How to choose efficient commercial refrigeration equipment?
Commercial refrigeration equipment is the largest and most expensive item in non-commercial retail purchases. The criteria for its selection are of great importance. Until a few years ago, retailers mostly purchased from the supplier that offered the best price and could supply a wide range of products. However, this approach does not verify the quality of the equipment supplied, resulting in loss of sales due to frequent breakdowns and lack of the required temperature, as well as increased operating costs due to low energy efficiency. In this article, the technical director of «Land» company Sergey Pleshanov explains how foreign retailers buy refrigeration equipment and what approach allows the retailer to choose the most efficient and profitable solutions in the long term.
The cost of energy resources in Russia is constantly rising and the purchasing power of the population has been declining for many years. Against this background, there is an obvious trend in shop construction - retailers aim to increase the energy efficiency of equipment and reduce operating costs.
Large federal networks have started to introduce TCO (Total cost ownership, or total (full) cost ownership) into the selection procedure for the supplier of refrigeration equipment. In this case, the selection of the supplier is based on a comparison of the price of the equipment with the cost of the resources used to operate it, which allows an objective comparison of the capital costs of the company and an accurate forecast of the operating budget and its use.
However, when directly comparing the data supplied by the suppliers, another problem arises: the installed capacity does not allow for a correct assessment of the efficiency of the equipment in operation because it does not reflect the actual electricity consumption.
There is no State-level procedure for verifying passport data in Russia, nor are there any voluntary associations or organizations where suppliers could evaluate their equipment on a voluntary basis.
If we look at household appliances, most of them - from a light bulb to a refrigerator - have labels (labels) with energy efficiency class. In addition to the energy efficiency class, the label shall indicate the main characteristics of the equipment to be marked.
The world has now standardized labels for evaluating the energy efficiency of electrical energy consuming equipment. Use efficiency is defined by classes - from A to G. Class A has the best energy efficiency, and G is the least energy efficient. A look at the markings suffices to evaluate the estimated costs of operating the equipment. Therefore, the EU Energy Commission has formed a logical requirement for energy labelling of commercial refrigeration equipment.
The following types of refrigeration equipment are subject to this requirement:
- with external cooling supply;
- with a built-in aggregator;
- medium- and low-temperature cooling chests;
- cupboards for drinks.
The label indicates:
- energy consumption,
- layout area for medium-temperature and low-temperature equipment;
- temperature classes for medium-temperature (M1 -1...5°C or M2 -1...7°C) and low-temperature (-15...-18°C) equipment.
The energy efficiency policy is aimed at stimulating the production and sales of more efficient products that consume less energy and, consequently, have less negative impact on the environment.
How to calculate the cost of operating a refrigerator?
Let's figure out how the equipment efficiency class is determined. Table 1 shows the correspondence of the energy class to the calculated index ЕЕI (energy efficiency index).
AE is the estimated annual consumption of a sample based on the results of testing equipment according to the international standard ISO 23953* (ISO 23953-2:2015 - Display cases-refrigerators. Part 2. Classification, requirements and test conditions), which includes data on the actual recorded consumption of the showcase and its cold demand.
SAE is the standard consumption per year calculated on the basis of the total display area obtained as a result of testing equipment according to the international standard ISO 23953 and tables with correction coefficients according to the temperature class of the equipment.
In other words, the calculated value reflects the real energy needs of the equipment and gives an objective value of consumption during operation.
Let's take an example of the evaluation of equipment by TCO. For the calculation, let's take a store with thirty wall-mounted outdoor cold display cases and one refrigerating machine corresponding to the capacity to provide slides with cold in medium-temperature mode.
The calculation of TCO is made according to the formula: ТСО = СAPЕХ + ОРЕХ,
where СAPЕХ is the capital cost of the total number of units of equipment;
ОРЕХ – operating costs for 7 years (for the calculation of operating costs, a period of 7 years is taken – as the average service life of the store's equipment).
Capital expenditures are calculated using the following formula:
CAPЕХ = CAPeq * К + CAPagg,
where CAPeq – the cost of one unit of refrigeration furniture equipment;
К – number of pieces of equipment;
CAPagg – the cost of an aggregator.
