Small business electricity disaggregation: Where can we improve? Towards increased transparency of appliance modal parameters

Abstract

Small commercial buildings (<50,000 ft2 in floor area) consume 44% of all U.S. commercial primary electricity, with plug loads accounting for 31% of that portion and growing. In response, a bottom-up building energy assessment resource (BEAR) was previously developed as a practical approach to disaggregating building energy use, including plug loads. This article examines the performance of BEAR in estimating plug load consumption, specifically appliance energy consumption, through use of smart meters in two building types, food service and office.Results of the analysis reveal that BEAR is capable of providing building stakeholders with meaningful energy information. Accuracy of BEAR's energy consumption estimates could be improved by 25% to 59% through better data on modal (i.e. appliance operating mode such as standby mode) usage and power demand, respectively. These results stress the importance of detailed modal information, because when modal power information was available the median difference between BEAR and the smart meter measured data was 36% compared with 223% in appliances where modal data was not available. In response to these findings, this study develops and presents energy contour plots, a visual tool for plotting modal usage and modal power in a two-dimensional form of energy consumption contours. Moreover, it is the recommendation of this study that increased transparency of modal power be implemented at the manufacturer label or specification to achieve increased accuracy of targeted energy improvements.