Experimental validation and techno-economic assessment of façade-applied photovoltaics for nearly zero-energy building conversion in a Mediterranean climate: A Case Study of the Faculty of Engineering, Damanhur University

This study develops an experimentally supported framework for assessing façade-applied photovoltaic (PV) systems as a strategy for reducing grid-electricity demand and evaluating building energy performance in a Mediterranean educational building. The Faculty of Engineering, Damanhour University, Egypt, is considered as the sole case study. The methodology integrates localized field electrical testing, a weather-adjusted July–August electrical time series, façade specific annual solar-radiation screening, controlled DesignBuilder/EnergyPlus simulations, and a transparent module-cost economic assessment. A field test conducted on 2 July 2026 recorded a mean current of 2.72 A and peak current of 3.57 A, corresponding to mean and peak power outputs of 41.42 and 54.33 W for the conventional PV test. A separate two-point BIPV test recorded a mean current of 8.05 A and mean power of 89.79 W. The weather-adjusted dataset covers 1 July–12 August 2026 at 30-minute intervals for JSM-195SP and JS-190W-Special modules installed at 90° and 30°. Annual solar-radiation screening identified Elevation 1 as the most favorable vertical façade, receiving 1,141.2 kWh/m²·year, while the roof received 1,726.8 kWh/m²·year. The annual building assessment uses 8,760-hour DesignBuilder/EnergyPlus simulations with a common modeled PV façade allocation of 1,123.20 m². A baseline and four PV scenarios were evaluated. JSM-195SP at 30° generated 229,119.60 kWh/year and reduced net grid electricity consumption by 217,663.62 kWh/year (18.93%), reducing Net EUI to 200.70 kWh/m²·year and simulated district cooling by 7.41%. Based on an electricity tariff of 1.95 EGP/kWh and module prices of 6,000 EGP/panel for JSM-195SP and 12,000 EGP/panel for JS-190W-Special, simple module-cost payback periods were 13.03, 100.55, 6.20, and 46.24 years for JSM-195SP at 90°, JS-190W-Special at 90°, JSM-195SP at 30°, and JS-190W-Special at 30°, respectively. Using the 2026 EIB Egypt intermittent-generation factor of 0.498 kgCO₂/kWh, annual avoided operational emissions were estimated at 51.63, 32.20, 108.40, and 70.02 tCO₂/year, respectively. These represent emission reductions and potential carbon-credit quantities subject to applicable certification and additionality requirements. The study does not claim calibrated annual utility validation or whole-building net-zero status; rather, it establishes a reproducible evidence chain linking measured electrical behavior, façade selection, annual simulation, environmental assessment, and investment screening.