This study provides the first long-term outdoor degradation assessment of three silicon-based photovoltaic (PV) technologies; monocrystalline (m-Si), polycrystalline (p-Si), and amorphous/microcrystalline silicon (a-Si); operating for more than eleven years (2014-2025) in the semi-arid climate of Marrakech. Using over 132 months of AC production data, the performance indicators (Yf, Yr, PR, eta sys) were analyzed using Linear Regression (LR), Classical Seasonal Decomposition (CSD) and Seasonal-Trend decomposition using Loess (STL) to isolate long-term aging trends from seasonal variability. Results show that crystalline modules exhibit comparable long-term stability, with annual degradation rates of 1.337 +/- 0.136%/year (p-Si) and 1.350 +/- 0.14%/year (m-Si) using LR, increasing to 1.593 +/- 0.09%/year (p-Si) and 1.589 +/- 0.09%/year (m-Si) with CSD after removing seasonal effects. Amorphous technology shows significantly higher degradation: 2.683 +/- 0.142%/year (LR) and 2.850 +/- 0.11%/year (CSD). Daily yield ratios reveal that p-Si maintains a persistent advantage of 2-4% over m-Si, while a-Si diverges after 1150 days, stabilizing at a long-term deficit of 14-16% relative to crystalline modules. Lifetime projections indicate that p-Si and m-Si reach the 80% end-of-life threshold after 17-18 years, whereas a-Si reaches it after only similar to 9 years. Economic analysis shows that p-Si achieves the lowest LCOE (10.15 cUSD/kWh), followed by m-Si (11.00 cUSD/kWh) and a-Si (14.61 cUSD/kWh). These results provide robust long-term experimental evidence on PV reliability in hot semi-arid climates and support improved technology selection and lifetime modelling for North African solar deployments.