tailieunhanh - Solar Cells Dye Sensitized Devices Part 10

Tham khảo tài liệu 'solar cells dye sensitized devices part 10', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 262 Solar Cells - Dye-Sensitized Devices Fig. 27. Comparison of I-V curve due to temperature change Fig. 28. Performance changes due to temperature change Fig. 29. I-V curves of DSC due to Focus length Development of Dye-Sensitized Solar Cell for High Conversion Efficiency 263 The changing efficiency of the DSSC by solar concentration rate was measured at varying focal distances with the prepared lens and stage. Figure 29 shows the I-V line diagrams for each solar concentration rate. When the focal distance was 80mm and the solar concentration was at the maximum of 2 543 the cell efficiency was . Focuce Length mm Fig. 30. Performance changes due to focus length Figure 30 shows the maximum output for each focal distance and the voltage and current changes in percentages at the maximum output to determine the factors influencing efficiency improvement. The maximum output increased as the solar concentration rate increased indicating cell efficiency improvement. It was found that the increase of current Imp by solar concentration had a direct influence. Conclusions This study investigated the changes in efficiency when concentrated solar radiation with high energy density was applied to DSSC to determine the factors influencing efficiency. Imp increased as the cell temperature increased and dropped from 45 C while Vmp decreased as temperature increased. The efficiency of DSSC at changing temperatures was investigated when high heat was generated by solar concentration and the highest efficiency was obtained at 45 C. As temperature increased over this value the cell efficiency dropped sharply. Thus a cooling device is essential when manufacturing a power generation system using solar concentration. The high energy density obtained by solar concentration increased the efficiency of DSSC by times on average and up to by absolute value. Because current density can be increased by solar concentration it is possible to implement solar cells with a high .