How do you calculate the work reqd for freezing meat from normal temperature? What would be the capacity of a freezer to freeze 1500 kg. meat? 
For water it's 1 Kg = 1 litre. Meat is around 75% water. So for most foods you can roughly say 1 Kg = 1 litre. Give or take some, plus packaging materials and voids in packing  So 1500 Kg meat is going to be up to 2000 to 3000 litres!  Freezers compressors are rated by their ability to cool quickly only at much smaller capacity than the total capacity of the freezer. e.g. A typical 350 l freezer would only be able to cool 30 ish Kg of fridge cold meat to frozen in a day, many freezers are not even this good!  Racks and shelves help with uniform cooling, but shifting 1500 Kg of meat from 4°C to -20°C is going to take some serious work  Roughly; shifting 1 Kg of water -20C uses about 1.4 KW of heat removal. So 1500 Kg is 2100 KW. A freezer is 2.5 to 3.5 efficient due to heat pump, so 2100 KW / 3 = 700 KW of electricity. Your typical domestic freezer is rated at 1 KW, so it's going to take 29 days to freeze! 