Uncertainty and sensitivity decomposition of building energy models

Abstract

As building energy modelling becomes more sophisticated, the amount of user input and the number of parameters used to define the models continue to grow. There are numerous sources of uncertainty in these parameters, especially when the modelling process is being performed before construction and commissioning. Past efforts to perform sensitivity and uncertainty analysis have focused on tens of parameters, while in this work, we increase the size of analysis by two orders of magnitude (by studying the influence of about 1000 parameters). We extend traditional sensitivity analysis in order to decompose the pathway as uncertainty flows through the dynamics, which identifies which internal or intermediate processes transmit the most uncertainty to the final output. We present these results as a method that is applicable to many different modelling tools, and demonstrate its applicability on an example EnergyPlus model.

Keywords:

• uncertainty analysis
• sensitivity analysis
• decomposition methods
• EnergyPlus

Acknowledgements

The authors would like to thank Dr. Sophie Loire for generating some of the scripting for the simulations on the computer cluster. This work was partially supported under the contract W912HQ-09-C-0054 (Project Number: SI-1709) administered by SERDP technology program of the Department of Defense. The authors also thank the project leader Dr. Satish Narayanan (UTRC) for technical guidance.