Research on energy influence factors and operational optimization strategies of subway station HVAC systems: A case study of Suzhou

The subway average daily passengers in China has exceeded 80 million, with total energy consumption reaching 25 billion kWh in 2023, highlighting the critical importance of energy saving in subway stations. This study conducted on-site data collection at a subway station in Suzhou located in hot summer and cold winter climate zone in China in 2024, gathering data on outdoor meteorological parameters, indoor temperature and humidity, hourly passengers, and HVAC system energy consumption.

EnergyPlus and the SARIMA are used to build the subway station energy simulation model and passenger flow model, respectively. The accuracy of these models is validated against measured data. The influencing factors of HVAC system energy consumption and their impacts are identified and quantified by correlation analysis. Results indicate that passenger flow exhibits a distinct dual-peak periodic pattern and has a highly significant impact on HVAC system energy consumption.

Other influencing factors, in descending order of impact, include indoor air temperature, equipment power, humidity, ventilation volume, soil temperature, wind speed, and lighting power. The design capacity of the HVAC system is found approximately 30% larger than the actual demand according to real passenger flow. Optimizing the system design based on actual peak passenger data and dynamically operating the HVAC according to real-time passenger data can result in a 20% energy-saving rate. These findings provide valuable insights into the optimized design and energy-efficient operation of subway station HVAC systems.