Within the scope of this assignment, each student is responsible for investigating an ordinary household refrigerator in their homes/dormitories, estimating the coefficient of performance (COP) of that over a specific period based on simple measurements and investigating the associated ideal and actual refrigeration cycles and irreversibilities. The coefficient of performance for refrigerators is simply the division of the heat removed (Qc) from a cold reservoir (inside a refrigerator) by the work done by the compressor (W) to remove the heat. COP ideal Tc Th-Tc COP a actual where; Qe: heat removed from the cold reservoir (evaporator load) W: total work supplied to the refrigerator (compressor work) Te: the temperature of the cold reservoir Th: the temperature of the hot reservoir For calculations in terms of total energy, Qc and W will be expressed in Joules. In case you use the rate of energy, the unit should be in Watts using Qc and W with time-averaged quantities. In either case, the total observation period (or experiment interval) needs to be defined, and the same duration must apply to the data collection of both Qc and W (or Qc and W). The longer the duration, the more meaningful the data becomes since one should expect substantially different day and night use behavior of a refrigerator. A 24-hour interval, therefore, is a good choice. A few tips below will help you in the preparation of the project; W is electrical energy. The refrigerator will not run for 24 hours. Hence, assuming that all electrical work is used by the compressor, data can begin to be collected by recording the duration and frequency of the compressor operating behavior through auditory observation. The power you will calculate will be the maximum power consumed by the refrigerator. When calculating Qc, remember that the refrigerator is at a relatively constant temperature. On the other hand, there will be heat sources such as food in the refrigerator. Also, take into account the mass transfer that will occur during the opening and closing of the doors and heat transfer through the insulation material.