Refrigerator and its Performance

 Refrigerator is a device which is used to remove heat from a cold system.

REFRIGERATOR AND ITS PERFORMANCE

Refrigerator is a device which is used to remove heat from a cold system. In other words, it is used to maintain the temperature of the body lower than the surroundings. Example: Air conditioners, coolers, freezers etc.

The efficiency of a refrigerator is expressed in terms of the 'Coefficient Of Performance' (COP). It is the ratio of heat extracted to the work input.

COP of a refrigerator is given by

where T3 and T4 are high and low temperature of reservoirs respectively.

Note that the value of COP can be greater than unity. It is opposite to thermal efficiency which can never be greater than 1.

Missing 2.5

1. Ways to Minimize Energy Consumption in a Domestic Refrigerator

(i)

(ii)

The temperature adjustment and air temperature in the room determine the duty cycle of refrigerator. So, the power consumption in the refrigerator will be high in summer season and if it is kept in kitchen.

A double door refrigerator should be used because the freezer compartment is not frequently opened. When it opens frequently, there will be more power consumption.

(iii) The temperature should be wisely set. There are mainly three temperature adjustments for the seasons such as normal, cold and summer seasons. The knob should be accordingly set.

(iv) The gasket should be checked. It is a rubber lining on the door. If it is loose or broken, fridge will continuously switch on because the inside temperature rises.

(v) The refrigerator should be kept in a well-ventilated area with minimum 30 cm gap from the wall.

(vi) The compressor and coil should be cleaned once in a month.

(vii) Voltage drop is the most common cause of increased power consumption in refrigerator. When the voltage drops, current use will increase. So, the line voltage should be checked.

(viii) Always hot food should be cooled to room temperature before storing in the fridge/freezer. Since the hot food would take in the cold air from the fridge causing the unit to work hard in order to maintain its temperature.

(ix) The vegetables should be kept in polythene bags which will reduce the power consumption of refrigerator because there will be some cold air inside the bag which keeps the vegetables fresh.

(x) Unless the noticeable condensation, power-saver switch on the energy-saving setting should be kept on.

(xi) Refrigerator door should not be unnecessarily opened. As every time it is opened, some heat enters which will increase the power consumption.

(xii) The refrigerator remains tightly closed when not open. Any open space will cause heat to get into the refrigerator causing motor to work harder thereby consuming more electricity.