though some users have found workarounds.