By Eamonn Ryan
One of the most significant changes in the refrigeration industry is the shift from HFCs (hydrofluorocarbons) to HC (hydrocarbons) gases. This transition is making waves across both
cold rooms and display freezers.
racking systems’. All images © Cold Link Africa
As businesses and retailers strive to meet stricter environmental regulations and enhance energy efficiency, the adoption of HC gases is becoming a game-changer. Cold rooms, essential for preserving perishable goods, and display freezers, crucial for showcasing products, are both benefiting from this shift. HC gases not only offer a more sustainable alternative with lower global warming potential but also contribute to improved operational efficiency. As the industry embraces this transformation, the future of refrigeration looks both greener and more efficient.
The following presentation was delivered at the 2024 Cold Chain Refrigeration, Logistics and Technology Summit, by James Cunningham, CEO of Barpro on the topic ‘Innovative cold storage solutions with racking systems’.
“Twenty-eight years ago, I gave a speech on mobile racking at a conference in South Africa, where it was generally described as being unsuitable for South Africa. At the end of the speech, one American cold store owner, affiliated with the Global Cold Chain Alliance (GCCA), told me I really needed to get a ‘real’ job as I wouldn’t make any money from mobile racking. Contrary to that early scepticism, that American is today installing mobile racking in his cold stores in the US, demonstrating a significant shift in industry attitudes.
“Barpro has since installed over 400 mobile racking systems mostly in South Africa, each tailored for the conditions with various racking types. I would describe it as a ‘good, qualified success’,” says Cunningham.
“If you want to learn cold storage, visit Australia”
Cunningham took a moment to honour past innovators in cold storage, particularly Fred Tudor (born 1783). Tudor, from the east coast of the US, harvested ice from New England ponds, storing it in special houses and selling it to cities like Baltimore and Philadelphia where the people had a major problem with preserving fresh meat and fruit. He even exported ice to India, achieving the first commercial success with refrigeration.
He also mentioned Cape Town’s first commercial cold store – the Imperial Cold Store and Supply Company building – built by David de Villiers Graaff. This was the first successful shipment of frozen mutton between Australia and England (as well as the first mention of Australia which will be mentioned again). “This marked the beginning of South Africa’s frozen beef exports – today a huge industry. De Villiers Graaff also built Cape Town’s first electricity generator, highlighting the close relationship between cold storage and electricity.”
The modern cold store has been shaped by numerous innovations, with Cunningham pointing out the development of pallets, which evolved from simple skips. “Pallets became essential during World War II, facilitating the movement of military equipment. Following that, surplus pallets in Australia led to the formation of the Commonwealth Handling Equipment Pool (CHEP), which started renting them out standardising pallet sizes. This standardisation became crucial in designing cold storage spaces – and is the building block of racking we all still follow.”
“Thereafter, Dexion steel racking was invented by Demetrio Comino in Australia in the late 1940s. This innovation allowed for vertical stacking of pallets, increasing storage capacity in cold stores. The reach truck, invented in the 1960s, further enhanced this capability by enabling the lifting of pallets to greater heights in narrower aisles.”
Cunningham noted how often wars spur innovation, citing the Vietnam War’s role in advancing containerisation.
Then in the early 1960s Michael Rudnev, an innovator in cold storage in Brisbane, Australia, developed an insulated sandwich panel using chromadek sheeting glued on either side of a polystyrene core. These panels had better insulation properties than cork and were lightweight yet strong enough to support lengths exceeding 10 metres.
“This panel, made from expanded polystyrene, replaced cork as an insulator in cold stores. The chromadek panel improved insulation and structural integrity, paving the way for modern cold storage construction.”
The advent of barcodes in 1974 marked the beginning of computerisation in cold storage. Cunningham shared anecdotes from his early career, including the challenges of real-time stock updates and the use of floppy disks for data transfer physically transported around by motorcycles.
Stressing the importance of affordable energy for cold storage facilities, he acknowledged the role of innovators like Thomas Edison and George Westinghouse in the development of electrical systems that power these facilities.
“Energy efficiency remains a critical issue in the industry, compounded by the dramatic rise in electricity costs in South Africa, which have increased by 500% from 2014 to 2024, and I believe will increase by another 500%. Carbon taxes further complicate the situation, with a need for reliable and affordable energy sources to power cold storage facilities.”
He praised Frank Vale, who integrated various innovations into a model cold store in Dandenong, just outside Melbourne in Australia, in the early 1970s. “That was the first modern cold store.”
