IoT Temperature Monitoring with Node.js: Real-Life Implementation

In today’s rapidly advancing technological world, IoT temperature monitoring has become a crucial component in smart home systems. Using IoT devices to monitor and control temperature not only enhances comfort but also improves energy efficiency. In this article, we will delve into a practical example of implementing an IoT temperature monitoring and control system using Node.js.

Imagine a scenario where you can monitor and control the temperature of different rooms in your home remotely. This setup involves temperature sensors, a central Node.js server, and MQTT for real-time data transmission. The system will monitor the temperature and control heating or cooling devices based on the data received, ensuring an optimal environment in your home. This example demonstrates how IoT temperature monitoring can make a significant difference in smart home management.

Components Needed

• IoT Devices: Temperature sensors (e.g., DHT11 or DHT22).
• Node.js Server: A server to receive and process the data.
• Mosquitto MQTT Broker: For efficient data transmission.
• Smart Devices: Heating or cooling devices (e.g., smart plugs connected to heaters or air conditioners).

Setting Up the Temperature Sensors

First, we need to set up the temperature sensors in various rooms. These sensors will periodically measure the temperature and send the data to the Node.js server via MQTT.

Code for Temperature Sensor (Arduino)

#include 
#include 
#include 

#define DHTPIN D4
#define DHTTYPE DHT11
DHT dht(DHTPIN, DHTTYPE);

const char* ssid = "your_SSID";
const char* password = "your_PASSWORD";
const char* mqtt_server = "192.168.1.100"; // Your local Mosquitto MQTT broker IP

WiFiClient espClient;
PubSubClient client(espClient);

void setup() {
  Serial.begin(115200);
  dht.begin();
  setup_wifi();
  client.setServer(mqtt_server, 1883);
}

void setup_wifi() {
  delay(10);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
}

void loop() {
  if (!client.connected()) {
    reconnect();
  }
  client.loop();

  float temp = dht.readTemperature();
  if (!isnan(temp)) {
    char tempStr[8];
    dtostrf(temp, 1, 2, tempStr);
    client.publish("home/room1/temperature", tempStr);
  }
  delay(2000);
}

void reconnect() {
  while (!client.connected()) {
    if (client.connect("ESP8266Client")) {
      client.subscribe("home/room1/temperature");
    } else {
      delay(5000);
    }
  }
}

Extending the Node.js Server

Now, let’s extend the Node.js server from the previous blog to receive temperature data, process it, and control the heating/cooling devices as needed.

Code for Node.js Server

const mqtt = require('mqtt');
const client = mqtt.connect('mqtt://localhost:1883'); // Local Mosquitto MQTT broker
const smartPlugAPI = require('smart-plug-api');

const targetTemperature = 22; // Desired room temperature

client.on('connect', () => {
  console.log('Connected to MQTT broker');
  client.subscribe('home/room1/temperature');
});

client.on('message', (topic, message) => {
  const temperature = parseFloat(message.toString());
  console.log(`Temperature received: ${temperature}°C`);

  if (temperature < targetTemperature - 2) {
    smartPlugAPI.turnOn('heater');
    console.log('Heater turned on');
  } else if (temperature > targetTemperature + 2) {
    smartPlugAPI.turnOn('airConditioner');
    console.log('Air conditioner turned on');
  } else {
    smartPlugAPI.turnOff('heater');
    smartPlugAPI.turnOff('airConditioner');
    console.log('All devices turned off');
  }
});

Benefits and Applications

• Energy Efficiency: Automatically controlling heating and cooling based on real-time data helps in saving energy.
• Comfort: Maintaining an optimal temperature enhances the comfort of inhabitants.
• Scalability: The system can be easily scaled to include more rooms or different types of sensors.

This real-life example demonstrates the power of IoT devices combined with Node.js and MQTT for creating smart solutions. By implementing such an IoT temperature monitoring system, you can automate your home environment, making it more efficient and comfortable. This extended setup builds upon the foundations laid in our previous blog on real-time data synchronization with Mosquitto MQTT in Node.js, showcasing a practical application of the technology.

Stay tuned for more insights and examples on IoT and real-time data synchronization in our upcoming articles. If you have any questions or need further assistance, feel free to leave a comment or contact us directly.