Evolution characteristics of energy efficiency parameters of environmental control equipment in underground railway stations with operation years

Based on the stratified sampling test method and the Grubbs test method of removing bad values from the measured data, studies the environmental control equipment and systems of 18 stations with different operation years in Shanghai Metro. The analysis indicates that the COP of the water chiller is 3.78, 4.64 and 3.92 respectively in the initial-term, middle-term and long-term operation of the station, showing a trend of higher in the middle-term and lower in the initial-term and long-term. The average thermal performance parameter of the cooling tower and the EER index of the cold source system show a trend of larger in the middle-term and smaller in the initial-term and long-term. However, the power consumption per unit air volume of the cooling tower has little difference between the initial-term and middle-term, but it increases by 65.4% in the long-term relative to the initial-term. The efficiency of the cooling water pump and the chilled water pump fluctuates around 0.85, which has no obvious correlation with the service life.