Battle against the global warming
The amount of energy required to maintain conditional temperatures in refrigerated cabinets should be decreased both at the start point, reducing the fixed energy consumption, and in operation.
Reducing the fixed power depends directly on the capacity of compressors, which are selected for special climatic conditions and are calculated together with air condenser for the hottest summer periods.
Thus, we determine the task: both compressor and condenser should be made smaller and cheaper, which is possible if the air temperature is lower. However, during last years in the regions, where it had never been hot, summer weather conditions became like in sultry deserts, while in deserts it snowed.
This is why clients set the air temperature up to +40/+43°С in their last years technical specifications when choosing the condenser. Therefore, the price of equipment and its setup capacity increase.
How to solve these problems?
Using evaporative cooling (water cooling tower), we managed to maintain the injection pressure of cooling unit compressor at the level of condensing temperature +40/+43°С through water evaporation and use of water condenser. Rise of air temperature up to +45/+50°С will not have a dramatic influence on the operation of cooling tower as the high-quality operation is ensured not by temperature, but by humidity.
The use of water cooling towers is not an innovation. However, they were not used in retail trade as it is very difficult to provide antifreeze conditions to water during the winter period in our latitude.
«Aisberg» has been working on the joint operation project for water and air condensers for several years, subject to safe maintenance in combined mode, both in summer and in winter. We have carried out several tests. During the operation of test water cooling towers in working stores in Ukraine we have confirmed the results of theoretical calculations.
The use of combined operation system of both water and air condensers has the range of advantages:
- decrease of the set power of multi-compressor unit by 30-35%;
- downsizing of air condenser in 2-3 times;
- if the sales area is from 1,500 to 2,000 sq.m., the price of traditional cooling system and the combined cooling system (including water cooling tower, pumps, water condenser) is the same. With extension of sales area, the use of combined cooling system becomes more efficient;
- power consumption in maintenance mode of the cooling system at environment temperature +10°С and more is decreased by 15% on average
- the source of compressor operation increases twice because of the working pressure fall from emergent to normal;
- the problem of starting-up the store cooling system from defrosted state in case of short-term power cut in a store in summer is solved completely.