Decision-making on PV Modules for Very Large Scale Photovoltaic Systems Using Improved Analytic Hierarchy Process

Analytic hierarchy process (AHP) was performed on decision-making of PV modules for very large scale photovoltaic systems using sc-Si, mc-Si, a-Si, CdTe and CIS from both economic and environmental viewpoints. The amount of module, land requirement, transportation, array support and foundation varies depending on the type of PV module because of the differences of price and efficiency. In order to objectively reflect those changes and to avoid the uncertainty of the pair-wise comparison due to the subjectivity of personal judgment, the classical AHP method was improved as following: (1) Quasi-optimal matrix was introduced to meet the demands of accuracy, simplicity, rapidity and consistency. (2) Weights factors were readjusted to their contribution to the criteria of the previous level, depending on the previous cost and life-cycle analysis results of VLS-PV systems done by IEA/PVPS Task 8. From the AHP results, we obtained a conclusion that mc-Si was the optimum option for the assumed 100 MW VLS-PV power generation system which was to be installed in the Gobi desert. From the analysis procedure we could see that the analytic hierarchy process provided an analyzed tool effectively for the project appraisal and the decision-making on PV module for VLS power generation systems. The analytic hierarchy structure and its weights might be further modified according to the future project requirements.