Research On Energy Saving For The Telecommunication Base Station By Using Free Cooling

In the total energy consumption of telecommunication base station，the airconditioning energy consumption takes a large part. Using ambient energy to cooltelecommunication base station in the spring&autumn transitional seasons andwinter is an effective measure, which indicates that the potential of energy saving isconsiderable. Basing on the analysis of the energy consumption characteristics andenvironmental requirements, the theoretical model is set up, and the simulationanalysis about the telecommunication base station is carried out in the cities whichhave meteorological data of the software in China. The telecommunication basestation prototype with100mm sandwich panel building envelope is tested; thechanges of indoor and outdoor temperature, air conditioning cooling load with onlyair conditioning are analyzed. The energy consumption comparison between the freecooling and air conditioning are analyzed, and the energy saving rate of the threekinds of free cooling is also compared.Taking the brick wall with370mm thicknesses and the sandwich panel with50mm for example, The effect of air conditioning coupled with thermosyphon heatexchanger、glycol heat exchanger and fresh air heat exchanger on the energyconsumption of telecommunication base station is compared with that of airconditioning system, and get the distribution of the energy-saving effects in China;The influence of airflow organization in communication base station is discussed, andthe mathematics model is established to give suggestion for improving the air flow;the influences on the heat transfer efficiency of the thermosyphon heat exchange areanalyzed through the test results and the method to improve the efficiency is given.The results demonstrate that:Firstly, the air conditioning coupled with free cooling are used in differentenvelops with telecommunication base station, the results show that the89%cities inChina can use the thermosyphon heat exchanger,86%cities can use the glycol heatexchanger, and94%cities can be applied to the fresh air heat exchanger and the citiesenergy saving rate all above25%. The energy saving rate of the northwest in China ishigh, a top to64.5%, the investment recovery period is the shortest to0.9year; thefree cooling ways are not suitable for the southern districts because of low energy saving rate and long investment recovery period.Secondly, the major influences of the air distribution for the telecommunicationbase station are the heating value of indoor equipments, the layout of air conditionerand cabinet, the temperature&speed of the air conditioning, the height difference forair conditioning vents. The two air conditioners in the base station should be adoptingdiagonal distribution, be as close as possible to the heating equipments.Thirdly, according to the operating conditions of the telecommunication basestation, key factors which are relevant to the thermal performance of a thermosyphonheat exchanger include refrigerant，the tube arrangement,etc. The results show that:R32and R410A have better thermal performances; with the increase of wind speedand the reduction of tube numbers for windward, the heat transfer can be improved.Fourthly, the test results demonstrate that there is a small deviation between thetest results and theoretical analysis; the energy-saving effects can be to some certainextent reflected by the theoretical simulation.In the ways of free cooling, the best is the thermosyphon heat exchanger, theenergy-saving rate in the northwest and parts of southwest is great, and have no badeffects for the cleanness in the base station. It has great significance for reducingenergy consumption in the telecommunication base station.