Cold Link Africa March/April 2019 | Page 35

FEATURE INCORPORATING COLD CHAIN An insider’s look at supermarket refrigeration in SA By Ilana Koegelenberg I Refrigeration solutions for the retail space are becoming more efficient and sustainable by the day — where are we going in terms of commercial supermarket refrigeration installations and what are some common mistakes made that can be avoided? recently had a chat to various key stakeholders to try and get a better understanding of the dos and don’ts of supermarket refrigeration (locally and beyond our borders). Engineers, contractors, manufacturers, and even end-users got involved to help paint this picture of an industry so vast, so progressive, that it is hard to keep up with. Once again, I was ill prepared for just how vast this topic is … If I had to pen an executive summary on this vast topic, it would be as follows: we are keeping up with technological advances and international trends, but not in terms of skills, and natural refrigerants are the belle of the ball for sure. Supermarkets are among the greatest commercial energy consumers, explains Roy Naidoo, area sales manager at Danfoss South Africa. For retailers, the energy expense is second only to labour when looking at operational expenses and typically accounts for over 3% of turnover in an increasingly competitive business where profit margins average below 2%. Refrigeration and heating together are the greatest energy consumers. “Although great savings have been achieved in recent years, much more is possible,” says Naidoo. REFRIGERATION MATTERS Supermarkets are becoming more efficient in terms of their refrigeration systems and energy usage. LOCAL TRENDS By fine-tuning the refrigeration system, great energy savings can be realised. Taken at PnP Northgate. The biggest trend seems to be a move towards more energy-efficient installations, as with most of the construction industry. This is achieved in many ways. Here are a few of the trends the stakeholders have noticed in the local arena … The refrigeration trends, certainly in supermarket refrigeration, have accepted the principle of centralised multiplex plants with electronic controls and monitoring, explains Merrick Smith, managing director of Pro Active Refrigeration. Larger stores on simplex-style solutions are not as common anymore. “This has been as result of factors such as energy efficiencies, costs, and the change in the nature of retail trade,” he explains. Certainly energy efficiency was a huge factor in consideration when the cost of power was rising at a seemingly uncontrollable rate from 2010 onwards, and energy-saving devices such as variable speed drives and electronic control systems were being retrofitted to existing systems and added as standard to new systems being installed. “Consumption levels of plants today are far more efficient than their predecessors a few decades ago and some credit must also be given to refrigerated cabinets becoming far more efficient in later years as well,” says Smith. “In fact, I believe that more and more retailers are going to introduce doors on upright display cabinets and sliding tops on island freezers, because the benefits of power saving are just too great to ignore.” As shoppers become more accustomed to this style of shopping culture and acceptance becomes commonplace, most retailers will accept doors on chillers the same way we moved from open upright freezers to glass door freezers over the past 20 years, he predicts. One of the most noticeable ‘trends’ is of course the change of refrigerants. Refrigerants began to change with the phase out of R22 and the norm is mostly R404A (with R507 being considered an alternative), R134A, and R744 (CO 2 ), says Smith. The use of COLD LINK AFRICA • March/April 2019 R404A as both a medium-temp and low-temp refrigerant is commonplace, more so than R134A and is possibly attributed to how many existing R22 plants were converted to R404A. This may be a factor in why even new plant specifications are often designed as R404A plants for medium temp as opposed to R134A. CO 2 is the talk of the town it seems and has been in use in supermarkets for a decade now. Many used a subcritical low-temp CO 2 system in conjunction with a R134a or R404A medium-temp system over recent years and have now made the change to both systems being CO 2 by having trans-critical plants installed, explains Smith. “With smaller retail groups also considering trans- critical systems, we may soon have the market split into those groups embracing CO 2 and those that don’t at all.” “We’ve noticed that CO 2 has definitely become one of the preferred refrigerants to use in supermarkets in South Africa,” says Maurice Robinson, director: sales and marketing at www.coldlinkafrica.co.za 35