بام خنک: تجربه اى در خنک کردن بام از طریق تغییر رنگ

نوع مقاله : علمی - پژوهشی

نویسنده

مربی دانشکدة معماری و شهرسازی دانشگاه شهید بهشتی

چکیده

مصرف انرژى یکى از مهم ترین شاخص ها در جهان امروزى است. به این موضوع مى توان از زوایاى متفاوتى نگریست. از طرفى مصرف بیشتر انرژى به معناى تولید بیشتر و  یا صنعتى بودن کشورها بوده و از طرفى دیگر موجب آلودگى بیشتر محیط زیست خواهد شد . افزایش گازهاى گلخانه اى، گرم شدن کرة زمین، آب شدن یخ هاى قطبى، و صدمه دیدن لایة ازن از عوارض آلودگى محیط زیست هستند. همچنین افزایش هزینه هاى انرژى ، بار مالى بیشترى را بر کشورها تحمیل می کند. یکى از مصر ف کنندگان عمدة انرژى ساختمان ها هستند. در این پژوهش نقش رنگ در کاهش مصرف انرژى مطالعه میشود و با آزمایشات انجام شده محقق می گردد که تغییر رنگ بام (سقف) حدود 17 ٪ به خنک شدن داخل ساختمان ها و درنتیجه کاهش مصرف انرژى منجر میگردد. براى کاهش مصرف انرژى در ساختمان ها روش هاى متفاوتى را مى توان به کار گرفت، از تغییر زاویة جهت گیرى ساختمان ها تا عایق کارى و یا تغییر مصالح، لکن فعالیت تغییر رنگ در مورد ساختمان هاى موجود به سادگى قابل حصول و با هزینه اى بسیار کم و در برخى موارد بدون هزینة اضافى قابل دستیابى است.

کلیدواژه‌ها


عنوان مقاله [English]

The Cool Roof Experimenting with Change of Color to Cool the Roof

نویسنده [English]

  • Farshad Razmgah
Lecturer, Faculty of Architecture and Urban Planning, Shahid Beheshti University
چکیده [English]

In Iran, some 22 percent of the building energy dissipates through the roof. In the hot arid parts of the country, most of this energy is used for cooling rather than heating. There are several methods for reducing this energy loss. Insulation is one popular method throughout the world. A more effective method is to reduce the energy penetrating the building by means of cooling the roof. There are three main techniques for obtaining a “cool roof”. In the first method, heat loads are reduced by lightening the color of the roof, hence increasing its albedo. In the second method, the “green roof”, the roof is suffused with vegetation, which is more expensive and technically complicated. In the third method, the roof is sprinkled with water. In this method, a significant amount of water is wasted, however. Because of its inexpensiveness and simplicity, the first method was chosen for an experiment, in which part of a dark green roof was repainted with brilliant light green. The daily summer temperatures were then measured on an hourly basis and compared with the shaded areas of the roof as well as areas covered by plants. The results indicated that the repainted areas were about 17 percent cooler.

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