07 Alternative energy sources (solar energy) temperature distribution obtained by computer simulation is compared with experimental results which were obtained in previous work for a typical summer day (l/7/1992) in Tanta, latitude 30"47'N, Egypt. Good agreement between experimental and theoretical results is observed. The boiling and characteristic boiling times of the cooker are decreased by 50 and 30%, respectively, on using the cooker around midday. 98lOO453 A close-form solution for the maximum-power operating point of a solar cell array Alghuwainem, S. M. Solar Energy Materials and Solar Cells, 1997, 46, (3), 249-257. The paper states that a solar cell array is inherently a non-linear device consisting of several solar cell modules connected in series-parallel combinations to provide the desired d.c. voltage and current. At a fixed insolation level, the terminal voltage decreases non-linearly as the load current increases. As a result of this non-linearity, analytical determination of the operating point at which the output power is maximum, a condition required for maximum utilization efficiency of the array, is difficult. Iterative techniques are normally used to determine this operating condition, but this is lengthy, time-consuming, and requires repetition for any change in the array's parameters,
temperature, and insolation level. In this paper, an accurate closed-form solution is derived in terms of the array's parameters and solar insolation level. This solution is useful as a fast and accurate tool for system design and performance analysis.