ESP32 Smart Electricity Meter with Web Dashboard

Smart electricity meter uses ESP32 with SCT-013-030 current transformer (30A) to non-invasively measure household power consumption without modifying wiring. CT clamp wraps around live wire. Circuit: CT output -> burden resistor (33 Ohm) -> bias voltage divider -> ESP32 ADC. ESP32 calculates RMS current using EmonLib, multiplied by assumed voltage (220V) to get apparent power. Calibration: run with known load (1000W heater = 4.5A at 220V), adjust calibration factor. Web dashboard: live watts display, hourly/daily/monthly kWh bar charts, cost calculation with configurable tariff, bill prediction, export 12 months CSV. Push alert when consumption exceeds daily budget. API endpoint for Home Assistant. Multiple CTs: monitor 3-phase supply with 3 CT sensors. Libraries: EmonLib, WiFi, ESPAsyncWebServer, ArduinoJson, NTPClient.

Detailed Project Description

ESP32 Smart Electricity Meter with Web Dashboard measures electrical parameters accurately and turns them into consumption figures, cost estimates and alerts.

How It Works
1. The metering module measures voltage, current and power on the line.
2. The controller reads the values over UART/I2C/ADC and computes energy (kWh) and cost.
3. Data is displayed and logged to a web dashboard with daily/monthly totals.
4. Alerts are sent for over-load, low battery or power failure.

Key Components and Their Role
- ESP32: dual-core Wi-Fi + Bluetooth microcontroller that runs the firmware, reads the sensors and hosts the network connection.
- OLED display (SSD1306): 128x64 I2C display used to show live readings and status.

Implementation Steps
1. Collect the components and study each module's datasheet (pin-out, voltage, interface).
2. Wire the circuit on a breadboard following the pin mapping; power sensors from the correct rail (3.3 V / 5 V).
3. Install Arduino IDE, EmonLib, ESPAsyncWebServer and the required libraries; flash a minimal test sketch for each module separately.
4. Write the main firmware: read sensors → process → drive outputs / send data.
5. Configure network or cloud credentials and test communication end-to-end.
6. Calibrate thresholds, add error handling (reconnect, sensor time-out) and run a long-duration test.
7. Finalise on a PCB / enclosure and document wiring, code and results.

Key Features
- Voltage / current / power / energy
- Cost calculation
- History charts
- Alerts

Expected Output
On completion the student will have a web meter showing live electrical values and consumption history.

Deliverables
- Complete source code with comments
- Circuit diagram and pin mapping
- Project report with screenshots and results
- Demonstration-ready build