How I Automated EV Charging Using EVCC, an EG4 Solar Inverter and a Tesla Mobile Connector

[danielraffel]

I just posted this on my blog and figured I'd share it here too in case folks searching for these solutions find them useful.

TL;DR Looking to charge your Tesla using the Universal Mobile Connector with EVCC? Or, do you have a Lux Power or EG4 inverter and battery and want to use it with EVCC? If so, keep reading.

Since EVCC is open source, it didn’t matter that it lacked native support for my Lux Power/EG4 inverter and non-smart Tesla charger. A buddy and I purchased a third-party dongle designed to extract data from the otherwise closed inverter, and we figured out how to integrate it with EVCC. This allowed us to manage charging for our similar setups, which each include an EG4 18kPV inverter, a Tesla Model 3, and a Tesla Universal Mobile Connector (UMC). The dongle streams data via MQTT, enabling EVCC to track critical metrics such as solar generation, grid usage, and battery status, while also supporting dynamic control of battery discharge during fast charging.

In addition to integrating the inverter, I set up TeslaBLEHttpProxy to let EVCC smartly control the (dumb) Tesla UMC. This works by enabling EVCC to communicate with the Tesla vehicle through the proxy locally over Bluetooth, allowing near real-time charging adjustments based on solar and grid conditions. With this setup, I can dynamically adjust charging parameters such as amperage, enable fast charging, limit charging to solar excess, and more.

To better manage energy costs, I configured EVCC to account for PG&E’s seasonal tariffs under my Electric Home Rate Plan (E-ELEC). Using a custom formula, the tariffs automatically adjust between summer and winter rates, with different time-of-use (TOU) pricing tiers. This ensures that I can charge at the lowest possible cost by prioritizing solar energy, battery reserves, or grid power depending on availability and cost.

Overall, this custom setup offers an integrated solution that balances solar self-consumption, grid tariffs, and vehicle charging. It’s ideal for anyone comfortable with configuring these components and looking to maximize their EV charging efficiency.

If you’re interested in setting up something similar, check out this repository. You can clone it, copy evcc.env.sample to evcc.env, and edit the values to match your setup. If you don’t plan to use InfluxDB, be sure to uncomment DISABLE_INFLUX in evcc.env. Once your values are set, run gen.sh to generate evcc.yaml with your customized configuration. The repo includes pre-configured PG&E seasonal tariffs for California, which can be easily removed from your config if they don’t apply to your setup.

While your setup is likely to differ, this repository serves as a useful example of how to use EVCC to:
• Integrate a Lux Power/EG4 inverter using a third-party dongle.
• Enable smart control of a Tesla with a UMC charger via Bluetooth using TeslaBLEHttpProxy.
• Configure seasonal summer/winter tariffs, like those used by PG&E.

Requirements:
• EVCC – Open-source EV charging controller.
• Monitor My Solar Dongle – If you’re integrating an EG4 or Lux inverter.
• TeslaBLEHttpProxy – If you’re planning on using a Tesla UMC with EVCC.
Note: The device running the proxy must be within Bluetooth range of the vehicle.

[raymond79nl]

You are a life saver!

I spend a day or so trying to get a custom charger to work for my Tesla M3 with a first gen (dumb) TWC. Was stumbling over issue after issue until I found this. Works perfectly, thx!