Daily Energy Generation Characteristics of Solar Photovoltaic Systems: A Scenario-Based Intraday Simulation

Abstract

Daily photovoltaic (PV) energy yield is governed not only by the accumulated solar resource but also by its distribution within daylight hours. This study introduces four fully synthetic, reproducible daily sky scenarios to isolate the effects of temporal shape on PV power, energy yield, and short-term ramps. A normalized daylight envelope is multiplied by transparent cloud-transmittance functions at 15-min resolution and converted to output using a 1-kWp reference PV array with a constant 0.78 system performance factor. For clear-sky, partly cloudy, overcast, and intermittent-cloud conditions, calculated daily energy yields are clear sky 5.19 kWh, partly cloudy 4.21 kWh, overcast 2.38 kWh, intermittent clouds 3.81 kWh. The scenario ranking demonstrates that mean attenuation primarily controls daily energy, whereas rapidly changing attenuation governs operational ramps. Temporal aggregation substantially suppresses estimated short-term ramps, emphasizing the dependence of variability conclusions on sampling resolution. All outputs are illustrative simulations without field measurements, calibrated meteorological data, or claims about a specific city. The proposed metrics offer a transparent benchmark for teaching, scenario comparison and the design of future field-based investigations.