Study on Design Method of Energy-Saving HVAC System Considering Building Scale Characteristics in Urban Medium-sized Office Building and its Effect Verification

Abstract This study verified the design method of Energy-Saving HVAC System, predicted the energy saving effect, and verified the energy saving effect after completion in a medium-sized urban office building. The energy-saving equipment system, which was considered the characteristics of medium-sized urban office buildings, includes a fluctuation/ductless sharing air conditioning system, a total circulation type heat recovery ventilation system that recovers heat from restroom exhaust by spraying hypochlorous water, a natural ventilation system, a high-efficiency heat source control system at low loads to prevent a decrease in efficiency during long periods of low load, air conditioning using medium-temperature chilled water, and water sprinkling on heat source equipment. During the operation phase, performance verification was carried out for three years after completion using cloud BEMS, and tuning and operational improvements were carried out. By implementing ZEB operation while checking the impact on the indoor environment through questionnaire surveys, it was confirmed that primary energy consumption was 440 MJ/m2-year in the second year of operation, achieving a reference ratio of 0.43.