I’ve always been fascinated by the intersection of renewable energy and smart home technology, so when I decided to invest in an electric vehicle (EV), I knew I wanted to make the charging process as sustainable and automated as possible. After some research and experimentation, I’ve managed to create a seamless solar-powered EV charging system that not only saves me money but also reduces my carbon footprint. Here’s how I did it!
My Setup
I’ve equipped my home with a 22 kWh solar panel system, two 10 kWh BYD home batteries, and a Wallbox Pulsar Plus charger. My EV of choice is a Polestar 2, which has a range that perfectly suits my daily commute needs. To manage the entire system, I use Home Assistant along with Node-RED for custom automation flows.
The Automation Logic
The core of my system is an automated charging schedule that takes into account both my solar energy production and real-time electricity prices. Here’s a breakdown of how it works:
- Daytime Solar Charging: During daylight hours, any excess solar energy that isn’t used by my household is directed to charge my EV. This ensures that I’m using free, renewable energy whenever possible.
- Nighttime Grid Charging: If the battery is depleted by evening, the system switches to nighttime charging when electricity rates are at their lowest. This is managed through an integration with the Nordpool energy market API, which provides hourly price updates.
- Dynamic Adjustments: The system continuously monitors both solar production and grid prices, adjusting the charging schedule in real-time to maximize savings and efficiency.
The Dashboard
To keep everything under control, I’ve created a custom dashboard in Home Assistant that displays key metrics:
- Current battery state of charge
- EV charging status
- Solar production
- Electricity prices
- Charging schedule
This visual overview allows me to tweak settings on the fly and ensures that the system is always operating at peak efficiency.
The Results
Since implementing this setup, I’ve noticed a significant reduction in my electricity bills. Best of all, I’ve been able to charge my EV almost entirely on solar power during the summer months, which is incredibly satisfying!
Tips for Others
If you’re considering a similar setup, here are a few tips:
- Start Small: Begin with a basic solar panel system and gradually add batteries and EV charging capabilities as your needs grow.
- Leverage Smart Home Automation: Tools like Home Assistant and Node-RED are incredibly powerful for creating custom solutions.
- Monitor and Adjust: Keep an eye on your energy usage and adjust your automation rules as needed to optimize performance.
I’d love to hear from anyone else who’s experimenting with solar-powered EV charging or has tips for improving the system further! 
