Smart Fridge: Connectivity to Sustainability
St George's School
Floor Location : J 013 N
Many refrigerators in the world use unnecessarily high amounts of power, as they often reside in heated rooms. They are the fifth highest consumers of energy in the average household.
Low energy fans can be used to supply cool outdoor air to a refrigerator when needed, thus reducing the usage of the high energy consuming air compressor within the fridge.
By using a palm-sized $35 computer known as a Raspberry Pi (RasPi), an energy-saving refrigerator has been created. The RasPi turns two fans connected to the fridge on or off and changes the temperature within the fridge when certain temperature parameters are met. Whether it is necessary for the RasPi to turn the fans on or off is deterred by a Python script written for it that refreshes every 1.5 seconds. This is connected to two General Purpose Input Output (GPIO) temperature sensors, one inside the refrigerator and one outside, as well as a device called YKUSH which is a USB Hub controllable by a script written for the RasPi. This is connected to two 3cm fans - one for intake and one for output of air. The energy consumption of the refrigerator will be reduced because the combined usage of the RasPi and YKUSH is under 5 volts and 2 amps. The unit indicates when it is using reduced power via the fans by turning on a green LED light. As most refrigerators run 24/7, whenever the outdoor temperature is optimal this system should lower energy usage and, therefore, put less pressure on power plants and ultimately on the environment.
It is not economical to have a refrigerator in a heated room when, in a cold climate, cool air is just on the other side of the wall. By simply connecting simple, inexpensive components and programming a Python algorithm that calculates whether to turn on the fans and LED, energy and cost savings can be realized.
The hypothesis that low energy fans can be used to supply cool outdoor air to a refrigerator when needed, thus reducing the usage of the high energy air compressor, was proven correct. This is an important project because of the potentially for scalability for domestic and commercial applications. It is, however, limited to applications in cold climates.