TBATS achieved the lowest RMSE and MAE of all 13 models. This isn't a coincidental result — TBATS is purpose-built to handle exactly the conditions this dataset presents: multiple overlapping seasonalities (daily and weekly), complex cyclical structure, and nonlinear patterns that single-seasonality models like SARIMA or ETS can't fully capture. Fourier Regression ranked second, which makes sense since it also explicitly models multiple periodicities through harmonic terms. SARIMA still performed competitively, which is a useful finding in its own right — it shows classical seasonal ARIMA remains a solid, interpretable choice for structured load data even when it isn't the top performer.