Real-Time Electricity Consumption Monitoring System Based on ESP32 and Google Sheets

Abstract

This research aims to design and implement a low-cost, easy-to-install, and auditable household-scale electricity consumption monitoring system. The system is developed based on an ESP32 microcontroller and a PZEM-004T sensor (up to 100 A), equipped with a 20x4 LCD local display and automatic recording to Google Sheets for daily, weekly, and monthly recaps. The methods used include hardware design, data acquisition programming and scheduled uploads, and accuracy validation against reference instruments (digital meter/DT-266 and kWh meter). The test results show high accuracy in single-point tests with relative errors of 0.089% (voltage), 0.11% (current), and 0.55% (power), all below 1%. Multi-time tests (09.00; 12.00; 03.00) recorded an average voltage error of ≈0.35% with ΔV ≈0.8 V, confirming the consistency of the readings. During a six-day energy validation, the Google Sheets total of 19,358 kWh matched the kWh meter reading of 19,310 kWh (a difference of 0.048 kWh; ≈0.25%), with an average consumption of ≈3.22 kWh/day. The device is capable of monitoring consumption and estimating pre-bill costs.