The potential of solar chimney for application in rural areas of developing countries

Solar chimney electric power generation is one of the concepts in renewable energy technology (RET) application. The power station is based simply on the principle that warm air rises. Air underneath a glass ceiling is heated by solar radiation and rises through a chimney. The warm air which has just risen is replaced by air from the edge of the glass ceiling which flows inward, and will then itself begin to heat up. In this way the Sun's heat radiation is converted into kinetic energy of constantly rising air to drive turbine built into the chimney. The turbine then converts the wind power by means of a generator into electrical energy. We have considered the appropriateness of a solar chimney to rural villages and highlight some features of such a power generating plant. The calculations carried out show that the power that can be generated by a solar chimney of specific dimension exhibit a minimum threshold value of tau = 2.9, the temperature ratio of the difference between the collector surface temperature and the temperature at the turbine (T-s-T-H) to the difference between the air mass temperature under the roof and the collector surface temperature (T-m-T-s). Our calculations show that for tau = 2.9, an appreciable electric power (>= 103 W) can be generated by a sturdy and physically viable solar chimney whose dimension has been determined to be L = 150 in, H = R = 1.5 in. This the minimum dimension of a practical solar chimney electric power station would serve approximately fifty (50) households in a typical rural setting. (c) 2006 Elsevier Ltd. All rights reserved.