Using a solar chimney to keep a comfortable temperature in your home can be a reliable, energy efficient alternative to using electric heat. Conversely, a solar chimney can be used to cool the home during the hot summer months as a cheap alternative to air conditioning. Solar chimneys work by using air that has been collected in a closed in space and heated by solar energy. Quite simply, the age-old solar chimney consists of a black-painted hollow stack. When the sunlight is at its strongest in the afternoon, the penetrating rays heat the chimney and the air inside it, resulting in an updraft of air circulating inside the structure. The suction present at the base of the stack is used to cool the attached building. In our society, it is easier to simply open a window and let the wind blow into cool our rooms, but in areas of the world where the hot summer days are windless they use such a chimney is the only method of adequately ventilating the homes.
If one wishes to construct a solar chimney, it is essential to remember that the chimney must be higher than the roof in order to function properly, and must be positioned on the side of the house that faces the sun mid-afternoon. It must be constructed of a glazed material that absorbs heat well, and the larger the surface area, the more effective the chimney is in the air exchanging process. Lastly, it is critical that the chimney not face the direction of prevailing winds. For superior home cooling, one may construct the chimney in such a way that incoming air is led through a tunnel of underground ducts before it enters the building; the cold, deep earth further cools the air. It can be difficult, albeit costly, to maintain your home’s temperature using electric heat. With the rising costs of electricity today, many families are looking for safe, inexpensive ways to aid in heating the home. For home heating purposes, a solar chimney can be constructed with a trombe wall, that is, a wall built from a material that absorbs sunlight that faces the sun, so that the chimney reverses in the cold weather and aids in keeping the home warm instead.