Technical and economic comparison of various electrical collection grid configurations for large photovoltaic power plants

In this study, a technical and economic comparative analysis for evaluating the performance of various electrical photovoltaic (PV) plant configurations is presented. This methodology assessment is based on a holistic approach that calculates the levelised cost of energy (LCOE) considering the capital and installation cost of the PV components, as well as, the operation and maintenance costs over the lifetime of the project. Also, the potential economic impact of the installation of batteries for providing flat-output response is investigated. Moreover, a sensitivity analysis is included for considering both economic and technical uncertainty on the LCOE. The presented methodology compares the performance of six different configurations in three hypothetical PV power plants (1, 50 and 200 MW) located in Golden, Colorado, USA. The results obtained demonstrate that although some PV power plant configurations present better efficiency (higher performance ratio), they are not the most cost-effective solutions because of the requirement of extra equipment or the inclusion of expensive technologies. Finally, the benefit of including batteries into the system is shown for flat output operation. The results show that in spite of their inclusion increases the LCOE, extra revenues can be obtained when providing such services.