Energy saving analysis of buildings cooling district energy system

• Main Authors: Ming-Yi Chen, 陳明義
• Other Authors: Yew-Khoy Chuah Ph.D.
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/px2jf4

碩士 === 國立臺北科技大學 === 能源與冷凍空調工程系碩士班 === 103 === In Taiwan often due to different ownership, air-conditioning systems are usually separately installed for buildings, zones, and floors. There the air-conditioning systems have to meet the separately cooling and heating schedules even the buildings are in the vicinity of each other. The design of district energy center so that a central system can supply a group of buildings is rather rare. The research of this thesis primarily focuses on energy saving by replacing the chillers of a building group of three that belong to a corporation, situated in a technology park in northern Taiwan. The objective is to analyze the efficacy and identify the advantages and disadvantages, before and after the chiller replacement and the centralized cooling system design. Due to the actual retrofitting, this study analyzed only the energy performance of chillers and the water side system. Thirteen old chillers were replaced and three new larger higher efficiency chillers were installed for a centralized cooling system. The centralized system at the energy center, function to allocate the resource and required redundancy for the building group. Therefore the operation of the chillers can be maintained at high energy efficiency and decrease the energy consumption of the buildings. The results showed that the power requirement for the chillers could be reduced from 3,083 kW to 1,404 kW after the retrofitting. Energy saving of 26.86% was achieved with annual saving of about 2,371,067 kWh. The correspond reduction of carbon emission was 1,261,408 kg(C02/yr). The energy saving was evaluated by EEWH-RN, the green building rating for existing buildings, according the calculations provided by the Architecture and Building Research Institute of the Ministry of the Interior. The “Carbon Reduction Evaluating Method” was used to calculate the Carbon Reduction Ratio (ΔCRr). ΔCRr was calculated to be 20.9 %, equivalent to a Bronze certification.