Home Battery Arbitrage System Kit with ESP32 + Relay
Build a Home Battery Arbitrage System with ESP32 + Relay to Slash Peak Electricity Bills
Every part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.
This kit enables you to build a complete ESP32‑based battery arbitrage controller that charges a battery bank when your electricity tariff is low and automatically discharges it to power home loads during peak hours — all while staying aware of net metering to avoid exporting battery energy back to the grid. If you pay time‑of‑day electricity rates, the system directly cuts your bill by shifting consumption to cheaper periods without manual intervention.
What You'll Build
You’ll assemble and program a smart power gateway that senses real‑time voltage, current, and tariff schedules, then toggles high‑power relays to route grid or battery energy. The finished unit sits inside a DIN‑rail enclosure, logs consumption data to an SD card, and displays live metrics on an OLED — a fully functional energy‑arbitrage device you can scale in future to larger batteries.
What You'll Learn
- Precision AC energy monitoring using PZEM‑004T and three DC INA219 sensors for battery, load, and grid side
- Multiplexing I2C sensors with TCA9548A to expand your ESP32’s capability without address conflicts
- Time‑synchronised relay switching logic using DS3231 RTC and dynamic tariff schedule processing
- Designing a net‑metering‑aware control loop that prevents battery energy export while feeding local loads
Kit Contents
| Component | Quantity |
|---|---|
| ESP32 Dev Board | 1 |
| PZEM-004T | 1 |
| INA219 | 3 |
| TCA9548A I2C Mux | 1 |
| 4-ch Relay Module | 1 |
| DS3231 RTC | 1 |
| MicroSD Module | 1 |
| LM2596 Buck Converter | 1 |
| 0.96in OLED | 1 |
| 100nF Caps | 15 |
| PCB Prototype Board | 3 |
| DIN Rail Enclosure | 1 |
| 12V 5A PSU | 1 |
| Soldering Iron | 1 |
| Solder Wire | 1 |
Why Buy This Kit Instead of Sourcing Parts Separately
| Factor | Sourcing Separately | Compoden Kit |
|---|---|---|
| Compatibility checks | You verify every part | Pre-tested as a system |
| Build support | Forums and scattered tutorials | AI companion trained on this exact project |
| Time to first working build | Days of debugging | Hours, with step-by-step guidance |
| Shipping coordination | Multiple sellers, multiple delays | One shipment from Bengaluru in 3-5 days |
Who This Kit Is For
Final‑year B.Tech ECE/EEE students building a capstone project around energy management, Smart India Hackathon teams working on grid‑interactive IoT solutions, and embedded energy enthusiasts prototyping for startups will find this kit exactly matches their requirement. It’s also popular among MTech researchers at IITs and NITs who need a reliable hardware baseline for tariff‑optimisation experiments.
Built and Backed by Compoden
Every Compoden kit ships with an AI build companion trained on this exact project — accessible via a QR code on the box, with WhatsApp and email backup. We’ve spent 10 years building projects for makers, schools, and institutions across India. If a part fails because of a manufacturing defect, replace it free within 7 days.
What if I get stuck during the build?
Scan the QR code to launch the AI companion that walks you through each step — from soldering the prototype board to flashing the ESP32. You also get direct WhatsApp access for hardware-specific queries.
Can this kit work with my existing inverter battery?
Yes, the system measures battery voltage and current up to 5A with INA219. For larger battery banks, the same control logic applies as long as you match the relay rating and use appropriate shunts.
How does it handle net metering so I don’t export battery energy?
The PZEM-004T continuously monitors import/export direction. The firmware prevents discharging when grid export is detected, and only powers local loads that remain behind the meter.
What if my electricity tariff schedule changes frequently?
The DS3231 RTC maintains accurate time, and you can update tariff windows via the SD card — simply drop a new config file onto the MicroSD. No need to reprogram the ESP32.
Charges battery during cheap tariff. Discharges to power home loads during peak tariff. Net metering aware.
What's in this kit
Choose your assembly option:
- Soldering Kit — 25W soldering iron, 60/40 solder wire, flux, and small perfboard for permanent assembly.
- Breadboard Combo — 800-point full-size breadboard with 65-piece jumper wire pack for solderless prototyping.
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Shipping Information
- Prepaid Orders: ₹75 for orders up to ₹999, FREE shipping above ₹999
- COD Orders: ₹125 shipping + ₹50 COD fee = ₹175 total
- Delivery Timeline: Dispatch in 1-2 days, delivery in 2-7 days depending on location
Returns & Warranty
- 7-Day Return: Manufacturing defects only (approval required)
- Warranty: 7 days from delivery
- Non-Returnable: Batteries, consumables, cut wires, clearance items