On the first day of 2015 the system of tariff flags became effective, which added an extra charge over the electrical energy tariff. The action was adopted due to an increase of the use of thermoelectric plants, since the hydroelectric plants have low water levels in the reservoirs. This way, the expectation for 2015 is a significant increase in the tariffs that goes beyond the adjustments of the last years. ABRAS has informed that the cost of energy represents about 1.5% of the supermarket turnover and may increase up to 1.7% in 2015.
The refrigeration systems are accounted for the majority of the energy consumption in the retail system and, thus, the automation has been one of the adopted solutions to reduce the consumption in the short term. Lucas Riga, mechanical engineer and consultant for refrigeration projects in supermarkets all over the country, reminds us that the investment of this sector in energy efficiency began with the adoption of electronic components of control. Afterwards the networks started using frequency converters to control the rotation of the compressors, as well as electronic expansion valves and electronic controllers of the refrigeration systems.
Marcellus Cerchiai, engineering manager of Walmart Brazil, stated that the network expects to reduce at least 12% of the energy consumption per square meter until 2020 with the revision of the whole refrigeration system and the implementation of new air conditioning devices in the stores.
Another action that has been adopted in the retail sector in order to save electrical energy was the implementation of doors in the counters, not only in the islands of frozen foods, but also for the counters of cooled products, dairy products, meats and even fruits and vegetables. "Without doors these areas are responsible for the consumption of over 40% of the energy total of the store", added Cerchiai. In order to reduce the consumption and to guarantee a more efficient use, Walmart Brazil intends to install doors with LED lighting in the refrigerators, which will represent a great economy in energy. "By closing the refrigerated counters, we have already reduced the store's energy consumption around 8%". Besides, Walmart Brazil has adopted compressors with capacity control, electronic expansion valves and electronic engines.
Carrefour has also reduced the electrical energy consumption by investing in preventive maintenance and by using correctly the air conditioning and refrigeration systems. This initiative alone has already been responsible for reducing the total consumption of energy of the company by approximately 2%, between January and November of 2014. Still in 2014, an Internal Commission of Energy Conservation was founded to raise the awareness of the teams of all of the units of the network regarding the rational use of electrical energy.
Another example is Coop which revitalized its unit in Diadema. The renovation, which includes both retrofit and the amplification of the sales area, considered the areas of cold rooms and the preparation of perishables as a priority, expanded by 300 m², to receive modern refrigeration equipment, transport and conservation of the products. It is expected that the energy economy shall reach 12% through the introduction of a set of automation controllers of the refrigeration and air conditioning systems of the store, such as the refrigeration racks, the condensers, the cold rooms, the refrigerated counters and the preparation areas. Although some of the networks invest in automation, there is still a lot to be done. Riga explained that around 80% of the supermarkets, today, still have facilities that use up a lot of energy. "Many people build new stores and opt for more financially attractive solutions. This way, they end up using equipment and components that aren't as efficient. The greatest challenge is to convince the supermarket owners that new stores should count of efficient technologies, in addition to the importance of carrying out the retrofit of the existing stores."