We live in a world of immediate answers, Google, Wikipedia, which leads us naturally to an understanding of instant solutions. We want answers quick! and results quick! That’s just how things are these days, and that’s fine, but in dealing with some problems we need a more measured approach, a more systematic approach with a broad view. Leaking supermarket display chillers is one of these problems.
Biofilm jelly in retail refrigeration is one problem, but the correct diagnostic, and cost impact understanding of this problem is completely different. So in order to view the full context, we need to start at the beginning, and where better to start than the Carbon Trust Roadmap for Refrigeration produced in association with the Institute of Refrigeration. (IOR)
“In the UK, refrigerated display cabinets use around 5,800 GWh/year. This is over a third of all the electricity used for refrigeration in the food chain and costs around £500m per year…
Refrigerated display cases rank number 1 in areas where energy use can be significantly cut.”
The Carbon Trust has identified cleaning and maintenance as the largest area for a reduction in energy consumption food chain refrigeration. This dwarfs all other areas identified for energy reduction, “night covers” achieve 1%, “night blinds” 4%, “LED lighting” 7%, “transparent doors” 8% whereas “cleaning and maintenance” realises a 20% margin for energy savings.
If we consider this 20%, we need to take a quick glance at supermarket refrigeration maintenance and breakdowns. How many call outs to the chillers are for water leaks? It can vary between one in three, and one in 15, sufficient to say, it does account for a lot of call-outs. The next question for us would be, how many of the water leak call outs are caused by biofilm jelly blockages? well, we can answer this by reversing polarity. We take a sample store with a history of bad water leak call outs, we check the drains aren’t blocked below ground, then install one Gel-clear tablet per case. The rest is simple, we see month by month that the water leak call-outs have dropped by over 98%. This would suggest most of the water leak call-outs were attributable to biofilm jelly blockages.
So to accurately measure what proportion of the 20% we can recover here could only be best guessed, but we can view the full system and see the other costs saved in that reduction. On the store we installed the tablets, one of many customer trials we do, the branch had been spending approx £2400.00 a year for the previous three years on absorbent strips to manage water leaks…….reduce that by 98%. Then we have 47 call-outs that didn’t happen over the 9 month trial period at £140.00 per attendance…..that’s another £6580.00. We have reduced slips, trips and falls claims……..pro-rata, this is before we touch on the savings in staff time managing the water leaks, loss of case revenues, and energy savings. The cost to treat the store with tablets? about £500.00. less than 3 pence per case, per day.
Imagine how efficient our refrigeration would be if refrigeration engineers could spend more time doing their jobs than dealing with drains? Because unfortunately, the biofilm jelly affects the overground 40mm case plumbing, not the below-ground 100mm drains.
It is only when we view the full system, we can see the full cost impact, only then can we see that prevention is the only cure. The problem of biofilm affects many industries, and many industries have successfully resolved the problem, usually driven by costs. Solving the problem is context-specific, each industry has to deal with it in their own context, refrigeration is no different, but it is important first to understand the problem!
One of the worlds leading researchers on biofilms and biofouling quoted over 20 years ago a very relevant quote that still applies today…
“The effects of biofouling on plant performance, water quality, and the equipment are frequently enhanced because they are not recognized in time, underestimated and linked with wrong causes. Thus, they require expensive and difficult countermeasures, which could have been avoided if the problem would have been recognized earlier. That is why awareness is a “preventive tool” in biofouling and biocorrosion .” H. C. Fleming.
A combined effort in the effective treatment of biofouling in supermarket refrigeration must incorporate a full system philosophy, taking a broad view of cleaning, operations, maintenance, and PPM in order to understand the impact and resolve it effectively.