30 tons of ice At 0°C it’s produced in a day of 24 hours by an ammonia refrigerator . The temperature range in the compressor is from 298 K to 258 K the vapor is saturated at the end of the compression and expansion valve is used assume a coefficient of performance of 60% of the theoretical calculate the power in kilowatts required to the compressor .latent heat of ice is 334.72 kJ per kilogram