Operating costs are calculated using the formula: OPЕХ = ((Qcop*24)+(Ep*К))*365*N*C,
where OPЕХ – operating costs for refrigerated storefronts for 7 years** ownership;
Qcop – the average hourly consumption of aggregator based on the COP calculated on the basis of the formula:
СОР = (Q1/СОР)*К+QF),
where Q1 – the average hourly value of the cold consumption of the merchandising refregerator (taking into account defrost);
СОР – average refrigeration coefficient depending on the compressor model and type of refrigerant;
К – number of pieces of equipment;
QF – consumption of condenser fans, kW;
Ер – the energy consumption of the showcase, kW/day.
К – number of pieces of equipment;
365 – number of days per year;
N – number of years of operation;
С – the cost of 1 kW of electricity.
Manufacturer X offers a wall-mounted display case with a cold demand of 3 kW, manufacturer Y offers a wall-mounted display case with a cold demand of 1 kW. Let's assume that the energy consumption of storefronts (heating elements, lighting, fans) is the same and amounts to 2.5 kW, since this parameter makes a negligible contribution to the structure of the energy consumption of the store.
As a result, it turns out that over the 7 years of the store's operation, the difference in the cost of electricity consumed by equipment from suppliers X and Y will amount to more than 1.5 million rubles (see Table 2) - due to the noticeable difference between the workload of the refrigerator, which is the main consumer of electricity in the context of cold supply.
With a decrease in the cold demand of commercial equipment, the required cooling capacity of the refrigerating machine is correspondingly reduced, and hence capital costs.
Thus, even with a noticeable difference of 15-20% in the cost of equipment (CAPEX) from supplier X (which, if all things are equal, is possible only by reducing the quality characteristics of the equipment) supplier Y will have a more interesting offer when calculating the total cost of ownership, taking into account the technical characteristics that ensure the savings of OPEX within the 7-year operation of the store.
Compliance with the temperature regime
Along with energy efficiency, one of the key tasks of testing is to obtain data on the temperature field in the cooled volume. If the supplier specifies the temperature class M1, this means that at any point in the volume the temperature of the product should not fall below -1 ° C and rise above +5 °C. Compliance with the temperature regime is the most important parameter of refrigeration equipment, which determines the quality of the stored product. In case of non-compliance with the temperature class, such equipment, as well as its supplier, should not be allowed to participate in the auction.here are no labeling requirements in Russia, but there are already requirements for testing refrigeration equipment that fully comply with ISO 23953 - ГОСТ 32560.2.
Equipment testing
Recently, professional laboratories have begun to appear in Russia, which conduct tests in accordance with the requirements of ГОСТ 32560.2 and allow verifying passport data, as well as giving a real analysis of the energy efficiency of the supplied equipment.Among them, there are several laboratories operating in strict accordance with ГОСТ. Thus, the laboratories "Arneg", "Brandford" and "Spectr" offer a full range of services for testing commercial refrigeration equipment in full compliance with the requirements of ГОСТ 32560.2. According to ГОСТ, tests are carried out in a climate chamber equipped with high-tech automation devices and equipment for maintaining the climate and simulating various operating conditions corresponding to different climatic classes. Information from all devices of the tested equipment, starting from the temperature at 54 points inside the product simulators and the cooled volume, relative humidity and air flow velocity in the room and ending with the flow meter of the refrigerating agent for accurate calculation of cold demand, is synchronized in time, archived and reduced to the dispatching unit.In addition to testing for compliance with cold and energy consumption data, laboratories conduct a full analysis of equipment compliance with the requirements of the technical specification, the load capacity of the equipment and the absence of the possibility of condensation. According to the test results, a detailed protocol is issued.
Abroad, companies comprehensively approach control at all stages of the life cycle - from design and selection of equipment to installation and maintenance. Thus, control is carried out throughout the entire cycle of equipment operation, which makes it possible to achieve in practice the calculated TCO figures. So, in Europe, the Swiss company "Frigoconsulting" performs audit services for facilities. It is gratifying to note that there is a demand for such services in Russia and relevant experts have appeared. For example, the specialists of the company "Spectr" LLC provide a full range of technical audit services for commercial and industrial refrigeration facilities, provide the customer with an independent assessment of the compliance of the installed equipment with the technical specifications and stated requirements, as well as audit the quality of service work of refrigeration equipment.
Holding tenders on the basis of TCO allows leading federal networks to evaluate equipment not only by the price of exploitation, but also by the quality of maintaining the temperature regime, which is certainly a big step towards the energy development of commercial refrigeration equipment And the introduction of energy labeling in Russia is a matter of the near future, since it has already become an urgent necessity. The presence of testing laboratories on the territory of the country will allow the assessment to be carried out in full today.