Any  product which is meant to be stored in artificial temperatures (25 °C to  -25 °C) to increase the shelf life of that particular product is a part of  Multi commodity cold storage. Various products which are  stored in a Multi commodity Cold Storage are:
(a) Vegetables
(b) Fruits
(c) Spices
(d) Dry Red Chilli
(e) Kirana Items :  Pulses, Lentils, Jaggery, Grains etc.
(f) Potatoes
(g) Dairy Product-Milk, Curd, Cheese, Paneer
(h) Non Dairy product-Whip  cream
(i) Sea food
(j) Frozen food
(k) Dry Fruits
(l) Ready to eat
(m) Ice Cream
(n) Frozen peas
(o) Sweet Corn
(p) Poultry

As per  guidelines, one ton of material requires about 120 cft of space. With the  height available at your site, you may decide on the room size.
A typical Multi Commodity cold  storage would require about 12000 sqft area (only storage space) with height of 50 ft (5 floors). In totality you might need  approx 24000 sqft for a project of 5000 MT

The following is our recommendation:
(a) For Total Cold Storage size of 2500 MT and below, you can  prefer Freon
(b)  For Total Cold Storage size of 2600 MT and above you can  prefer Ammonia            
● Capital Cost is almost the same for both
● Operational cost for Ammonia is lesser when compared to Freon  for 2600 MT & Above
● Automatic Running of machines is beneficial and requires no maintenance for 2500 MT & below since no operator is required

The following parameters are required to design refrigeration system for a multi commodity cold storage:
(a) No of bags per chamber
(b) No of chambers
(c) Outside Temperature
(d) Weight of Each Bag
(e) Total Storage Capacity
(f) Chamber Size
(g) Loading Temperature
(h) Loading Rate
(i) Air Cooled / Water Cooled
For  a typical 5000 MT Multi commodity Cold Store of 4 chambers, the refrigeration capacity required is approximately 120 TR @ -5°C evaporation temperature.

There are various ways total electricity consumption can  be saved:
(a) Proper insulation & Insulation thickness
(b) Proper selection of Indoor Units
(c) Roof Insulation
(d) Leakages in Insulation

Indoor Unit is approx 25% of the total electricity consumption in a cold Storage. Following are the parameters that affects electric consumption:
(a)  Choosing the right Pitch (square pitch) of the evaporator plays  a major role
(b) Since the other factors like compressor, ammonia pump & condenser pump are all fixed the only way to save electricity is through  Right Selection of Indoor units only
(c) The right balance of pitch, surface area, air volume & tube volume in the indoor unit will help in saving electricity

There are various factors which need to considered at  the time of designing a Potato Cold Store unit
(a) Air Volume - Total Air Volume should be minimum of 85 cmh per  Ton of material during Loading period at static of 100 psi
(b) Surface Area - Total Surface Area of the Evaporator
(c) Air Throw - Should be minimum or more of the room length or  width (depending on the side in which the units are placed) (d) Relative Humidity - Unit should be designed optimally to give  adequate Relative Humidity in the Chamber
(e) Fin Spacing - Should be 4 FPI or 6 mm
(f) Fan kW or Hp - To be considered while designing the Unit
(g) Pitch of the Evaporator - Square Pitch. Best Design to have  less Pressure Drop and better efficiency and as a result Lower power  consumption

These  factors can affect the following in the Cold Store:
(a) Electricity Consumption
(b) Quality of product
(c) Weight loss
(d) Avoiding creation of Hot spots
(e) Optimum utilization of space in the cold storage

Air Flow  plays a major role in the quality of the product. If the Air Flow is not  adequate in the room, there will be a potential of creation of hostpot inside  the chamber & possibility of reduction of shelf life of the product. To avoid Hotspot Creation  inside the room (like corners, bags kept at the end of the chamber) air flow  plays a major role.

Selection of right indoor & various factors in Selection of Indoor - Answered in question 7

A typical  multi commodity cold storage would cost approximately between Rs. 10,000/- per  MT to Rs. 18000/- per MT for a minimum of 5000 MT (excluding land).