This study investigates the real-world energy performance of appliances and equipment as it compares with models and test procedures. The study looked to determine whether DOE and industry test procedures actually replicate real world conditions, whether performance degrades over time, and whether installation patterns and procedures differ from the ideal procedures. It first identifies and prioritizes the appliances to be evaluated. Then, the study determines whether real world energy consumption differed substantially from predictions and also assessed whether performance degrades over time. Finally, the study recommends test procedure modifications and areas for future research.