The calibrated energy simulation gives the owner and facility operator a true picture of savings from the ECMs instead of the predicted savings from the energy model developed during design. A simulation model developed during design makes a lot of assumptions on occupancy patterns, set points and weather. A calibrated energy model replaces those assumptions with real data while accommodating unforeseen program changes. If the actual results are greater than 10% from the predicted ones, compare the differences between the assumptions and the actual settings. Calibration is a great learning opportunity for the modeler to verify those assumptions with actual data. After the first year, you do not need to recalibrate the model, instead using energy usage from utility bills to compare against energy usage from previous years. The calibrated model is compared to the actual energy consumption rates and changes need to be made to the model until acceptable calibration is achieved. After all calibration adjustments have been made to the as-built energy model the same changes need to be made to the baseline energy model.
