Implementation of Smart Operation Strategies for Air-Conditioning and Lighting Systems for Ministries Complex in the State of Kuwait

摘要

The smart operation strategies were implemented for Air-Conditioning (A/C) and lighting systems to reduce the national load at Ministries Complex (MC) in the state of Kuwait. The A/C system in MC is a district cooling system that comprises of 8 chillers with water-cooled condensers and four circuits of chilled water distribution with their independent pumps feeding to 184 air-handling units (AHUs), including 26 independent fresh air units. Total connected load of A/C systems is 8,867 kW, while fan motors of AHUs account for 2,390 kW. Lighting system in MC comprises mostly of energy efficient T12 fluorescent tubes and compact fluorescent lamps with a total connected load of 2,254 kW. Pre Closing Treatment (PCT) between 13:00 and 14:00 h, when the building was still occupied, was explored. Fresh-air AHUs were closed at 13:00 h instead of 14:30. Also, Time-of-Day Control (TDC) for AHUs and lighting systems along with the cooling production and cooling distribution systems was applied between 14:00 and 15:30 h, in line with the building occupancy for each building at MC. PCT and TDC schemes for chillers, AHUs and lighting systems were carried out through the Building Automation System (BAS). Implementation of the smart operation strategies for A/C and lighting systems was successful at MC. The temperature build up did not exceed 1?C during PCT scheme and the temperature did not exceed 28?C during TDC scheme. The savings in peak load demand were 610 kW between 13:00 and 14:00 h, 4,500 kW between 14:00 and 15:00 h, and 6,897 after 15:30 h. The reduction of 4,500 kW at 15:00 h is equivalent to $7.6 million towards constructing power plant and distribution network. Savings of 13,720 kWh in daily energy consumption was achieved due the implementation of the smart operation strategies. These savings led to a reduction of $1,500 per typical summer day of the MEW fuel bill and 8,918 kg/day of CO2 emissions. To make MC building more energy efficient, it is recommended to retrofit AHUs and secondary chilled water pumps with variable frequency drives (VFDs).