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Utility Bill Calibration Test Cases

The diagram below illustrates the utility bill calibration test cases in BESTEST-EX. In these cases, participants are given input ranges and synthetic utility bills. Software tools calibrate key model inputs using the utility bills and then predict energy savings for the different retrofit cases. Participant energy savings predictions using calibrated models are compared to NREL predictions using state-of-the-art building energy simulation programs. For self-testing, participants should not view reference results until after tested software results have been generated.

This diagram provides an overview of the BESTEST-EX utility bill calibration case process. On the left side of the diagram is a box labeled "BESTEST-EX Document" with a list that contains two bulleted items. The first bullet reads "Defines a representative existing home and several retrofit measures." The second bullet reads "Provides input ranges for key model inputs." Underneath this list is an image of a house and to the right of the house is a listing of the measures: R-wall=4.5-6.2; ELA=137-216 in2 ; Tsat=60-75°F, etc. Underneath this grouping is another bullet that reads "Presents utility bills that were generated by: A) randomly selecting key model inputs within ranges (values remain hidden); B) running test cases with selected inputs in EnergyPlus, DOE2.1E, and SUNREL." Below this bullet is a bar graph showing energy savings on the y axis and retrofit measure on the x axis. Inside the graph area is text reading "Reference results remains hidden for utility bill calibration cases." An arrow labeled "Results" points horizontally to the right to the results box. From the top half of this box are two arrows that are labeled "Input Ranges" and "Utility Bills" and points horizontally to the right to another smaller box that is labeled "Audit Software Provider." Underneath this heading are three bullets: one reads "Creates model of existing home knowing input ranges from test," the next one reads "Calibrates model inputs using utility bills," and the third one reads "Predicts retrofit energy savings. Underneath these bullets is an image of a house; to the right of this is a bar graph showing energy savings on the y axis and retrofit measure on the x axis. From this box an arrow labeled "Results" points directly below to another box showing a bar graph comparing the simulation results of a number of retrofit measures with the reference results. The energy savings is on the y axis and the retrofit measure is on the x axis.

Back to BESTEST-EX Web page.