การวิเคราะห์การกระจายตัวและแนวโน้มดัชนีองศาวันความเย็นรายภูมิภาคของประเทศไทย

อภิวัฒน์ ชัยสุกัญญาสันต์; พงศกร คชาพงศ์กุล; สิริชัย จิรวงศ์นุสรณ์

Authors

อภิวัฒน์ ชัยสุกัญญาสันต์ นักศึกษา,วิทยาลัยพลังงานและสิ่งแวดล้อมอย่างยั่งยืนรัตนโกสินทร์ มหาวิทยาลัยเทคโนโลยี ราชมงคลรัตนโกสินทร์, 96 ถนนพุทธมณฑลสาย 5 ศาลายา อำเภอพุทธมณฑล นครปฐม 73170
พงศกร คชาพงศ์กุล อาจารย์ที่ปรึกษาร่วม, วิทยาลัยพลังงานและสิ่งแวดล้อมอย่างยั่งยืนรัตนโกสินทร์ มหาวิทยาลัยเทคโนโลยีราชมงคลรัตนโกสินทร์, 96 ถนนพุทธมณฑลสาย 5 ศาลายา อำเภอพุทธมณฑล นครปฐม 73170
สิริชัย จิรวงศ์นุสรณ์ อาจารย์ที่ปรึกษาหลัก, สาขาวิชาวิศวกรรมโลจิสติกส์ คณะวิศวกรรมศาสตร์ มหาวิทยาลัยเทคโนโลยีราชมงคลรัตนโกสินทร์, 96 ถนนพุทธมณฑลสาย 5 ศาลายา อำเภอพุทธมณฑล นครปฐม 73170

Keywords:

Cooling Degree Day Index, Building Energy Consumption, Thailand Climate

Abstract

This study aims to develop a CDDs map covering all six regions of Thailand based on daily average temperature data from 2020-2024 for six representative provinces. The base temperature of 25 °C was applied in accordance with ASHRAE standards for hot–humid climates. The results reveal that the Central and Eastern regions exhibit the highest CDDs values of 1739 and 1732 respectively, while the Northern and Northeastern regions record the lowest values of 1206 and 1175. The national average CDDs increased by 5.9% over the five-year period, reflecting the influence of global warming and a continuing rise in cooling energy demand. Linear regression analysis indicates a negative correlation between altitude and CDDs (R² = 0.51, p = 0.11, t = –2.07), suggesting that lowland areas require greater cooling energy compared with highland areas. Regions with higher CDDs, such as the Central and Eastern regions, should adopt thicker insulation and stricter OTTV/RTTV criteria under Thailand’s Building Energy Code (BEC) than regions with lower CDDs. The outcomes of this study can be applied to energy conservation planning and the design of energy-efficient buildings in Thailand.

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