In a data center, the main challenge is dealing with the power consumption of IT equipment and air conditioning (AC) units. To reduce the total energy in a data center, many techniques and approaches have been proposed. These strategies focused on the idle power of servers or controlling AC units while considering the temperature of server racks independently. In this paper, an active controlled shutter that enables the control of cooling airflow was proposed while considering the temperature of servers independently. By using the proposed method, wasted cooling energy could be eliminated. In a simulation of the proposed method, a conventional task assignment method was used, and start-up delays were considered. Additionally, the effect of the active controlled shutter was evaluated. The shutter blocks off cool air from cold aisles by observing the temperature of a server. As a result, the cooling power of the AC can be reduced by preventing the excessive cooling of idle or shut-down servers. An experimental result shows that the proposed method reduced the cooling energy by 22.8 %.