Techno-economic study for a 50 MW PV plant in Nigeria

Abstract: As part of Nigeria’s drive to increase electricity production capacity and shift to renewable sources, a new 50 MW photovoltaic (PV) plant is proposed for a town in north-west Nigeria. Rather than using conventional monofacial modules and fixed mounting, it is of interest to consider a selection of new technologies which are attracting growing attention in the global utility PV market. These can increase energy output, and could be used to advantage in this 50 MW plant. However, the technologies, namely bifacial modules and solar tracking, are more expensive than their conventional counterparts, while their relative performance depends on the latitude and climate of the plant location. Thus their economic benefit cannot be taken for granted. The aim of this study is to propose multiple designs for the 50 MW plant using different combinations of module and mounting technologies, finding their economic order of merit by estimating their respective levelised costs of electricity (LCOEs).Using the simulation software PVsyst, the electricity production of different plant layouts and component configurations was estimated. Key parameters such as tilt angle and pitch distance were varied in order to optimise each configuration of technologies. Having sourced economic data from the industry and literature, lifetime plant costs were calculated, which in combination with lifetime electricity production, were used to estimate the LCOE.As expected, results indicated that the optimum configuration was bifacial modules mounted on horizontal single-axis tracking (SAT), followed by monofacial modules on horizontal SAT. Fixed installations had greater LCOEs by a reasonable margin, while the LCOE difference between monofacial and bifacial modules on fixed mounting was within the error of the calculation, meaning this choice relies on more accurate input data. A sensitivity analysis allowed uncertainty in the results to be gauged, and highlighted the factors which most influence LCOE, so that efforts to increase profitability can be focussed in the right places. Finally, suggestions are offered to help optimise bifacial and tracking installations by comparison with conventional plants.The conclusions drawn herein will be specifically relevant to the Swedish developer and EPC contractor Svenska Solenergigruppen which, in due course, will submit a plant design proposal to the project developer of the 50 MW plant. However, it is hoped that this work will act as a guide for any EPC contractor or developer working on a utility PV plant in sub-Saharan Africa, allowing efficient design of an optimal system.