Peter Spears, of the UK based Barpro Group was then one of the earlier innovators of mobile racking, along with Dexion. Cunningham explained why mobile racking has been successful: “It maximises storage capacity while maintaining accessibility, is cost-effective and energy efficient. For instance, one British cold store manager reported that doubling storage capacity with mobile racking reduced electricity costs per pallet.
“However, energy costs and reliability remain significant challenges given the high operational costs of running generators during power outages and the critical role of maintaining efficient door operations in cold stores. The industry consequently needs to adopt basic energy-saving measures and leverage available technologies to mitigate these challenges – and the biggest problem in cold storage is the doors, which when left open can typically cost R300 000 a year in energy costs.”
Energy innovations and efficient case picking in cold storage
Cunningham discussed a promising innovation for maintaining cold storage temperatures during power outages: phase change materials. “These materials can be installed under the ceiling of cold storage facilities without taking up valuable space. During normal operations, they freeze and store cold energy. When there’s a power outage, they absorb heat, maintaining stable product temperatures until power is restored. This method could reduce the reliance on diesel generators, which are costly and inefficient. The US company Viking Cold Solutions has been a leader in this area, reporting energy cost savings of about 35%. However, I believe the savings could be even more significant when compared to generator fuel costs during blackouts with some piloting of this technology with a cold storage company to quantify potential savings.”
Cunningham then shifted focus to innovations in case picking within mobile racking systems. Contrary to the belief that mobile racking is unsuitable for case picking, he demonstrated a successful implementation in a Cape Town cold store. By designing a cantilever at the back of the mobile racks, workers can navigate around the back with pallet jacks, allowing for efficient case picking. The store initially had a single picking aisle but found success by doubling the number of picking aisles, further optimising the system.
“A cold store manager once told me that ‘full pallet storage covered his costs, but case picking generates his profit’. This insight emphasises the importance of integrating efficient case picking systems into cold storage operations. Historically in South Africa, case picking and full pallet storage have been carried out in separate stores, but combining them can maximise efficiency and profitability. Properly executed case picking within mobile racking systems allows cold stores to retain the benefits of vertical storage while maintaining easy access to individual cases.”
For high-volume, fast-moving products, Cunningham suggests a multitier mezzanine picking system (the example he used was similar to the system employed at Eskort, featured in CLA July issue). “This system places slow-moving items on the upper levels and fast movers on the bottom. Workers can pick items from pallets on the mezzanine, using warehouse management systems to track inventory locations. Once picked, pallets are moved to the floor level to assemble loads, ensuring the cold chain remains intact until the products are loaded onto trucks. This method offers significant advantages over traditional systems where picking occurs in ambient temperatures on loading docks, risking temperature breaches.”
He notes that although an early attempt in Durban 28 years ago didn’t succeed due to its heavy-duty concrete construction and high costs, modern designs are more efficient and cost-effective, making mezzanine picking systems a viable option for today’s cold storage facilities.
“In the UK, mezzanine floors are almost a standard feature in mobile racked cold storage. The ability to maximise storage while maintaining accessibility is crucial. One reason why companies are reluctant to adopt mezzanine case picking inside freezer stores is the challenge of ensuring that workers can operate comfortably in freezer conditions. Traditional methods, such as rotating staff between warm and cold areas, have proven inadequate. Prolonged exposure to extreme cold, even with breaks in warmer environments, is detrimental to health and productivity.
“To address this, Barpro is collaborating with Delf freezer wear, a company specialising in protective clothing. This innovative design enables workers to operate comfortably at -25°C for extended periods, up to two to three hours. With this increased comfort, workers can then be equipped with voice technology, significantly enhancing efficiency. Voice picking systems have shown to be extremely effective; for instance, an Australian cold store reported that their investment in voice picking paid off within six weeks due to increased productivity,” says Cunningham.
“For existing cold storage facilities looking to integrate mobile racking, retrofitting is a viable option. Contrary to common belief, it’s possible to retrofit mobile racking systems. Techniques include overlay slabs or cutting into floors to install rails, depending on the floor’s condition and insulation. Properly educating employees on the importance and function of heater mats, which prevent frost damage to the floor, is essential for maintaining the integrity of the storage environment.
“Future-proofing new cold storage facilities by installing rails for potential mobile racking systems is a prudent strategy. This approach was exemplified by a project in Namibia, where pre-installed rails ten years later allowed for the easy addition of mobile racking, doubling storage capacity and significantly reducing costs. The investment paid for itself in less than six months.”
