Cold storage Design and costing

I have been handling the cold storage (Cold room) business for a private company. Cold storage (Cold room) design has the simplest practical way rather than the theoretical way. We use theory but there is a difference between theory and practical. In this blog I will be focusing on the practically proven way of designing the cold storage (Cold room), getting it manufactured and executing the same with help of contractor if you are new in the business and have no manpower for the execution of the same. I will try to explain step by step procedure to make cold storage (Cold room) on our own.

To design a cold storage (Cold room) we need some basic information as follows. I have one questionnaire to collect the information.

1- What temperature is required for the cold storage?

Pre-cooling chamber:  Positive temperature used for pre-cooling, in the range of 0/+ 8 °C.
Cold storage room (cold room): Positive temperature for used in the range of + 8/+ 14 °C.
Cold storage chamber: In the range of  -1/+ 8 °C
Frozen storage chamber: Negative temperature for the preservation of frozen products in the range of -18/-24 °C
Blast freezing chamber: In the range of -35/-45 °C used for the blast freeze .

2- What is the product to be stored?

Different product can be stored in one cold storage in it is in packing else use cold storage (Cold room) for one product

3- What is the incoming temperature of the product to the warehouse?

Incoming temperature of the product is crucial to design the refrigeration system. The higher temperature of incoming product, the more cooling capacity is needed.

4- What is the pull down time required?

Pull down time means time to bring product temperature down to design temperature from its incoming temperature

5- What is entry amount to the warehouse of the products every day?

Knowing the entry amount of product is important in the calculation of refrigeration system capacity. As it involves new product quantity and temperature, operation of forklift, number of employees entering in the cold room.

6- what is the size of Cold storage?

Cold storage dimensions

7- what is the ambient temperature?

Outside ambient temperature plays an important role in designing the cold storage refrigeration.

8- what type of Door required?

Swing Door or Sliding door.

9- what door accessories required?

Door accessories like, Door handle, Door lock, Door hinges, Door closer.
10- What type of flooring required?

Flooring like, aluminum checkered plate or Puff slab with tarfelt sheets.

Once we get all above information then we can design the cold room and can give estimated price to customer including our margin. Let us see how to make an estimation.

We will take one case or example.

As per above questionnaire following are the requirement customer has placed with us.

Sr. No.	Description	Customer's requirement
1	Cold room size	10ft x 10ft x 8ft Height
2	Required temperature	20 C
3	Product	Vegetables
4	Incoming temperature of the product	10 degree
5	Pull down time	8 Hrs
6	Entry amount of product everyday	1500 Kg
7	Ambient Temperature	450 C
8	Type of Door	Sliding
9	Flooring type	Aluminum checkered plate

 

1.      Panel size and price calculation.

I always refer one excel sheet for the calculation. Please refer following excel sheet. I will share a video on the same how to calculate panel pricing. Its approximate calculation. In my case it is exact as I have fixed the prices with my vendor, but these prices are almost same with 5% to 10% tolerance.

P U F   T H I C K N E S S / T E M P
Temperature range	Puf panel thickness
00 C to 100 C	60mm
00 C to -50 C	80 to 100mm
-50 C to -250 C	120mm
-250 C to -400 C	150mm

Design Parameters:
A.	Product: Vegetables
B.	Incoming Temperature: 15
C.	Pull down Time: 8 Hours
D.	Insulation thickness: 60 mm PUF
E.	Ambient: 45°C
F.	Total load: 1500 kg
G.	Material Turnover per day: 1000 kg
		10	10	8
External Size  (2°C) :   3.05 x 3.05 x 3.05 mtrs
External Room Size in Meters		Length	Width	Height
		3.05	3.05	2.44
Wall and Ceilings Panel Area (m²)			37.40
Floor Panel Area (m²)			9.29
PUF Panel Thickness (mm)			60
Sr. No	Description	Qty	Rate	Amt
		( m²)	Rs/( m²)	Rs
1	FB 60 mm PUF Panel 0.5mm with GIPP/GIPP skin and with average density of 40kg/m³	37.40	1,432.50	53,574.46
	for Walls and Ceilings with cam lock.
2.a	FB 60 mm thick PUF Slab with Tarfelt Sheets	9.29	1,150.00	10,683.85
	on both sides
	OR
2.b	FB 60 mm thick PUF with GIPP outside, 12mm Marine	9.29	2,432.00	22,594.02
	Ply + 1.2mm chequered plate inside
3	FB 60 mm Door size: 900x1800 mm SS/GIPP	1	22,000.00	22,000.00
	with KASAN type Indian Hardware and accessories.
4	Lights	3	750.00	2,250.00
5	Installation Accessories such as angles,	46.69	200.00	9,337.92
	flashers, rivets and silicon sealants etc
6	Installation Labour( Within Mumbai)	46.69	0.00	0.00
Total (with PUF Slab)			Rs	97,846.23
Total (with Chequered Plate Flooring)			Rs	1,09,756.40

