Solar heater with Aluminum cans controlled by Arduino

myminifactory

Solar Heating Using Aluminum Cans - A Contest Entry Based on Personal Study/Project This project aims to repurpose recyclable 250ml aluminum cans to create a solar heater for homes, cottages, shelters, cabins, and garages. The aluminum's thermal conductivity properties make it ideal for this application, as it heats or cools relatively fast depending on the use case. For this project, I utilize the aluminum's heating property by absorbing heat from the sun, which warms the air once circulated inside the cans. Materials Needed: * 250ml aluminum cans with top and bottom parts cut and removed * Printed connectors, elbows, tees, wall-through connectors, ventilator spout, and damper * For the enclosure: wooden or plastic insulated box, glass (tempered preferable) sheet or plexiglass, flexible plastic hoses to run through walls, heat-resistant glue or silicon * Black paint to paint aluminum cans and box interior * Small servo to open/close damper - HITEC 70mg servo used here, but other similar-sized servos on the market will fit the mount * Arduino board with 2 temperature sensors (HDT11 or HDT22), Arduino LCD (optional), and one 5V relay * Computer fan The project involves using aluminum cans with top and bottom parts cut. The cut cans are connected vertically through printed connectors, which are a crucial part of this design as they connect the cans, attach to the enclosure with screws, and help create a circular uprising motion of air inside the column once the air is heated by the sun. The connector design allows for printing without supports and includes three fins inside to create a small air 'vortex' that helps move air efficiently for better heating. I looked at several iterations of can air heaters built on YouTube, which seem to work well in cold areas. Please refer to the attached drawings => The heating is achieved by air movement through aluminum cans due to heating and natural convection created. Cold air is drawn from the lower part of the room, travels through aluminum cans, and as it moves upward, it heats up. Convection helps move air efficiently for better heating. Below is the Arduino Sketch with the following pin connections (please refer to the Arduino pin out image): * The outside temperature sensor will be connected to A1, inside temperature to A2 * Servo to pin 6 * Relay to pin 7 ```cpp #include <DHT.h> #define dht_dpin1 A1 //no ; here. Set equal to channel sensor is on #define dht_dpin2 A2 DHT DHT; int relay = 7; int servoCold = 179; // Angle in which servo will go to int servoHot = 0; // Angle in which servo will go to Servo servo1; LiquidCrystal lcd(12, 11, 5, 4, 3, 2); void setup() { lcd.begin(16, 2); Serial.begin(9600); servo1.attach(6); // Attaches servo to specified pin delay(300);//Let system settle } void loop() { DHT.read11(dht_dpin1); lcd.setCursor(0, 0); lcd.print("Out Temp "); lcd.print(DHT.temperature); lcd.println("C"); delay(800); lcd.setCursor(0, 1); lcd.print("Out Humd "); lcd.print(DHT.humidity); lcd.println("%"); delay(500); DHT.read11(dht_dpin2); lcd.setCursor(0, 0); lcd.print("In Temp "); lcd.print(DHT.temperature); lcd.println("C"); delay(800); lcd.setCursor(0, 1); lcd.print("In Humd "); lcd.print(DHT.humidity); lcd.println("%"); delay(500); if (dht_dpin1 > dht_dpin2) { digitalWrite(7, HIGH); servo1.write(servohot); } else { digitalWrite(7, LOW); servo1.write(servoCold); } delay(500); } ```