In the fruit storage sector, Barpro has observed a shift towards mobile racking after years of reliance on fixed racking systems – typically because fruit stores are not freezer stores, and the product moves faster. “Fruit storage presents unique challenges, such as higher pallet weights and the need for more space around pallets to accommodate slight leaning.”
He notes that in Central and East Africa, traditional cold storage models are being replaced by more sophisticated, albeit expensive, solutions. However, the Kingspan Modularis system offers a cost-effective alternative: this freestanding cold store doesn’t require an external structure and can be equipped with rails for future mobile racking installation, providing an economical yet efficient solution for the region’s growing cold storage needs. “If you also future-proof it with mobile rails, it is a great saving.”
Additional innovations in mobile racking include specialised applications such as drum storage, meat hanging, and wine storage – markets which are currently under-served by mobile racking.
The latest advances in freezer design
“The biggest move in the market at the moment is with regard to the refrigerant and the need for HC gas to replace HFC. This poses a challenge for manufacturers of commercial units designed to operate in high ambient conditions (above 32°C) due to the physical size of the HC compressor needed to achieve this performance,” says Sebastian Hills, sales director: Staycold International, commenting on emerging technologies that are influencing the future of freezer design and functionality, and the latest advancements in freezer design.
Regarding technologies that Staycold is incorporating, he adds: “Staycold is working with our compressor partners to have a range of compressors developed that will allow us to make this move and still achieve our high ambient temperature performance (up to 40°C).”
Maintaining freezers can present several challenges, but addressing these issues effectively is key to ensuring optimal performance. “One common challenge is managing the condenser, which plays a crucial role in handling high ambient temperatures. Regular cleaning of the condenser is essential for the unit to function efficiently, and this task is straightforward. To assist with this, we’ve created easy-to-follow instructional videos available on our YouTube channel. Another significant concern is the temperature differential between the freezer’s interior and the outside environment, which can range from 30-40°C ambient temperatures to -20°C inside the unit, creating a 50-60°C temperature swing. To combat this, it’s important to regularly check and replace door gaskets, if necessary, as they help prevent external air from leaking into the cabinet,” says Hills.
Additionally, user-related issues such as overstocking or placing unfrozen items into the freezer can affect its performance. Addressing these practices with users can help mitigate their impact and maintain the freezer’s efficiency.
He believes that the role of freezers in the retail sector, especially in Africa, is poised for significant evolution in the coming years. The frozen food market has experienced substantial growth recently, with a global market value reaching USD193 billion in 2023. This growth trend is expected to continue, with a projected compound annual growth rate (CAGR) of 5.4% annually through 2030. As this market expands, freezers will play an increasingly crucial role in retail settings, accommodating the rising demand for frozen products and contributing to the sector’s development in Africa and beyond.
“The quality of insulation in freezers has a profound impact on both energy efficiency and temperature control. Given the significant temperature differential between the external environment and the products inside the freezer, effective insulation is crucial. Our freezers are equipped with EcoMate polyurethane foam, Low-E treated, heated glass doors, and robust build quality, all of which enhance insulation. This combination not only ensures the unit operates reliably and efficiently but also optimally showcases the products within, maintaining their quality and appeal,” adds Hills.
Hills adds that energy efficiency in display freezers also significantly improves with the use of EC fans, which contribute to lower electrical consumption and reduced heat load inside the unit.
In South Africa, the key regulation that freezers must comply with is the IEC 60335 standard, which focuses on electrical safety. “However, this regulation is typically enforced mainly for imported products, leaving a gap in defined requirements for locally manufactured units. As a result, self-regulation and due diligence are crucial for ensuring product safety and quality in the South African market. For our freezers, which are exported globally, we adhere to various international standards, including safety protocols set by IEC and performance criteria from ISO and other multinational guidelines. We believe that enhanced regulation and clearer guidance in the local market would help customers make more informed decisions when selecting products.
“To ensure our products meet the necessary standards, we undertake rigorous testing and compliance processes, despite the challenges posed by limited local facilities. Since South Africa lacks independent testing facilities for hydrocarbon units, we send our products to Europe for IEC certification and approval. This process, although costly, is crucial for ensuring that all our units, whether sold domestically or internationally, meet stringent safety and performance standards. Non-compliance with these standards could lead to significant consequences, including potential safety risks, legal issues, and damage to our reputation. Therefore, maintaining adherence to these regulations is a top priority for us,” he says.
