When choosing equipment for a retail outlet, entrepreneurs often focus on dimensions and design, forgetting about the technical characteristics. Power of a display refrigerator - this is a critical parameter on which not only the amount of electricity bills depends, but also the very possibility of connecting the point to the power grid. An error in calculations can lead to constant knocking out of plugs or, worse, to damage to the wiring.
Energy consumption is directly related to how much heat the unit is able to remove from the working chamber. The larger the volume of the display case and the lower the required temperature, the more intense the compressor must work. In this article, we will analyze in detail what kilowatts depend on, how to calculate them correctly, and why the figures stated by the manufacturer may differ from the real ones.
Understanding these nuances will allow you to avoid overpayments and choose a model that will ideally fit into the infrastructure of your store. You should not rely only on the assurances of sales consultants; it is better to check the technical passport data once.
What determines electricity consumption
The main consumer of energy in any refrigeration equipment is the compressor. It is this that compresses the refrigerant, causing it to circulate through the system of tubes and take heat from the internal space. Energy consumption directly depends on the operating time of the motor: the more often and longer it turns on, the more kilowatt-hours the meter will accumulate.
There is a direct relationship between the ambient temperature and load on the unit. If the display case is in a hot room or in direct sunlight, the compressor has to work almost without interruption. In such conditions, even a model with a low declared consumption will “eat” electricity in buckets.
⚠️ Attention: Installing the display case close to the wall or in a niche without gaps for ventilation leads to overheating of the condenser. This can increase energy consumption by up to 30% and shorten the life of the compressor.
Consumption is also affected by the frequency of door openings or the presence of an open display. Every time the buyer picks up the goods, warm air gets inside, which the system has to cool again. Static models with doors are more economical, but dynamic open slides require significantly more power to create an air curtain.
Average power ratings for different types of showcases
The range of power consumption varies depending on the type of equipment. Small tabletop beverage models consume minimal energy, while large food islands can be a heavy load on the grid. Below is a table with average data that will help you navigate the numbers.
| Showcase type | Volume, liters | Average power, W | Consumption per day, kW*h |
|---|---|---|---|
| Tabletop (mini) | 50 - 100 | 80 - 150 | 0.8 - 1.2 |
| Vertical (door) | 200 - 400 | 200 - 350 | 2.0 - 3.5 |
| Horizontal (chest) | 300 - 500 | 150 - 250 | 1.5 - 2.5 |
| Open slide | 400 - 800 | 600 - 1200 | 6.0 - 12.0 |
| Confectionery display case | 100 - 200 | 300 - 500 | 3.0 - 5.0 |
As can be seen from the table, outdoor slides are the most energy-intensive. This is explained by the need for constant operation of fans to create an air curtain that does not allow cold air to escape outside. Confectionery display cases they often consume more than conventional refrigerators due to a powerful ventilation system and sometimes built-in lighting that simulates daylight.
It is worth considering that the indicated values are average. The actual figure depends on the specific model, year of manufacture and energy efficiency class. Old Soviet or early post-Soviet models can consume 40-50% more than modern analogues with inverter compressors.
The impact of energy efficiency class on costs
Modern equipment is marked with classes from A to G (in the new system) or from A+++ to D (in the old system). The difference in consumption between class A and class C may seem insignificant at first glance, but in terms of a year of continuous operation it results in significant amounts.
Equipment of a high efficiency class uses more advanced compressors, improved thermal insulation of the housing and energy-efficient LED lamps. Modern LED lighting consumes 5-7 times less energy than old fluorescent lamps, while providing better light.
When purchasing used equipment or models from previous years, you should be especially careful. The cheapness of such equipment is often illusory, since in 2-3 years of operation it will “eat up” its cost due to differences in electricity bills. Investments in a quality unit pay off faster than it seems.
Calculation of starting currents and load on the network
Few people think about this, but at the moment of starting the compressor consumes a current that is 3-5 times higher than its rated power. This is called starting current. If you plan to connect several display cases to one outlet or through an extension cord, this factor becomes critical.
For example, if the nameplate indicates 200 W, this means normal operation. But in the second of startup, consumption can jump to 1000 W or more. Weak wiring in old shopping pavilions may not withstand the simultaneous switching on of several units after a power outage.
For a correct calculation, it is necessary to sum up the rated power of all devices and add a margin of 20-30% for starting loads. It is also important to consider the cable cross-section. Powerful horizontal freezers or islands often require a separate wiring line.
☑️ Checking the electrical network before installation
How to reduce the energy consumption of a display case
There are a number of practical measures to optimize the operation of equipment without losing the quality of food storage. First of all, this is regular maintenance. A condenser clogged with dust (radiator at the back or below) impairs heat transfer, causing the compressor to work longer.
The second important point is correct loading. Do not block the ventilation holes inside the chamber with food. Air circulation must be free. If the product is “hilled up” to the very top, the cold is not distributed evenly, and the temperature sensor does not allow the compressor to turn off.
⚠️ Attention: Never place hot or warm products in the display case. Heating the chamber to 20-25 degrees will force the unit to work at its limit for several hours, which will sharply increase consumption.
The third aspect is the temperature regime. You should not set the minimum possible temperature if it is not necessary. For many products +4...+6°C is sufficient. A decrease in temperature by 1 degree increases energy consumption by about 5-6%.
Common mistakes when choosing power
One of the main mistakes is choosing equipment “back to back”. If the display case operates at the limit of its capabilities, it will quickly fail. Always choose a model with a reserve in volume and cooling power, especially if you plan to open the doors frequently.
The second mistake is ignoring the climate class. Equipment designed for moderate climates (SN, N) will work poorly and “eat” a lot in a hot workshop or summer cafe without air conditioning. For such conditions, tropical class models (T, ST) are needed.
The third mistake is the use of household extension cords for industrial equipment. Thin wires of household extension cords have high resistance and can melt under the load of a powerful compressor, especially at the time of start-up.
Why can a new refrigerator consume more than an old one?
New models often have more powerful compressors for faster ramp-up, but they shut down faster. However, if the new model is larger in volume or has a No Frost function, its overall consumption may be higher than that of a small old chest. Always compare kWh in the passport, and not by hearing the operation of the motor.
FAQ: Frequently asked questions
How many kW per month does one display case consume?
Depending on the type, consumption varies from 25 to 150 kW per month. Small tabletop models consume about 25-40 kW, standard vertical ones - 60-90 kW, and large open slides can “wind up” up to 150 kW or more during intensive use.
Does the occupancy of a display case affect electricity consumption?
Yes, it does, but not in the way that is commonly thought. An empty display case cools faster, but it is less inert. When the door is opened from an empty chamber, cold air quickly evaporates and is replaced by warm air. A display case filled with products (especially if the products are also chilled) maintains the temperature better, acting as a cold accumulator, which can reduce the number of times the compressor starts.
Do you need to turn off the display case at night?
It is strictly not recommended. Display refrigerators are not designed for deep defrost and refreeze cycles. This will lead to food spoilage, condensation formation inside the system and accelerated wear of the compressor. The equipment must work 24/7.
Is it true that glass doors increase consumption?
On the contrary. Showcases with transparent doors (even if they open) are much more economical than open slides. The door creates a barrier to heat exchange. An open slide loses up to 70% of the cold through the air curtain, while a closed volume retains the temperature much more effectively.