I'm trying to find a way to optimize my Deye hybrid inverter setup for charging my electric vehicle (EV) using maximum solar power. My system includes a Deye hybrid inverter (SUN-15K-SG05LP3-EU-SM2), a 20 kWh LFP battery, and a Wallbox Pulsar Plus EVSE with OCPP, all integrated with SolarAssistant using MQTT and Home Assistant.
The challenge is that I live in a region where feeding energy back into the grid isn't allowed, so my inverter automatically throttles the solar power production to match my house's energy demand plus battery charging. I'd like to adjust my EV charging based on the maximum solar production available, but the inverter only reports the current PV output, which can lead to a feedback loop where starting my EV charger raises home energy usage and disrupts the production value used to control the charger.
I'm wondering if anyone has found a reliable method to calculate the maximum possible solar production in such a setup. Is there an MQTT topic that I'm missing in SolarAssistant? Or do I need to consider alternatives, like using a radiation sensor or forecasts?
1 Answer
It's actually simpler than it sounds! On the Deye, you can adjust the "zero export power" setting to 50W instead of the default 20W. Set your battery's target state of charge (SoC) to 80% in the ToU menu. This way, when you charge the EV, it won't drain the battery below 80%.
Next, put your EVSE in solar mode which will try to minimize grid usage to zero watts. Since zero is less than 50W, the Deye should maximize the PV output. While it technically works with the standard 20W setting too, increasing the threshold might create a more stable system. The key is how finely the EVSE can adjust current, so testing different settings could help!
Do I need the EM330 power meter to make this work with the Wallbox? I was hoping to avoid extra wiring and the $330 cost, but this does help clarify the process!