Freezer to Refrigerator Conversion
Introduction
Convert a freezer to a refrigerator, and reduce energy consumption 12x so that your refrigerator uses 8 Watts of average power.
This translates to about 50 million megawatt hours of electricity (126M households with 1 fridge) saved per year in the USA if everyone converted to an energy saving fridge from a 1kWhr/day scenario today. This is about $5 billion dollars saved per year in America.
Nearly every household on Earth has a verticaldoor fridge that uses 100W of power on average - or about 2.4 kWh per day. In a country of a few million households, replacing vertical door refrigerators with chestfridges can save enough energy to allow closing down at least one large power station. Alternatively, construction of a new power station to meet the increasing energy demand could be avoided or delayed. http://mtbest.net/chest_fridge.html
In money terms, the Superfridge costs 2 cents per day to run (assuming 10 vent per kWh electricity cost). This is about $7 per year - compared to $88 for an average fridge.
For the Seed Eco-Home, the cost is actually even better. The off-grid energy system cost $3000 for 3kW not including labor. This translates to 2 cents per kWh energy cost over a 20 year life of the PV system. That is about $1.50 electricity cost to run the refrigerator for a whole year!
Original Work
This work is based on the Mt_Best_Freezer_to_Refrigerator_Conversion.
Wiring Diagram
Wiring Harness
BOM
sparkfun
- Sparkfun Pro Micro 3V - $19.95 sparkfun - Install Instructions
- Arduino MKR1000 WIFI sparkfun
- 24-280VAC Relay - $9.95sparkfun
- or SainSmart Relay Module $3.99 - Requires 5V Board
- Thermister $0.75
- 10k Resistor $0.95
- Female Headers
- Jumper Wires M/M
- USB 5V Charger $3.95
- USB Micro Cable $1.95
- Junction Box $7.23
- Twin-screw cable clamp HomeDepot
- Extension Cord - Ace Hardware
- 2 Conductor Speaker Wire - Ace Hardware
amazon
- Sparkfun Pro Micro 3V amazon
- Relay amazon
- Themister amazon $4.32
- 10K resistor amazon
- Female Headers amazon
- Jumper Wires M/M amazon
- USB Wall Charger 1A 5V amazon
- 4"x4"x4" Electrical Junction Box amazon
- 120V Male Receptical amazon
- 120V Female Receptical amazon
- 1-11/16 Hole Saw amazon
- Extension Cord amazon
- Lighted End Extension Cord amazon
- 2 Conductor Wire amazon
Arduino Code
//A1 read voltage
//D3 sensor power
//D14 relay (-)
volatile int sensorvalue = 328; //define the variable
int triggeron = 328; //number that will trigger fridge on
int triggeroff = 304; //number that will trigger fridge off
// the setup function only runs once every time the chip is reset
void setup() {
digitalWrite(3, HIGH); //for powering thermister
digitalWrite(14, HIGH); //for switching relay
pinMode(3, OUTPUT); //begin operating pin
pinMode(14, OUTPUT); //begin operating pin
delay(20000); // wait for thermister to get a good initial reading
}
// the loop function runs over and over again forever
void loop() {
sensorvalue = analogRead(A1); //read sensor
if (sensorvalue > triggeron){ //if sensor reads over triggeron, turn on
digitalWrite(14, LOW); //turn on relay
delay(8000); //wait 8 seconds
}
if (triggeroff > sensorvalue){ //if sensor reads below triggeroff, turn off
digitalWrite(14, HIGH); //turn off relay
delay(8000); //wait 8 seconds
}
}
- See Talk:Freezer to Refrigerator Conversion for explination of trigger values.
Other Options
- http://mikeysklar.blogspot.com/p/yatc.html
- https://www.amazon.com/gp/product/B0002EAL58
- https://johnlvs2run.wordpress.com/2009/10/08/chest-fridge-conversion/
