Urja — IoT Smart Energy Monitor

Granular sub-metering of electrical appliances and departmental feeder lines is essential for identifying phantom energy drain and balancing commercial phase loads. Conventional commercial sub-meters are costly, lack open telemetry APIs, and offer no programmatic mechanism for automated load shedding.

Lead Author and Hardware Developer. Developed the ESP32 hardware and firmware interface, designed the load control switching stages, conducted comparative bench calibration against laboratory standards, and authored the research paper accepted for publication.

An ESP32 microcontroller interfaces with an industrial PZEM-004T dedicated energy metering module over optically isolated UART. The PZEM IC measures true RMS voltage, RMS current, active power, accumulated active energy, AC grid frequency, and instantaneous power factor. The ESP32 formats and transmits telemetry over Wi-Fi while driving solid-state relays for threshold-triggered or remote load shedding.

Implemented UART communication firmware with cyclic redundancy checks (CRC) to guarantee data integrity against electromagnetic noise generated by inductive loads. Built an embedded web dashboard and MQTT publisher for real-time visualization of electrical parameters. Structured automated protection logic to disconnect loads during severe overvoltage or sustained overcurrent conditions. Conducted rigorous measurement trials comparing Urja's readings with calibrated laboratory bench meters across varied load types.

Demonstrated measurement accuracy within ±1% across standard domestic and laboratory load conditions. Research paper formally accepted at BPUT Multi-International Conference 2025, scheduled for publication in CRC Press, Taylor & Francis proceedings.