The storage systems best suited to your refrigerated store (part II)

Designing a storage solution for a controlled temperature facility requires an experienced partner in fitting out this type of warehouse, not only due to the type of goods to be stored, which tend to be perishable food or pharmaceutical products,  but also because this type of refrigerated storage facility presents a series of conditioning factors that require the use of specific storage solutions to minimise the energy cost of refrigeration, optimise the space, improve access to the load, and facilitate the work of the warehouse operators.

Based on the needs of the project, we will choose one storage system or another, or even install different complementary racking systems.

When it comes to choosing the type of industrial racking best suited to our refrigerated store, it must meet certain conditions:

• Optimise store volume.
• Maximise storage capacity.
• If there is a risk of rust or corrosion, fit out the store with galvanised shelves for increased strength and useful life.
• Facilitate access to load units.
• Avoid unnecessary movements of operators at low temperatures.
• Speed up loading and unloading operations.

Calculate the energy consumption per load unit

In designing a storage system, use of the volume is always a key factor to be considered for the solution to be successful. However, when storage is in a refrigerated facility, this becomes even more important because of the fixed energy cost required to keep the cold temperature constant within the store.

How do we calculate a refrigerated store’s energy consumption per pallet?

Using this formula you can find out the daily energy cost per pallet of your store at maximum occupancy. Plus, if you need to decide between two or more storage solutions, you can apply this formula to calculate what the future daily energy consumption cost will be for each possible solution. This will help you to identify the most energy-efficient solution in the long term. And in turn, the solution with the lowest environmental impact for the growth of your business.

Recommended cold storage systems

Cold stores can be installed using any type of storage system; however, among the available options, some have features that make them more suitable for this type of environment. Different storage systems can also be combined in the same cold store.

Clad rack cold storage facility

A clad rack warehouse has a dual function:

– fit out the warehouse with the required storage solution for the case and modus operandi of the goods

– build a self-supporting facility where the racking supports the structure of the building’s enclosures and the total load of the goods

The roof and facades of a refrigerated clad rack warehouse are built using sandwich panels. This material has an excellent insulation capacity and provides a good seal against moisture and damp.

A clad rack warehouse is principally fitted out with racking and automated systems such as forklifts and miniloads, or semi-automated systems such as the shuttle.

Advantages of building a refrigerated clad rack warehouse:

• Optimises surface and height space
• Does not require civil works.
• Saves costs on buying or constructing a building.
• Perfect thermal insulation, sealing, and self-supporting capacity thanks to the sandwich panelling.

Automated cold storage facility

Automated pallet racking warehouses with stacker cranes, or miniload AS/RS warehouses for non-palletised goods, operate automatically using robotised load-handling equipment.

Advantages of a refrigerated warehouse with stacker cranes or miniload AS/RS:

• Avoiding warehouse employees being exposed to low temperatures, as the robot handles the goods.
• Optimising the surface, as the required width to access loads is narrower.
• Storing loads at great height, maximising utilisation of the storeroom volume.
• Saving on energy costs.
• Quick load location and handling operation.
• As it is a compact warehouse, the yield of cold generating equipment is optimised.
• Thermal changes are prevented by reducing the number of times required to open/close entrances/exits.

This type of solution is best suited to cold logistics, as it makes maximum use of the warehouse height and volume, allows loads to be stored compactly, and maintains uniform temperature conditions throughout the cold store.

Semi-automated cold storage facility

Another storage solution recommended for refrigerated environments is partial automation of some of the load handling processes.

This automation involves adding a compact storage system, using shuttles in charge of moving the goods within the shelving aisles.

Advantages of fitting out a refrigerated warehouse with shuttle racking:

• It avoids operators having to enter the aisles to load/unload pallets, achieving:

1. 1. Saving load-handling time.
   2. Avoiding damage to the racking through accidental collisions of operators in the aisles.
   3. Reducing accidents for persons in charge of the handling equipment.
   4. Lowering operator exposure time to low warehouse temperatures.

• Increasing the yield of the surface compared to other conventional storage systems as it is a high-density storage system.
• Speeding up load-handling.
• The shuttle is designed to operate in installations with different pallet width and depth dimensions. Multi-pallet system.
• The shuttle can work at both room and refrigerated temperatures as low as -30 ºC.
• Able to operate in FIFO and LIFO mode.

