What you build
A working energy meter using an ESP32 with current and voltage sensors. It measures power consumption, uploads readings over Wi-Fi and shows live usage, daily totals and an estimated bill on a dashboard.
Modules
- Sensor circuit for current and voltage
- ESP32 firmware to calculate power and energy
- Wi-Fi upload of readings
- Dashboard with live power, daily kWh and estimated bill
- Alert when usage crosses a limit
What you will understand
- Measuring AC current and voltage safely
- Power, energy and power factor
- How an IoT device sends data to a server
How it is tested
- Calibration against a standard meter with known loads
- Error percentage at different loads
- Behaviour when Wi-Fi drops
What goes in the report
- Circuit diagram and component list
- Calibration results and error analysis
- Dashboard screenshots and cost estimate
Viva questions to prepare
- How do you calculate energy from power?
- What safety steps did you take with mains voltage?
- Where does the measurement error come from?