This paper shows the detailed results of different particle-based and nanocrystalline TiO2 films prepared by sol-gel technology using precursors with different pH and autoclaving at different temperatures to produce dye-sensitized solar cells (DSCs). The thickness of the TiO2 film in the DSC was optimized as well. The designs of DSC modules, using series and parallel connections, will be shown in the paper, and the two designs will be compared. Current-voltage characteristics of DSCs with different sizes will be presented, and results will be reported for modules having a size of 15 x 20 cm(2) and an active area larger than 60%. The photoelectric conversion efficiency of the modules was more than 5%. (C) 2004 Elsevier B.V. All rights reserved.