Energy Consumption Evaluation and Energy-saving Potential Analysis of the HVAC System for an Office Building in China

According to the annual operation records of the HVAC system in a typical office building in Changsha city,energy consumption characteristics of the HVAC system are analyzed in this paper.Annual supposed air conditioning loads and its annual energy consumption are further calculated by ASHRAE's BIN(temperature frequency) method,and energy consumption performance of the HVAC system is estimated with the coefficient of energy consumption for air conditioning(CEC).Based on these studies,energy-saving potential of the HVAC system is analyzed from the three perspectives of air conditioning units,operations and management of the water system,and setting indoor air parameters.The conclusions are as follows:(1)In the annual energy consumption quantity of the HVAC system,the energy consumption of heat and cool resources amount is up to 54%;terminal units occupy 25% and the water systems contribute to 21%.(2) The CEC coefficient of this HVAC system is 2.0,larger than Japanese CEC benchmark of 1.5,which means the energy utilization efficiency of this HVAC system is low,and there is large energy-saving potential.(3) The energy consumption of this HVAC system can be reduced by adopting scientific operation schedules for heating and cooling resources and the water system.The case study shows that the total EER and rate power of this system is increased by 23% and 25.9 kW respectively when operating one cool resource under the load rate of 80%,compared with operating two cool resources;when increasing the design temperature and humidity to 26℃ and 60% respectively,the energy consumption amount of the HAVC system is reduced by 6%,compared with the data when the designing temperature is 25% and the humidity is 50%.