Riddhi Chaturvedi
Independent Researcher
India
Abstract
This paper analyzes the solar radiation potential available for rooftop photovoltaic (PV) installations in a representative metropolitan region in 2015. The objective is to quantify the spatial and temporal distribution of global horizontal irradiance (GHI) and direct normal irradiance (DNI) using data obtained from ground-based pyranometers and satellite-derived solar maps available up to 2015. Statistical methods, including descriptive statistics and correlation analysis, are employed to assess variability and to identify optimal roof orientations. The findings indicate that south-facing roofs with tilt angles between 20° and 30° receive the highest annual insolation of 4.8–5.2 kWh/m²/day. Limitations in data resolution and local shading effects are noted. Recommendations are made for refining roof-level assessments and integrating meteorological forecasts to improve PV output predictions.
Keywords solar radiation, rooftop photovoltaic, global horizontal irradiance, direct normal irradiance, statistical analysis
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