Introduction

An Energy Efficient Home System is a smart home automation project designed to monitor and control home appliances to reduce energy consumption. By integrating IoT, sensors, and microcontrollers, this system ensures electricity is used efficiently, helping save energy and lower electricity bills.

It is highly useful for residential automation, smart cities, and sustainable living demonstrations.

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Objective of the Project

• To monitor energy consumption of home appliances
• To control devices automatically based on usage and occupancy
• To integrate IoT for remote monitoring and control
• To reduce electricity wastage and promote sustainable living

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Working Principle

1. Sensors like PIR motion sensors detect occupancy in rooms
2. Appliances such as lights, fans, and ACs are connected via relays to a microcontroller
3. Microcontroller monitors usage patterns and switches off idle devices automatically
4. Optional IoT integration allows monitoring and controlling devices via mobile app or web interface
5. Energy-saving algorithms help optimize electricity usage

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Components Required

• Arduino / ESP32
• Relay Module (for controlling appliances)
• PIR Motion Sensor (for detecting occupancy)
• Voltage / Current Sensor (optional, for real-time power monitoring)
• Wi-Fi Module (ESP8266 / ESP32 built-in for IoT)
• LCD / OLED Display (optional, to show status)
• Jumper wires, power supply, and load devices (like bulbs, fans)

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Block Diagram

Sensors (PIR, Voltage/Current)
         ↓
   Microcontroller (Arduino/ESP32)
         ↓
     Relay Module
         ↓
 Home Appliances (Lights, Fan, AC)
         ↓
  Optional: IoT Cloud / Mobile App

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Circuit Connections (Arduino Example)

PIR Sensor

VCC → 5V
GND → GND
OUT → D2 (Arduino Digital Pin)

Relay Module

IN1 → D8 (Arduino Digital Pin for Light)
IN2 → D9 (Arduino Digital Pin for Fan)
VCC → 5V
GND → GND
COM → Appliance Live Wire
NO  → Appliance Live Input

Appliances

Connect via relay COM and NO pins
Neutral goes directly to appliance

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Arduino Code (Energy Efficient Home System)

#define PIR_PIN 2
#define LIGHT_RELAY 8
#define FAN_RELAY 9

void setup() {
  pinMode(PIR_PIN, INPUT);
  pinMode(LIGHT_RELAY, OUTPUT);
  pinMode(FAN_RELAY, OUTPUT);

  digitalWrite(LIGHT_RELAY, LOW); // Initially OFF
  digitalWrite(FAN_RELAY, LOW);
  Serial.begin(9600);
}

void loop() {
  int motionDetected = digitalRead(PIR_PIN);
  
  if(motionDetected == HIGH) { // Room occupied
    digitalWrite(LIGHT_RELAY, HIGH);
    digitalWrite(FAN_RELAY, HIGH);
    Serial.println("Room Occupied: Lights & Fan ON");
  } else { // Room empty
    digitalWrite(LIGHT_RELAY, LOW);
    digitalWrite(FAN_RELAY, LOW);
    Serial.println("Room Empty: Lights & Fan OFF");
  }
  
  delay(1000);
}

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Code Explanation

• PIR sensor detects human presence in the room
• Microcontroller switches relays ON/OFF based on occupancy
• Lights and fan are turned off automatically when no one is present
• Optional IoT integration allows remote control and real-time monitoring

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Advantages

• Saves electricity by switching off unused devices
• Reduces electricity bills
• Improves home automation and convenience
• Easy to integrate with IoT for remote control

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Applications

• Smart homes and apartments
• Smart offices and workplaces
• Schools, hospitals, and hotels
• IoT-based sustainable energy projects

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Future Enhancements

• Add current/voltage sensors to measure exact energy consumption
• Mobile app control for manual override and monitoring
• Integration with voice assistants like Alexa or Google Assistant
• Automated scheduling of appliances based on time or energy rates

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Conclusion

The Energy Efficient Home System is a practical mini + innovation project that demonstrates automation, energy savings, and IoT integration. It makes homes smarter, reduces energy wastage, and contributes to sustainable living.