Simulation-Based Analysis of Solar Irradiance for Photovoltaic Energy Generation

Abstract

This paper presents a reproducible, low-complexity simulation framework for characterizing solar irradiation availability and estimating photovoltaic (PV) energy yield under a geographically referenced tropical scenario. Surabaya, Indonesia (7.2575°S, 112.7521°E), is used solely to specify solar geometry; no ground observations, satellite-derived historical irradiation series, or experimental PV measurements are employed. Monthly extraterrestrial horizontal irradiation is calculated from astronomical geometry and multiplied by twelve declared, assumed atmospheric clearness indices. A deterministic set of ten annual multipliers represents illustrative interannual departures rather than actual years. A horizontal 1-kWp PV reference system with a constant performance ratio of 0.78 translates modeled irradiation into electricity. The baseline scenario yields 1,942.68 kWh/m²/year of global horizontal irradiation and 1,515.29 kWh/year of estimated PV electricity, corresponding to a capacity factor of 17.30%. September has the highest modeled monthly irradiation (183.26 kWh/m²), while February has the lowest monthly total (145.29 kWh/m²). A ±20% irradiation sensitivity experiment generates 1,212.23-1,818.35 kWh/year under the fixed-performance-ratio assumption. The work provides a transparent educational and preliminary planning benchmark rather than a site-specific resource assessment; the selected clearness indices, simplified diurnal profiles, and uniform interannual multipliers must not be interpreted as validated climatic patterns.