What happens when you buy a solar roof, and you find out that the logging component has a Raspberry Pi MAC address? Perhaps nothing at the beginning, but sooner or later you'll have to scratch that itch and teach yourself some reverse engineering. Back in 2018 my family installed a solar roof at home. It came with a nice component to log and visualize your production and consumption statistics, and I was pretty surprised to see that its MAC address started with B8:27:EB, the OUI of the Raspberry Pi Foundation. During the 2021 Christmas holidays I finally decided to look into the device, a fun experience covering Modbus, radare2, and even PCB reverse engineering; in this presentation I will explain what I learnt and how I replaced the vendor software with a custom Python program and Home Assistant.