Supermarkets are part of people's daily lives. In turn, the refrigeration systems of these places are what guarantee that the food is kept fresh and with optimal quality for human consumption. A detailed look at the equipment for this segment.By: Héctor Gómez Pérez
It occurs to me to compare a customer who arrives at a supermarket with a diner waiting for the dish he ordered at a restaurant he was recommended. The diner waits, looks at his watch, concentrates on the couple who dialogue at the next table. Let's imagine that you are waiting for one of your favorite dishes: a sirloin in red wine sauce. The waiter brings you your order, but I guarantee that our diner will not taste your food if your dish is not well presented, if there is no care in the combination of colors and creativity in the arrangement of food.
The same will happen with the customer who goes with his cart along the fruit and vegetable section of a supermarket: he will not crave to take a cauliflower or a lettuce if its appearance is not of freshness or of optimal quality, characteristics that guarantee an adequate cold process.
If we analyze the situation from the perspective of the owner of the supermarket, the refrigeration systems are the guarantors of the conservation of the product and those that prevent the loss of it. In the same way, these equipment carry a good part of the load of energy consumption and therefore economic within these industries. It's remarkable then its importance, isn't it?
Supermarkets today
This tour to talk about refrigeration systems in supermarkets will be undertaken with Richard Osma, general manager of Weston Ltda., a Colombian manufacturing company; Fernando Becerra, refrigeration manager of Danfoss and Jorge Sierra Belauzarán, director of engineering and development of Ojeda Refrigeración, from Mexico.
Today supermarkets are looking for comprehensive and automated solutions in which operating costs are reduced and the efficiency of equipment is increased; as commented by Richard Osma "this efficiency translates into the elimination of product loss and the reduction of cold losses in the equipment".
For Fernando Becerra, the current needs of supermarkets in terms of cold solutions are summarized in low energy consumption, high reliability in the equipment, constant temperatures, low noise level and good service.
Solutions for the segment
Now, let's go on to analyze the solutions offered by the companies of the invited representatives for refrigeration systems in supermarkets. Weston Ltda.. offers solutions with a centralized digital control that is responsible for monitoring each of the equipment in the system, "so that the production of cold is done at the right time," explained Osma. In the same way, the furniture they are manufacturing has extended evaporators that require less Btu/ hr per ft, the differential between the evaporation temperature and the product temperature is decreased, and the time and number of thaws are reduced. "All this results in smaller machine sizes to operate and therefore savings in operating costs," concluded the representative of Weston Ltda.
Danfoss, a company that develops control technologies that seek to save energy, currently bases its product line on suction and discharge pressure control, with dead zone management or speed variation; electronic evaporation pressure regulation and electronic pressure valves, among others.
For its part, Ojeda Refrigeración has a variety of self-contained equipment that, as explained by Jorge Sierra, does not require special electrical installation (they operate at 127 volts / 60 Hz) or hydraulic of many requirements. In addition to freezers and bottle coolers, they have open showcases and air curtain equipment specially designed for supermarkets. "By design they are very energy saving and even exceed the consumption requirements established by the California Department of Energy," Sierra said. In addition to the above, the polyurethane insulation and refrigerants used by the equipment are environmentally friendly in accordance with the commitments to the Montreal Protocol.
Energy saving
We had already talked about this equipment assuming a large part of the energy consumption in a supermarket, but what are manufacturers doing to make them more efficient? Starting with Danfoss we have that its latest developments allow refrigeration systems to obtain savings of up to 30% with returns on investment of less than two years.
Here are some examples:
- Variable speed drives for compressors in parallel: they completely eliminate the peaks generated by the on/off control of these equipment, being able to even handle low partial loads with a constant suction pressure. The savings can reach 20% compared to a system without a drive.
- Electronic expansion valves: with high response speed and handling of low partial loads. Savings between 10 and 15% are obtained with respect to thermostatic expansion valves.
- MLZ Scroll Compressors for refrigeration: with savings of 20% on a hermetic piston. Its low noise level stands out.
In its refrigeration systems for supermarkets Weston Ltda. has been using more efficient elements such as LEDs, high efficiency motor fans, expansion valves and digital EPR valves controlled by servo motors, extended evaporators to increase evaporation temperatures, without affecting the temperature in the product. The type of refrigerant that they have been using also stands out in this equipment: R507a, R404a and R134a.
The successful system
A refrigeration system for supermarkets is guaranteed commercial success, as Richard Osma commented, if it favors customer expectations and guarantees the return on investment within a reasonable and attractive timeframe. In that same sense, Fernando Becerra expressed himself when he said that the equipment for these businesses has a good market penetration if they comply with an optimal maintenance of the humidity and temperature of the product, in addition to having a low energy consumption.
"The reliability of the refrigeration system is very important and is worth much less in investment than the possible losses of product or quality of the same in case of failures," Becerra said about the importance of this equipment in supermarkets. For Osma, its importance lies in the fact that "due to its appearance and technical characteristics, these equipment favor an increase in sales volumes and a reduction in energy consumption."
What we said at the beginning: the quality of a product or a food enters through the eyes and its presentation. Thus we end this tour in which several important points about refrigeration systems for supermarkets were touched, but we will leave on the inkwell a question that Fernando Becerra, director of refrigeration of Danfoss, asks users (the owners of supermarkets): "What investment criteria do users have? Are they willing not to be short-termists and think that the business becomes more profitable by investing in good cooling systems?" Definitely knowing how to handle this objection will become a very good sales strategy.
