With the rapid growth of computer network business and increase of servers, the size and scale of the computer room is also expanding. Moreover, the energy cost of data center is increased rapidly, with the trend of catching up the hardware cost. The authoritative investigation shows that China's annual total expenses for server power and cooling exceeds $ 2 billion.

As for the established data centers, you should consider how to achieve effective energy saving from many different aspects. This paper introduces several major solutions to energy saving of infrastructure in data center.

1、Design A Whole Computer room Monitoring System

Figure IT Equipment Load Curve

From the view of computer room load and air conditioning cooling configuration, the computer room is generally designed for the safe operation mode N+X. However, from the view of IT equipment layout in computer room, due to large computer room, take consideration of circulating air volume, reducing the local temperature dead ends problem of computer room and the dynamic changes of load equipment power consumption, precision air conditioning group cannot conduct artificially control in accordance with the needs of running. Heat changes in the computer room cannot follow, all indoor fans are running at full speed, and compressor is controlled by each air conditioning according to its own needs. This operating mode from the view of operating costs is not economical and efficient. If you force all the redundant equipments of air conditioning group shutdown, because the air-conditioned computer room airflow and temperature variation is difficult to grasp, the way of artificially control the startup and shutdown of air conditioning is difficult, so there may be uncontrollable phenomenon of local temperature. Therefore, the precision air conditioning group will play a crucial part in controlling the computer room energy saving.

The idea of dedicated air-conditioning group in the computer room controlling energy saving is: in terms of the computer room equipment working well, reduce the energy consumption of the entire computer room by reducing the running time of the redundant air conditioning equipment to achieve the air conditioning system backup/round robin function, cascading function, and avoid competition run, delay-start function.

Under the combination of Sugon group power and energy consumption monitoring system, conduct centralized management of precision air conditioning rows. According to CPU share, management software will calculate each row of server power consumption. On the basis of load distribution and precision air-conditioning distribution, precisely control the state of each air conditioning, including the start and stop of the compressor and the start and stop of the fans in air conditioner indoor unit. Precision air conditioning will communicate through RS485 network communication protocol, which works through the coordination of Ethernet and management node, so that the precision air conditioning (with monitoring function) from different manufacturers can exchange data information through the standard protocol interface and the management node data of Sugon. Each server cabinets installed two wireless temperature and humidity probes, each row of cabinets is set up a network, and form a temperature and humidity monitoring network through the internet of things networking and upload to the management nod through Ethernet data to form a two-layer monitoring network. When the server’s temperature is monitored to warm up, open computer room air conditioning to conduct energy saving and at the same time to ensure the safety of equipment.

2、Establish A Computer room Cooling and Airflow Models

The professional heat engineer will use computational fluid dynamics (CFD) technology for the numerical analysis and model experiments of the center computer room air, analysis fully the distribution of airflow velocity field and temperature within data center computer room, draw on reasonable design amount of cold deployment, and get the best wind back to the state to meet the cooling needs of the equipment. At the same time, the air conditioning load will reduce to get the good effect of optimal cold configuration. At present, it will be achieved by the main AIRPAK or FLUENT simulation software.

Figure Computer room CFD Airflow Simulation

3、Add a Blanking Plate For Cabinet

Due to the equipment quantities in part of the cabinet within the computer room is small, the cold air get up into the cabinet from the cabinet lower part, but a large part of the cold wind has directly entered the computer room other than passing through the equipment, which causes short-circuit of the air-conditioned air supply. Therefore, air-conditioning cooling efficiency is greatly reduced.

Closing air channel will reduce the short-circuiting of wind, and improve the efficiency of air conditioning refrigeration. The specific measure is to install the blind plate in the cabinet where there is no equipment, so that the cold air can only be sent to the computer room by the equipment.

Figure Increasing Blind Plate Airflow Organization in Cabinet

4、Installation Of Active Blowing Element-ADU for Cabinet

Air distribution of traditional floor is blowing inefficiently due to the distance of blowing is longer. Therefore, it will result in insufficient outlet cold requirement and wind volume and cannot meet the cooling requipment.

In such cases, it needs to install an initiative wind device-ADU at the outlet. ADU is equipped with two or four EC fans, and fan speed can be adjusted according to the load of cabinet. Through this initiative blowing device, you can improve the efficiency of air conditioning blowing. Then, it can meet the demands of cooling capacity and wind volume to reduce the number of units of air-conditioning and achieve energy saving.

Figure Increased Floor ADU Airflow Organization in Cabinet

Figure ADU Module Effect

5、Cold Aisle Closeness For Cabinet

Traditional under-floor air supply of air conditioning in the computer room is diffuse air supply. This supply way is likely to cause air short-circuit and insufficient air supply, resulting in low efficiency of air conditioning refrigeration.

Now we can use the way of cold aisle closeness to separate hot and cold airflow from each other to prevent air short-circuit and hot and cold wind mixing. It can greatly improve the efficiency of air conditioning refrigeration, and it is able to satisfy the normal computer room equipment heat requirement, even part of the air conditioning is off, then, you can achieve the energy-saving effect.

6、Adding New Air System In The Computer room

At present, many large data centers adopt new wind system to achieve energy-saving. Because the computer room is confined and the equipments discharge a great amount of heat, precision air conditioning needs 24 hours uninterrupted running in the whole year. Cooling and humidification take large power consumption. By the introduction of new wind and enthalpy control technology, in spring, autumn and winter, outdoor low-temperature air can be introduced, close precision air conditioning, at the same time under the premise of ensuring the temperature, humidity and the computer room cleanliness, achieving the purpose of energy saving.

7、Transform Precision Air Conditioning of the Computer room, so that it has a Natural Cooling Function-Using the Fluoride Pump Energy-Saving System

Traditional under-floor air supply air conditioning still requires refrigeration even when outdoor environment is lower in winter. It cannot take full advantage of the outdoor natural source of cold, result in poor energy-saving effect. From this situation, we can upgrade the air conditioning system, add fluorine pump units on the original air-conditioning system. Turn off the compressor through control system when external environment is low in winter, open the fluoride pump system for cooling because it consume less energy than the air-conditioning compressor. Take central data as an example, the air conditioning will save up to 20% of electricity consumption every year after improvement.

Sum up the several above energy-saving measures, according to local conditions of the old data center, identify problems, analyze the most appropriate solution, conduct maintenance through the monitoring of high intelligence and meticulous management to ensure high availability and high reliability and maximize energy optimization of the energy consumption of the data center computer room.