Evaluating the Influence of Intermittent Weather Condition on the Effectiveness of Solar Photovoltaic System: The Case of Ntyuka Transmission Station

Abstract

Conventional fossil-based power generation has increased global 
electrical output but introduced environmental stress, cost 
volatility, and resource depletion. Solar photovoltaic (PV) systems 
offer a feasible low-emission option; however, their efficacy is 
intrinsically affected by nonlinear factors associated with solar 
irradiance and module temperature, rendering weather variability 
a significant operational limitation. This study assesses the impact 
of intermittent weather conditions on the performance of the 
standalone 6 kW PV system at Ntyuka Transmission Station in 
Tanzania. Measured site parameters—including hourly global 
horizontal irradiance, module surface temperature, system 
component specifications, and recorded AC output power—were 
incorporated into a MATLAB/Simulink model representing the PV 
array and inverter configuration. Model validation was performed 
by comparing simulated system behaviour against measured 
operational data under varying environmental scenarios. Results 
indicate that fluctuations in irradiance from 1200 W/m² to 700 
W/m² lead to significant voltage and power reductions, 
contributing to an average energy loss of 18–22%. The study 
confirms that intermittency reduces system efficiency, output 
stability, and supply reliability. The findings highlight the need for 
improved system control strategies, optimised sizing, and 
supportive policy measures to enhance the technical viability of 
off-grid PV systems in Tanzania.