**Appendix A**

**Figure A1.** Hierarchical forecasting for power generation: electrical subsystem *versus* generating source.

**Figure A2.** Hierarchical forecasting for power generation: electrical subsystem *versus* generating source.


**Figure A3.** Hierarchical forecasting for electricity generation based on the ARIMA procedure (RMSE, MAE, MASE). (Note: The performance was indicated into a color scale, where green means better values for calculated accuracy, and red means worse accuracy. The intermediate values are colored yellow.).


**Figure A4.** Hierarchical forecasting for electricity generation based on the ETS procedure (RMSE, MAE, MASE). (Note: The performance was indicated into a color scale, where green means better values for calculated accuracy, and red means worse accuracy. The intermediate values are colored yellow.).
