How to reduce the energy cost of the Cooling system

Cooling system,In improving the energy efficiency of the data center, the IT load itself is the most important part of the consideration. The next is the load of the refrigeration system, which is the second major energy consumption part of the data center. Therefore, great efforts have been made to ensure the efficient operation of the refrigeration system.

The three basic steps to achieve high efficiency are the choice:
First: have the appropriate refrigeration system architecture;
Second: air flow management in IT space
Third: the use of effective refrigeration control system.
The above three steps need to be considered in the design stage, but in order to ensure the expected efficiency during the data center operation, the most important step is to ensure the design and operation of the control system is reasonable.
After all, the operation of the whole refrigeration system is quite complex. The overall operating temperature of the data center, as well as the temperature in a specific location, will fluctuate according to the multiple variables in the room. A temperature sensor is installed in a position to ensure the indoor temperature of different locations in the installation process of proper monitoring, in the operation and maintenance period to take appropriate control measures to effectively control the temperature, the processing can maintain the balance between the efficiency and the power load of the refrigeration.
It is worth noting that the most appropriate measures are often taken to deal with the problem of local temperature rise in the data center, and the effect will be obvious.
For example, for an air-cooled chiller design, there are two reasons for reducing the energy consumption of the unit if the IT temperature and the set value of the cooling water temperature rise. First, the data center can run most of the year by using a heat exchanger (economiser). Second, improve the energy efficiency of the unit.
If the air temperature of water-cooled air conditioning (CRAH) does not increase with the increase of chilled water temperature, it indicates that the cooling capacity of CRAH is decreasing, and the speed of CRAH fan needs to be improved. Of course, this will increase the energy consumption of CRAH. In addition, the energy consumption of the refrigerating unit will increase as the use of heat exchanger is extended.
Obviously, because so many systems depend on each other and interact with each other, if we do not monitor and manage all parts of the system accurately, we will not be able to tell whether the operation has increased efficiency. Maybe in the long run, it will have the opposite effect.
The effective control system is from the management level, the cooling system facilities as a whole, comprehensive consideration of the effect of its refrigeration. This, in turn, means that automatic control is needed to replace the effective control system of hand. We should switch between different operation modes according to the outdoor temperature change, such as manual, semi-automatic and automatic mode, so as to achieve the effect of reducing energy consumption. Effective control system should also include coordinating the operation of indoor refrigeration equipment. The humidity of data center should be centralized controlled through dew point temperature of IT vent, which is more cost-effective than controlling the relative humidity of air conditioner through control. Flexibility and easy maintenance are the key elements of a measured control system.
The best way to establish effective refrigeration control system is to manage equipment level, device level, group level, system level and control level (facility level).
Device level control involves the control of a single device (such as a chiller). This control is usually built in the equipment by the supplier itself. Device level control is usually not suitable for communication with other devices, but as the basis for a higher level control plan.
Group level control refers to the coordination of the same type of device, and the same type of device usually controls the same algorithm (because it is from a vendor). The limitation of control is that it can only control similar devices, and the equipment is usually only from the same supplier.
The system level control, the upper level of the group level, coordinates the operation of the refrigerating subsystems (such as the refrigerating pump and the CRAH) in the data center. However, this control system usually has a good effect on the same supplier's equipment. Therefore, it is necessary to consider the highest level control system for the overall control system of large data center: device level control.
The control level integrates all the functions of the refrigeration system into a common network, from heating equipment, ventilating equipment, air conditioning and lighting system to safety, emergency power supply and fire fighting system. It can intuitively see the operation of the entire air conditioning system through visual software, and achieve a unified and effective cooling strategy for data center impact.