Building a Temperature and Humidity Controlled Greenhouse with LCD Display

Introduction

Greenhouses provide an ideal environment for growing plants by maintaining optimal temperature and humidity levels. However, manually monitoring and controlling these conditions can be a daunting task. In this article, we will guide you through the process of creating a Temperature and Humidity Controlled Greenhouse with an LCD display using Arduino. This project will not only make your life as a gardener easier but also ensure your plants thrive in the best possible conditions.

Working Principle

The primary goal of this project is to automate the greenhouse environment, making it self-sufficient and capable of maintaining the desired temperature and humidity levels. We achieve this by integrating various sensors, an Arduino microcontroller, and actuators to control heating, cooling, and humidity systems.

Things You'll Need

1. Arduino Uno or compatible microcontroller
2. DHT22 or DHT11 sensor for temperature and humidity
3. LCD display (16x2 or similar)
4. Relay module for controlling heaters and fans
5. Heating element (e.g., heater pad)
6. Cooling fan or system
7. Water misting system
8. Breadboard and jumper wires
9. Power supply for Arduino and peripherals
10. Greenhouse with adequate ventilation

Circuit Diagram

[Insert circuit diagram here]

Working of the System with Arduino

1. Temperature and Humidity Sensing: The DHT22/DHT11 sensor is placed inside the greenhouse to monitor the ambient temperature and humidity levels continuously. These readings are then fed into the Arduino.
2. LCD Display: The Arduino processes the sensor data and displays the current temperature and humidity values on the LCD screen, allowing you to monitor the greenhouse conditions in real-time.
3. Control Logic: Based on the desired temperature and humidity levels you've set, the Arduino compares the current readings from the sensor and decides whether to activate the heating, cooling, or misting systems.
4. Heating and Cooling: The Arduino controls the heating element and cooling fan through relay modules. When the temperature falls below the set value, it activates the heating element, and when it rises above the threshold, it turns on the cooling fan.
5. Humidity Control: To regulate humidity, the Arduino can activate a water misting system when the humidity falls below the desired level.

Arduino Code

Here's a simplified example of Arduino code for this project:

#include <LiquidCrystal.h>
#include <DHT.h>
 
#define DHTPIN 2
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);
 
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
 
void setup() {
  dht.begin();
  lcd.begin(16, 2);
}
 
void loop() {
  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature();
  
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Temp: ");
  lcd.print(temperature);
  lcd.print("C");
  lcd.setCursor(0, 1);
  lcd.print("Humidity: ");
  lcd.print(humidity);
  lcd.print("%");
  
  // Add your control logic here to adjust temperature and humidity
  // using relays and actuators based on desired levels.
}

Conclusion

Building a Temperature and Humidity Controlled Greenhouse with an LCD display using Arduino is a rewarding project for any gardener or electronics enthusiast. Not only does it ensure your plants receive the ideal conditions for growth, but it also demonstrates the power of automation in agriculture. With this project, you can optimize your greenhouse's environment, save time, and ultimately grow healthier and more abundant crops. Happy gardening!