Smart Energy Meter Using IoT with MQTT Dashboard & Alerts

Real-Time IoT Smart Energy Meter With SMS Alerts

Ever wanted instant insight into your home’s electricity use from anywhere? This Smart Energy Meter Using IoT delivers exactly that — plus safety alerts straight to your phone. 📱⚡

This project combines an ESP32 microcontroller with a PZEM-004T energy sensor to continuously measure electrical parameters like voltage, current, power, energy, frequency, and power factor — and broadcasts them in real-time using the lightweight MQTT protocol. When the system detects abnormal conditions such as high voltage or unusual power draw, it sends an SMS alert to a pre-registered mobile number using a cloud SMS API — all without costly cloud subscriptions.

🌟 Why This Project Matters

Traditional energy meters only show cumulative usage — you can’t monitor, control, or react to energy patterns in real time. This IoT energy meter fills that gap with:

Live data visualization on an MQTT dashboard
Real-time SMS notifications for safety alerts
Low-cost, easy-to-build hardware using ESP32 and PZEM-004T
Open and customizable platform for makers and learners

🔧 How It Works

Measure Energy Parameters:
The PZEM-004T module continuously reads voltage, current, power, energy, frequency, and power factor. Factory calibration makes it more reliable than typical standalone sensors.
Send Data Over MQTT:
The ESP32 publishes measurement data via MQTT to a dashboard in real time. MQTT’s publish/subscribe model means you get fast updates with minimal bandwidth.
Display Locally and Online:
Values are shown on a local LCD and on a web-based MQTT dashboard that you can open in any browser.
Trigger SMS Alerts:
If an abnormal condition, such as high voltage, occurs, the code triggers a secure HTTP call to the Circuit Digest Cloud SMS API to send an alert instantly.

📡 Why MQTT?

Unlike HTTP, MQTT is designed for IoT:

Lower latency: Faster, nearly real-time data transfer.
Reduced bandwidth usage: Efficient for constant updates.
Scalable: Many devices and dashboards can subscribe to one topic.

For readers who want to expand this build further, the ESP32 project collection on CircuitDigest offers dozens of real-world implementations.

🛠 Example Use Cases

✔ Monitor daily power consumption remotely
✔ Get SMS alerts if voltage goes beyond a safe limit
✔ Integrate data with smart home systems (Home Assistant, Node-RED)
✔ Base for advanced energy analytics or automation

Whether for home automation, energy efficiency experiments, or student IoT projects, this system provides a practical, connected solution.