Drive-in/Drive through cold storage facility

Compact solutions such as the drive-in/drive through racking system improve the power consumption ratio per pallet stored. If warehouse management involves handling a large quantity of pallets per reference, this is an adequate storage solution for controlled-temperature products as it saves space on account of it being a storage system by accumulation. This is one of the non-automated solutions in highest demand for freezer and cold stores.

If the system is designed correctly, creating as many aisles as there are references, load handling times are shortened.

This system also offers structural elements such as the pallet centring rail and rail guide that facilitates load handling and unloads from the compact block. This helps to reduce the times operators are required to remain inside the low temperature storage facility.

Advantages of fitting out a refrigerated warehouse with drive-in/drive through racking system:

• Maximises the yield of store room volumes.
• Reduces the number of access aisles to the racking.
• The storage capacity is greater than with a conventional system.
• Reduces load handling times.

Cold warehouse with mobile racking

If an automated or semi-automated system is not chosen, or it is impossible to use a compact storage system due to the number of references to be handled, warehouse operation, etc., another interesting solution for fitting out a cold storage facility is to install a conventional pallet racking system on motorised mobile platforms.

This type of solution involves installing adjustable pallet rackings on motorised mobile platforms that move the racks. It offers considerable savings in space compared to a conventional warehouse. With just one corridor, it provides unitary access to each pallet. In this way, we convert a conventional warehouse into a block warehouse making the most of the benefits of both systems.

Advantages of fitting out a refrigerated warehouse with mobile pallet racking:

• It converts a unitary access system to each pallet into a high-density compact system.
• Major savings in surface by using the single-aisle space to access all rack rows.
• Optimum cold distribution between stored pallets, guaranteeing product preservation.
• Mobile racks have the option of night parking. When this mode is activated, the racks are all automatically positioned for uniform space distribution between the aisles. This provides improved air circulation between all products stored.

Conventional cold storage facility

The storage system of adjustable pallet racking is the most widespread for dry goods warehouses, but can also be used for controlled temperature stores.

This system does not provide specific advantages for a refrigerated goods facility beyond the characteristics inherent to this solution, such as unitary access to all pallets. It is the most versatile and modifiable solution, and the most affordable choice in terms of the initial investment.

In this system, shelves can be installed on the lower levels for storing non-palletised goods and manual handling or picking, if required by the company’s logistics activity.

Manual picking solutions in refrigerated storage facilities

If to guarantee the cold chain, order preparation or picking tasks cannot be performed in the ante-room and must be prepared inside the cold store, a zone will have to be allocated for this purpose during design of the layout.

Normally, warehouse picking is performed at ground level. This leaves an empty unused space between the floor and the roof of the building. This space, in the case of refrigerated and freezer warehouses, must be cooled even if unused. Therefore, to make the most of the refrigeration cost, we can reduce the surface used for consolidation tasks, and gain space by building tiers designed for this purpose, or use the space above the order consolidation zone to create storage space.

The most appropriate solution for picking tasks in refrigerated stores are multi-tiers or mezzanines. Vertical solutions that seek to maximise capacity. Circuits can be arranged across the different tiers to facilitate operator routes while consolidating the order.

Advantages of multi-tiers or mezzanines in refrigerated stores:

• Increases the m2 used for order preparation tasks.
• Makes the most of the building’s height.
• Improves the cost-effectiveness of store refrigeration costs.

How do I choose the most appropriate racking system for a refrigerated warehouse?

Choosing the right storage system or systems for a controlled temperature facility requires a preliminary study, due to the number of aspects to be considered to optimise the ideal storage solution for each company.

In this type of project, the experience in designing layouts of the racking manufacturer or engineer is important, as an inadequate choice of storage solution can disguise a long-term financial cost that may not be reflected in the initial investment.

Here are some of the most important aspects we must take into account when it comes to choosing our industrial racking system for refrigerated storage:

• Financial criteria such as the initial investment, payback period, and total storage capacity.
• Load-handling time criteria.
• Environmental criteria such as medium/long-term energy saving, carbon footprint reduction, etc.

This post provides you with more information about cold logistics and how to achieve an energy-efficient warehouse.