I built an autonomous ESP32-S3 controller to mine Bitcoin strictly using solar surplus (Zero grid consumption). Open Source! ☀️⛏️

Hey everyone, I just dropped v4.0 of my open-source Solar Crypto Mining Farm project, and I wanted to share the architecture.

The goal was simple: mine Bitcoin only when there’s free solar energy, and never pay for grid electricity to do it.

I’m running a 7,740Wp solar array into a custom mining fleet (Avalon Q, Nerd Octaxe, NerdQAxe+, and a BitAxe Gamma). To orchestrate this, I built an edge-computing controller using an auto-detected ESP32-S3.

How it works:

• The ESP32-S3 polls a 6-channel Refoss EM06P energy monitor every 30 seconds via HTTP API.
• It calculates the exact solar surplus across a bi-phase circuit (W, VA, and VAR).
• The decision engine automatically switches between 16 calculated mining profiles (from a single 21W BitAxe up to a 2001W full fleet blasting 104.5 TH/s) to perfectly match the live surplus.
• Relays handle the smaller ASICs, while the Avalon Q is controlled via CGMiner API commands to scale its modes (Low/Mid/High).

Everything is logged to a Supabase cloud database, and the ESP32 serves a live local web dashboard. I also built a live Three.js 3D visualization of the whole cluster operating in real-time.

You can check out the live 3D dashboard here:https://0xraphael.com/solar-mining-clusterAnd the full repo (including the v4 per-phase W/VA/VAR scalar math and Tasmota configs) is available here: https://github.com/0xrphl/Solar-crypto-mining-farm-maximization-control

Would love to hear any feedback on the energy modeling or the edge logic!