I recently embarked on a project to harness solar power to heat water for free, and I wanted to share my experience and the setup with the community. This project combines renewable energy with smart home technology, and the results have been nothing short of amazing.
The Background
A month ago, I had solar panels installed on my roof. While the installer set up the panels and inverter, I was curious about utilizing excess solar energy to heat water. Unfortunately, the installer wasn’t keen on integrating an immersion heater into the system. However, after some research, I decided to take matters into my own hands.
The Setup
Here’s what I ended up installing:
- Solar Panels and Inverter: The core of the system, integrated with Home Assistant using the cdpuk’s GivEnergy integration, which has worked flawlessly.
- Immersion Heater: A low-power 1kW immersion element wired to a TP-Link Kasa smart socket. This socket is rated for 13A, and with the low-power heater, it stays cool even during operation.
- Temperature Sensor: A OneWire sensor attached to the outside of the hot water tank to monitor the water temperature.
- Home Assistant Automations: Two simple rules to control the system:
- If the system is sending more than 1200 watts to the grid for over 5 minutes and the tank temperature is below 60°C, turn on the socket.
- If the system is sending less than 100 watts to the grid for over 3 minutes or the temperature exceeds 65°C, turn off the socket. Additionally, it turns off at sunset as a backup.
The Results
Since implementing this setup, my LPG boiler hasn’t been used at all, even during cloudy days. The system efficiently uses excess solar energy to heat water, and the integration with Home Assistant allows me to monitor and control everything from my phone or tablet.
Why This Matters
This project not only reduces my energy costs but also lowers my carbon footprint. It’s a testament to how smart home technology can work hand-in-hand with renewable energy to create sustainable solutions.
Final Thoughts
I encourage anyone with solar panels to consider similar setups. The key takeaway is that with a bit of research and the right integrations, you can maximize the efficiency of your solar energy system. If you have questions or need help setting something up, feel free to reach out!
Happy tinkering! 