校園教室環境最佳舒適度與能源消耗之研究

Abstract

本研究以實驗方式探討校園教室環境中的空氣品質、舒適度與能源消耗並對其做平衡，使用架設運用Wifi作為無線傳輸方式的中華電信prius智慧系統之交通大學工程五館132教室，空氣品質定義二氧化碳800ppm以下為舒適，800-1000ppm為可以接受，1000ppm以上為不舒適；舒適度定義PMV在-0.5以上和0.5以下這區間為舒適；能源消耗以使用一節課五十分鐘內消耗多少度電為基準，改變實驗參數比較分析何者環境或控制方法能在教室人員舒適的情況下達到最大的節能效果。實驗參數可分為不可控參數：教室人數(24-88人)、人員分佈、人員使用類型(上課與考試)、室外溫度(22-34℃) 、天氣(晴、雨與風)。可控參數：固定溫度控制(24-27℃)、演算法自動控制、人工手動控制、門窗開關。實驗前20分鐘開啟空調。 其研究結果顯示，未控制情況，人員使用132教室時為開門關窗和空調定溫25度。考試時二氧化碳濃度高於上課時，且超過35人時二氧化碳濃度會超過1000ppm，使人不舒適，開窗且有風時能有效改善濃度，但是考試時濃度仍會超標。自動控制演算法在維持PMV為舒適的情況下，比定溫25度節省17.7-28.0％的能源消耗。一般情況下建議定溫26度，比定溫25度節省6-18.7％的能源消耗。

This study experimentally investigates and the indoor air quality, energy consumption, and thermal comfort of the classroom environment. The control is based on the Prius smart system from Chunghwa Telecom via Wifi connection. The classroom for testing is at room 132 of Engineering Bldg. 5 at NCTU. The designated class room condition for indoor air quality for carbon dioxide to be lower than 800 ppm is regarded as comfort, 800-1000ppm is acceptable, and a concentration above 1000 ppm is regarded unacceptable. For thermal comfort, PMV from -0.5 to 0.5 is considered as comfort. Based on the comfort PMV, an algorithm is developed to meet the demand of minimum energy consumption while maintains the thermal comfort. In addition, the corresponding indoor air quality (carbon dioxide) is investigated during balancing the thermal comfort and energy consumption. Experimental parameters can be divided into uncontrollable parameters and controllable parameters. The uncontrollable parameters include the students attending the class (24-88 people), students distribution in the classroom, conditions of classroom (normal lecture class or examination), outdoor temperature (22-34℃), weather (sunny, rainy, or windy). Tests were performed conditions subject to class room temperature (ranging from 24 to 27℃), automatic control, manual control, operation with opening in doors or windows. The results show that students generally adopts 25℃ temperature as the set point of air-conditioner while leave the door opening and closing window. It is also found that the concentration of carbon dioxide rises more quickly during examination than normal lecture course. The concentration of carbon dioxide will exceed the standard 1000 ppm when more than 35 people attends the class. Opening the window and the wind can effectively improve the carbon dioxide concentration. However, the concentration is still above the unacceptable threshold. For energy consumption, through the using particle swarm optimization algorithm, the derived automatic control can meet the demand of thermal comfort which reduce energy consumption as much as 17.7-28.0% than the original air-conditioner self-regulating at 25℃. In general, the fixed temperature of 26℃ is better than the fixed temperature of 25℃. In fact, it can reduce 6-18.7% of energy consumption