FREEZER STORE OF THE FUTURE
Faced with the business disruption of the Covid – 19 shutdown, we decided to look into the possible future of what cold & freezer stores could look like within the next 10 years. The concept was directed more to the economic adoption of new features as they are all currently in use & even standard practices globally.
It is ironic that none of the proposed improvements are yet to be invented. All of them are available and, if incorporated into cold storage design, I argue that they would decrease current average energy costs by at least 60% while improving operational efficiency by a similar percentage. Although there would be an initial capital cost, it would be a gift that kept on giving for the life of the freezer store.
We created 3D illustrations that feature links to articles that Barpro Storage has published in the past. The articles bring attention to some of the suppliers that provide solutions within the industry.
* The freezer store is orientated to have the largest possible roof area in direct sunlight for the maximum hours per day.
* Other roof areas including the airlock and walls with direct sunlight are painted with heat retardant paint.
* The roof covering facing the sun is made from interlocking PV panels to supply the freezer store with approximately 30% of its power requirements.
* The roof gutters are made from galvanized steel and over-sized. All the down-pipes lead to a rainwater storage tank which is also used to collect water from the evaporator pods on defrost. All the water collected is filtered, passes through an ultraviolet attachment to kill bacteria, and is used in the cold store offices, the refrigeration condensers, and the glycol underfloor heating.
* The evaporators inside the room are in closable pods to prevent heat transfer to the product during defrosts.
* The freezer box sandwich panel is 200 mm thick and the insulator is a closed-cell foam with at least a two-hour fire rating. The sandwich panel joints are such, that they form a completely airtight seal. Over insulating the ceiling and walls cuts down on heat transfer into the room and reduce energy costs. The freezer store’s clear height is a maximum of 15 meters. The ceiling panels are at a 2% angle from the center point outwards to allow any moisture to run off rather than to pool in the roof void.
* The bottom 3 meters of the side walls are cladded with perforated IBR sheeting to allow for better air circulation around the freezer box. The roof void is ventilated on the non-PV panel side with rotating ventilators of the whirlybird type.
* The refrigerated trucks are held in place with truck locks and only released once the load is locked and sealed and the paperwork completed. This system prevents trucks from leaving the dock with materials handling equipment and personnel still on board.
* The health hazards of working in cold rooms without proper protective clothing can be divided between the short and long term. Risk occurs not only when a person is working in cold temperatures, but also when they move between one temperature regime and another.
CLICK ON THE ARTICLES RELATED TO ILLUSTRATION 1:
* The top level of racking beams have phase change material units protected within their depth. No storage space is lost, but the phase change material absorbs heat more quickly during the day than the frozen product when energy costs are high and releases it at night in cheaper energy periods when the refrigeration system is programmed to reduce temperatures. Savings from phase change technology in freezer stores can save 30% of previous energy costs.
* The freezer room lights are LED and each fitting has its own ceiling mounted plug and is rail mounted to allow for easy maintenance. The lights stay on in the gangway but only come on in the open aisles to save power and reduce heat.
* No matter the size of the room there is only one access door for a product which is as low as possible. The access door has an airlock which is kept at positive pressure by means of a dehumidifier. doors into an out of the airlock are of the high-speed foam insulated type. There is a separate access door for the reach trucks which has a roll-up foam-insulated door. installing the best door technology stops warm moist air from entering the freezer. Through sublimation, this moisture will end up insulating the evaporators and reducing their performance.
* All reach trucks and man on riders are powered with fuel cell technology so that the energy requirement of recharging batteries is removed.
* Fire is prevented inside the freezer box by means of an oxygen reduction system. This prevents fires from ever starting , removes the risk of accidental sprinkler discharges and associated damage to product stored.
* The freezer room also has a multilevel mezzanine where pallets from the mobiles are deposited for case picking. It brings the product to the pickers and efficiency is improved. The pickers use a voice-activated picking technology and wear protective clothing that allows them to work in comfort for extended periods.
CLICK ON THE ARTICLES RELATED TO ILLUSTRATION 2:
* As an alternative to the access door there are two chain-driven pallet conveyors. They also have separate airlocks with smaller foam doors and dehumidifiers. The conveyors can allow the work rates in the freezer and on the airlock to be different as they create a magazine effect. They can also allow for dual cycling where the reach truck driver can have a pallet on his forks when both entering and leaving the mobile racking.
* The ground floor of the multi-tier mezzanine is used for order make up in reverse drop sequence. The loads are only taken out of the freezer when a refrigerated truck is ready to load. This allows the airlock floor area to be reduced
Article linked to Illustration 3
Our dreams will differ from yours. We would hope that our attempts to articulate our dream about cold stores will inspire comments, critical or otherwise, as well as suggestions which we have overlooked. These can then be used to generate a wide range of discussions in upcoming newsletter issues.