외기냉수냉방 시스템의 에너지 절약효과에 관한 연구

Abstract

Recently the cooling load in buildings is increasing even in winter. Free cooling can be a very energy efficient way for buildings that are high in cooling load all year round. In this research economical aspects of free cooling and problems of operation were studied through surveys of buildings that need all year round cooling load. Through TRNSYS simulation program, energy using patterns of free cooling system combined with other cooling systems are compared and energy saving effects of free cooling system are reviewed. Also energy conservation variables that effects the building energy cost were set and analyzed. The results are as follows, 1) Energy savings are high in December to March. 2) It is desirable to apply Free Cooling system to where the continuous inside heat gain is occurred. 3) Free Cooling system can be operated efficiently when web bulb temperature of outside air is below 8℃. If systems can be operated with automatic control system, Free cooling system can save more energy. 4) Using lower approach temperature in heat exchanger is suitable for saving energy.