Solar-Powered Air Conditioning System - Electronic Engineering Guide
Table of Contents
1. Introduction
2. Objectives
3. Components Required
4. System Overview
5. Solar Power System Design
6. Air Conditioning Control Logic
7. Battery Storage and Power Management
8. Circuit Diagram and Integration
9. Software and Microcontroller Code
10. Applications
11. Challenges and Future Enhancements
12. Conclusion
1. Introduction
The Solar-Powered Air Conditioning System is an energy-efficient solution that combines photovoltaic technology with modern air conditioning systems. It reduces reliance on grid electricity by harnessing solar energy for operation, helping to cut electricity costs and carbon footprint.
2. Objectives
• Utilize solar energy to power air conditioning units.
• Design an intelligent control circuit for temperature regulation.
• Improve energy efficiency and reduce environmental impact.
• Enable monitoring and control using embedded systems.
3. Components Required
• Solar Panels (200W-1000W based on AC size)
• Charge Controller (MPPT preferred)
• Deep-cycle Batteries (12V or 24V)
• Inverter (12V/24V to 220V AC)
• Microcontroller (Arduino/ESP32)
• Temperature Sensor (DHT22/LM35)
• Relay Module (to control AC ON/OFF)
• Voltage and Current Sensors (INA219 or ACS712)
• LCD/OLED Display or Wi-Fi Interface
• Miscellaneous: Fuses, Switches, PCB, Cables
4. System Overview
The system operates by converting solar energy into electrical power using photovoltaic panels. This power is regulated by a charge controller, stored in batteries, and then converted into AC using an inverter to power the air conditioner. A microcontroller monitors room temperature and toggles the AC using a relay.
5. Solar Power System Design
• Calculate power requirement of AC (e.g., 1 ton ≈ 1200W).
• Estimate daily energy use (e.g., 4 hours/day → 4.8 kWh).
• Select solar panel capacity accordingly (e.g., 800W panel × 6 hours = 4.8
kWh).
• Choose appropriate battery bank size (e.g., 12V, 200Ah for 2.4 kWh storage).
• MPPT charge controllers optimize charging efficiency.
6. Air Conditioning Control Logic
• Temperature sensor monitors room temperature.
• Microcontroller compares measured temp with threshold (e.g., 26°C).
• Turns AC ON if temperature > threshold and sufficient battery voltage.
• Turns AC OFF if temperature < threshold or battery low.
• Optional: Use RTC for time-based scheduling.
7. Battery Storage and Power Management
• Batteries store excess energy from solar panels.
• Voltage sensors monitor battery level.
• System disables AC during low battery conditions.
• Inverter should be sized to handle peak AC current draw.
• Include overcharge and deep-discharge protection.
8. Circuit Diagram and Integration
• Solar panel → Charge controller → Battery bank → Inverter
→ AC unit.
• Microcontroller powered from regulated 5V source.
• DHT22 sensor connected to digital pin.
• Relay connected to microcontroller output to control AC switch.
• LCD/OLED for displaying temperature, voltage, system status.
9. Software and Microcontroller Code
Sample Pseudo Code:
#include <DHT.h>
#define DHTPIN 2
#define RELAY 3
DHT dht(DHTPIN, DHT22);
void setup() {
pinMode(RELAY, OUTPUT);
dht.begin();
}
void loop() {
float temp = dht.readTemperature();
if (temp > 26.0) digitalWrite(RELAY,
HIGH);
else if (temp < 24.0)
digitalWrite(RELAY, LOW);
delay(5000);
}
10. Applications
• Residential solar-powered HVAC systems
• Smart buildings and green homes
• Off-grid cooling systems
• Rural areas with unreliable power supply
11. Challenges and Future Enhancements
• Initial cost of solar infrastructure is high.
• Requires precise energy budgeting and battery sizing.
• Enhancements: Smart energy analytics, IoT control, remote diagnostics,
AI-based adaptive cooling.
12. Conclusion
The Solar-Powered Air Conditioning System offers an environmentally sustainable and cost-effective alternative to traditional cooling systems. Leveraging embedded electronics and renewable energy, it serves as a strong foundation for green technology innovations.