Staycold is actively adapting to the rising demand for sustainable and energy-efficient freezer solutions by leveraging its established history in these areas. “Our commitment involves continuously integrating the latest technological advancements and innovations through our R&D department. By staying at the forefront of technology developments, we ensure that our designs and materials are optimised for both sustainability and efficiency. This approach allows us to provide our customers with world class solutions that not only meet their needs but also align with broader environmental goals.”
ISO accreditation is a strategic investment that empowers businesses to enhance their competitiveness, mitigate risks, and seize new market opportunities. By adhering to globally recognised standards, organisations can build trust, streamline operations, and achieve sustainable growth. While the initial outlay may seem substantial, the long-term returns in terms of efficiency, customer satisfaction, and regulatory compliance far exceed the costs.
In today’s increasingly globalised business landscape, standing out from the competition is essential. ISO accreditation acts as a powerful endorsement, signifying a company’s commitment to quality, efficiency, and adherence to international best practices. By obtaining ISO certification, businesses can better mitigate risk while demonstrating their credibility and reliability to customers, suppliers, and stakeholders alike.
In reality a cold store operation is primarily about logistics, handling, storing and distribution of product. Depending which camp you are in, that sequence will be where your focus should be. However, management sees it as a complex problem with every sector being important to getting synergy of the whole facility.
Being a refrigeration guy, I always thought that the cooling side of the operation was the most important. Until one day, when working on a plant issue, my anxious client asked me what was happening and when would he be back up and running. I went into a whole lecture about all the issues – only to have the bemused client repeat: “when will I have cold air?” All he wanted was cold air. I have never forgotten that as I think it was one of the most sobering moments of my career. It’s that old adage ‘you can’t see the wood for the trees’. Well, I had lost sight of the service we were supplying, getting caught up in the detail and not the objective. Those few words of my client have stayed with me my whole life.
Being a member of the Global Cold Chain Alliance has broadened our outlook and we now see the bigger picture and have looked at addressing the following essential services when it comes to assisting facilities to get the best out of their cold store operation.
Primarily it’s all about basic management of the cold store facility and understanding how it all works, operating costs and resource efficiencies. The actual business revolves around logistics and that is where most cold warehousing staff are specialised. Moving product in and out is a major operation which needs to be focused in-house. Maintaining and operating the refrigeration system can be outsourced to specialised contractors who can take the workload and responsibility away from the cold store, allowing the staff to focus their efforts on storing and handling product.
We believe that the function of refrigeration systems in a cold storage facility is to deliver cold air at the correct temperature – it is an essential commodity. There will be the need to have an on-the-ground plant operator monitoring the day-to-day operation to a strict predefined programme. Each cold store needs to decide if they wish to become refrigeration experts or to enter an arrangement with a contractor who will maintain the plant.
However, each cooling plant has its own peculiarities that need to be addressed and is required to comply with legal safety requirements on the OHS Act as follows:
SANS 10147 sites statutory legal compliance requirements: All refrigeration systems should have a certificate of compliance issued by the construction contractor
Refrigeration operation manual, a requirement of SANS 10147: Simple information on components and how they work to permit a semi-skilled SAQCC Gas Cat A Plant Operator to monitor and be a front-line person in the plant’s operation working in conjunction with the site’s refrigeration contractor
Maintenance and checks that need to be carried out: Statutory inspections and checklist for SAQCC Gas Cat A operational personnel compiled in a user-friendly format
Record keeping: Plantroom logbooks for record keeping on site which are monitored on a regular basis
A lot of that should already be in place – and if not it’s maybe time to look at the control and operation of your refrigeration plant and ensure your plant operators are suitably trained and have the information required to allow them to do their job.
But it doesn’t stop there. One of the issues that we come across is a lack of preparedness for any type of emergency response. It’s painfully obvious that clients seem to think that a trained SAQCC Gas plant operator will handle anything that goes wrong on the site. Not so. The OHS Act requires that each site has a SANS 1514 emergency plan. This should be a working document on how to respond to an emergency uniquely tailored to the particular site.
The emergency response training needs to be tailored to the specific site’s emergency response plan for the site’s five emergency response teams:
- Ammonia responders’ team
- Evacuation team
- First aid team
- Firefighting team, and
- Security team
All five of these teams are required by the OHS Act to undertake site incident training once a year to ensure that they know exactly how to co-ordinate their efforts and respond in an emergency situation.
As you can see running a cold store requires a dedicated team, suitably trained and knowledgeable in their respective fields.