PERFORMANCE ANALYSIS AND OPTIMIZATION OF A CONCENTRATED PHOTOVOLTAIC SYSTEM WITH DOUBLE FRESNEL LENSES

Abstract

In this study, the performance of a CPV system with double optical elements using point-focus Fresnel lenses has been analysed experimentally. In this context, the effects of concentration ratios (𝐶1, 𝐶2) and 𝑓- numbers (𝑓1, 𝑓2) of primary and secondary optical elements and distance between Fresnel lenses (𝐿𝐷) on the CPV system performance have been investigated for different configurations with single and double Fresnel lenses. In general, it has been observed that the CPV system performance improves with increasing L_D until it reaches a critical value (L_(D,crit)), but it starts to worsen after L_D exceeds L_(D,crit). It is also notices that L_(D,crit) significantly dependents on the optical properties of the Fresnel lens pairs. Besides this, CPV systems with double Fresnel lenses with a high f_1 value have been seen to perform better than single Fresnel lens applications. It has been detected that the performance of the CPV system can be improved by using a secondary Fresnel lens when f_1>0.5. Beyond these, the ANOVA analyses have been carried out by using the experimental data in order to compare the contribution ratio of the optical properties of Fresnel lens pairs on CPV system performance. The results of ANOVA analysis have indicated that primary optical element properties C_1 and f_1 are predominantly effective on double Fresnel lens CPV system performance. On the other hand, compared with other parameters, f_2 has found to have the least contribution ratio on CPV system performance. Finally, optimum C_1, C_2, f_1, f_2 and L_(D,crit) have been predicted by genetic algorithm and artificial neural network based studies.