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Many areas around the world are struggling with water shortages. Numerous efforts to desalinate water and such businesses are evidence of the importance of this problem. The World Bank has estimated the number of people suffering from water shortages at 2 billion, which could rise to 4.6 billion over the next 65 years.
The connection between water and energy has become a constant issue in recent years. Power plants, which supply electricity to most countries, consume a lot of water, both directly and indirectly. When it comes to the readability of the cooling device, the discussion about water consumption does not seem very important. Which one to choose between cold water or cold air chillers depends on the result of this study.
What is a chiller?
The chiller takes the heat from once and transfers it to the surroundings with the help of a cooling system. This heat exchanger is a machine that is preferred in power plants and other large and detailed installations. It can simply be considered a system consisting of a water tank or a combination of ethylene and water and a cycle between components. In this way, the cooling fluid is rotated from the tank to the equipment that intends to cool.
There are also cool air chillers in which heat is dissipated by built-in fans. This type has recently become common in power plants. In this article, we will discuss the differences between the two chiller technologies and leave the choice between the two to you.
Cool water chillers
Cool water chillers have a cooling tower, so they are more efficient than air-cooled chillers. Coldwater chillers are more efficient because they compress depending on the ambient bubble temperature, which is lower than the dry bubble temperature. The less compact the chiller, the more efficient it is. This system has several essential components that include:
- cooling towers
- Water condenser pumps
- Water supply pumps
- Chillers
- TES tanks
What are the benefits of a cold water chiller?
Some people prefer these chillers because they are smaller and take up less space than cool air chillers. These chillers are also more efficient and last longer than other options available. For those who want to place the equipment indoors, the option of cold water chillers will be a better choice.
What happens in the evaporator?
The role of the evaporator is to produce cooled and cold water. This device raises the water temperature to 6 degrees Celsius (42.8 degrees Fahrenheit) and then directs it to other parts with the help of pumps.
A network of pipes delivers chilled water to any part of the building that needs it. After the exchange of cold with room air, which enters the room through air distribution units or fan coils, the water heats up to a temperature of about 12 degrees Celsius (53.6 degrees Fahrenheit). The water then returns to the evaporator, where the refrigerant absorbs excess heat to cool the facility. Remember that this water is called chilled or chilled water, no matter what the temperature.
What happens inside the condenser?
A refrigerant brings unwanted and excess heat from the evaporator to the condenser. There is another cycle that ends at the condenser and that is the water cycle between the condenser and the cooling tower.
After water enters the condenser at a temperature of about 27 degrees Celsius (80.6 degrees Fahrenheit), water at a temperature of 32 degrees Celsius (89.6 degrees Fahrenheit) leaves the condenser and moves to the cooling tower. Note that at no time are the refrigerant and condenser directly in contact with each other, and the heat exchange takes place only through the pipe wall. Condenser water with additional unwanted heat goes to the cooling tower to dissipate the next heat.
What’s going on inside the cooling tower?
This is where the unwanted excess heat comes into its own. A large fan gives air to this part. This air collides with the water coming from the condenser to this part. Through this direct collision, the water coming from the condenser releases its heat into the air and the water returns to the condenser to continue its cycle. The cooling tower, for which there is no roof and is open, is designed in different shapes depending on various factors. For example, types of cross currents, opposite and uneven currents, natural suction and mechanical suction are among these. This is a good way to resolve ambiguities about different types of chillers and cooling towers.
Cool air chillers
Cool air chillers are installed when there are aesthetic or environmental conditions or even limited access to water. Coldwater and air-cooled chillers both depend on airflow as a medium for heat transfer. The difference is that cold water chillers, or arguably their cooling towers, use humid airflow (ambient airflow + water spray), while cool air chillers use the air in the environment.
Coldwater chillers are usually cheaper and more efficient, but their high water consumption is a downside. Of course, there are ways to combine modern manufacturing methods and advanced technology to maximize air-cooled chillers. In this way, there are chillers that can compete with cold water chillers in various ways. For example in the amount of space occupied or the production of noise pollution.
Unfortunately, some people still believe that cool air chillers can not work well. In this case, all these people need to know is the performance of these chillers in the last two decades, whose NPLV rates have gradually increased over the years. The following are some of the benefits of using cool air chillers:
- No need for cooling towers
- Environmental compatibility and not wasting water
- Low maintenance costs
- Easier operation and control due to the lack of intermediaries such as towers
- Avoid chemical costs
- Avoid water costs, especially in cities
- No need to deal with water-related problems.
How to choose between these two types of chillers?
Cooling capacity is the main guide for choosing a chiller. Equally important is the balance between operating costs and budget. Although a value-based option takes into account both initial and operating costs, some customers base their purchasing decision on initial costs. Consider the costs of contractors and equipment together to determine the initial costs of each option. Remember that for cold water chillers, you also need to add a cooling tower to the system. When it comes to the cost of the life of the device, you have to consider both the cost of purchase and the cost of operation.
When you evaluate both types of chillers in this way, you will be able to determine the total cost of each. One thing to keep in mind is that cold water chillers usually look more valuable if their initial costs and water costs are ignored. However, it is only after considering the subsequent costs that their true picture becomes clear.
Conclusion
Energy costs remain an important issue in any equipment and energy-saving measures are applied everywhere. While chillers directly affect energy consumption, there are other factors as well. While cold water chillers can perform better in terms of energy, in other respects such as installation cost, maintenance cost, number of devices and other aspects they can compete rigidly with cold air chillers.
Most importantly, cool air chillers do not consume water, so they are an ideal alternative for areas with water shortages or areas where energy is cheap but water is expensive.
Source: araner.com