 Puff panel prices (All prices are from my vendor, Do not take it as a bench mark, price may vary as per location and supplier of puff panel)

PRICE LIST FOR PUF PANELS WITH VARIOUS SKIN MATERIALS AND GI / PLASTICS CAM LOCKS
Thickness of Skin & skin material	Thickness of PUF	MRP (INR/ M2)	Discounted Rate	Discounted Door Rates for the same Finish
0.5 mm Pre-Coated both sides	60 mm	1910.00	1432.50	22000.00
0.5 mm Pre-Coated both sides	80 mm	2065.00	1548.75	24000.00
0.5 mm Pre-Coated both sides	100 mm	2465.00	1848.75	29000.00
0.5 mm Pre-Coated both sides	120 mm	2630.00	1972.50	32000.00
0.5 mm Pre-Coated both sides	150 mm	2890.00	2167.50	35000.00
0.5mm Pre-coated  one side & 0.6 S/S one side	60 mm	3050.00	2592.50	25000.00
0.5mm Pre-coated  one side & 0.6 S/S one side	80 mm	3200.00	2720.00	27000.00
0.5mm Pre-coated  one side & 0.6 S/S one side	100 mm	3615.00	3072.75	31000.00
0.5mm Pre-coated  one side & 0.6 S/S one side	120 mm	3785.00	3217.25	34000.00
0.5mm Pre-coated  one side & 0.6 S/S one side	150 mm	3925.00	3336.25	37000.00
0.6mm S/S both sides	60 mm	4150.00	3735.00	27500.00
0.6mm S/S both sides	80 mm	4365.00	3928.50	29500.00
0.6mm S/S both sides	100 mm	4670.00	4203.00	34000.00
0.6mm S/S both sides	120 mm	4840.00	4356.00	36500.00
0.6mm S/S both sides	150 mm	4990.00	4491.00	39000.00
Flooring Rates
PUF Slabs with Tarfelt (Civil work to be done by customer)	60 mm	1100.00	950.00
	80 mm	1300.00	1150.00
	100 mm	1500.00	1350.00
	120 mm	1700.00	1550.00
	150 mm	1900.00	1750.00

 

2.      Lets calculate the required cooling capacity. To calculate cooling capacity we need help of some apps like Igloo or Alfa Laval’s cold Room calculator. There are number of cold room calculators are available all are free and easy to use. Let us consider Cold room calculator from Alfa Laval.

Please click on following link to see the cold room heat load calculation

Watch video how to use Alfa Laval cold room calculator

Once you calculated the cooling capacity in kW or Btu / hr we can select a suitable compressor. Basically I prefere following compressor brand for the coldrooms.

·         Tecumseh

·         Emerson

·         Frascold

·         Bitzer

·         Danfoss

For this particular case we will consider Emerson compressor. As per the capacity calculation Cooling capacity is 2.8 kW. Let us see how to select the compressor.

Please click on following link to see how to select compressor.

Watch video how to select compressor as per required capacity

Once we are done with all calculation work we can prepare costing. I have one simple format for costing as follows.

Description	Amount In INR	Remark
Panels Price	1,09,756
Refrigeration unit price	50,000	I have considered it as per current unit
Refrigeration installation	25,000	Approx. Rs. 25000 / Unit
Puff Panel Installation	8,000	Approx. Rs. 150 / Sq. Meter
Control Panel price	5,000	For positive temperature
Extra material required	3,000	Like Expansion valve
Service	8,000	1-year free service
TOTAL COST	2,08,756
Price Of Cold Room	2,80,000
MARGIN	25%