Sustainable Energy, 2013, Vol. 1, No. 2, 26-31 Available online at http://pubs.sciepub.com/rse/1/2/3 © Science and Education Publishing DOI:10.12691/rse-1-2-3 Numerical Simulation for Achieving Optimum Dimensions of a Solar Chimney Power Plant M. Ghalamchi 1,* , M. Ghalamchi 2 , T. Ahanj 3 1 Department of Energy Engineering, Science and Research Campus, Islamic Azad University, Tehran, Iran 2 Faculty of New Sciences &Technologies, University of Tehran, Tehran, Iran 3 Faculty of Nuclear Engineering, University of Shahid Beheshti, Tehran, Iran *Corresponding author: Mehrdad.Ghalamchi.mech@gmail.com Received November 01, 2013; Revised November 23, 2013; Accepted December 05, 2013 Abstract Renewable energies are playing a fundamental role in supplying energy, as these kinds of energies can be clean, low carbon and sustainable. Solar chimney power plant is a novel technology for electricity production from solar energy. A solar chimney power plant derives its mechanical power from the kinetic power of the hot air which rises through a tall chimney, the air being heated by solar energy through a transparent roof surrounding the chimney base. The performance evaluation of solar chimney power plant was done by FLUENT software by changing three parameters including collector slope, chimney diameter and entrance gap of collector. The results were validated with the solar chimney power plant which was constructed in Zanajn, Iran with 12 m height, 10 m collector radius and 10 degree Collector angle. By simulation and numerical optimization of many cases with dimensional variations, increasing 300 to 500 percent of chimney velocity and eventually increasing output power of system was observed in different cases. Keywords: renewable energy, solar chimney, numerical simulation, Zanjan Cite This Article: M. Ghalamchi, M. Ghalamchi, and T. Ahanj, “Numerical Simulation for Achieving Optimum Dimensions of a Solar Chimney Power Plant.” Sustainable Energy 1, no. 2 (2013): 26-31. doi: 10.12691/rse-1-2-3. 1. Introduction According to the shortage of the current energy resources and increasing the global energy demand and also, regarding to this reality that the energy obtained of the fossil fuels is environment damaging and nonrenewable, the demand of achieving a technology for exploitation of clean and renewable energies is sensed. Solar chimney power plant is one of the proper options for using the clean energy resources. The solar chimney technology is designed for preparing energy in large scales. In this type of power plant, the solar energy and subsequently the air movement are used. The air flow cause turbine rotation and the rotation is converted to electrical energy by a generator. The conceptual design of solar chimney power plants was first propounded by professor Schaich in 1978 [1]. Before 1980, the system was built as an experimental sample in Manzanares, Spain [2]. The chimney diameter, collector radius, and height of the sample were 10 m, 122 m, and 194.6 m, respectively. The maximum output power of the system reached to 41 KW in September, 1982. Since then, many researchers became interested in this work and studied the related technologies for the high potential and vast applications of solar chimney power plants. Yan et al. [3] and Padki and Sherif [4] have done some of the Preliminary study on the thermo-fluid analysis of a solar chimney power plant. In 1983, Krisst built a 10 W, 6 m collector diameter, 10 m height chimney in US [5]. In 1997, a chimney was built in Florida University and the plan was optimized for two times [6]. In aspect of small scales, a model with 0.14 W outlet power, 3.5 cm chimney radius, 2 m height, and 9 m 2 collector areas was built by Klink, Turkey [7]. Pretorius andKröger [8], Ninic [9], Onyango and Ochieng [10] investigated the influence of a developed convective heat transfer equation, more accurate turbine inlet loss coefficient, quality of collector roof glass, and various types of soil on the performance of a solar chimney power plant. Ming et al. [11] evaluated the temperature and pressure fields for air in solar chimney power plant. More investigation and simulations have been carried out by Lodhi [12], Bernardes et al. [13], Bernardes et al. [14], von Backstro ¨mand Gannon [15], Gannon and von Backstro¨m [16], Pastohr et al. [17], Schlaich et al. [18], Bilgen and Rheault [19]. The efficiency of solar chimney power plant was investigated according to the previous works. Since the practical measurements are much difficult, the simulation methods would be much easier for efficiency prediction of the different models of solar chimneys. Generally speaking, different combinations of chimney and collector dimensions can be built for purpose of electrical power production. Considering the cost reduction, that is much important that the optimized combination of chimney- collector dimensions would be known for the prediction.