Short Term Energy Monitoring: What Does This Information Mean to the Facility Energy Manager?

Abstract

Engineers at the Energy Systems Laboratory at Texas A&M University have completed short term energy metering studies at a complex of offices in northern Texas and several buildings on the Texas A&M University campus during the past 18 months. These studies typically consisted of installing electrical metering at the, whole building level and included sub-metering of selected circuits when possible. Personnel would go through the entire facility ensuring that all lighting, fan, and mechanical systems were active and on. After a period of approximately 10 minutes, a selected areas of the building would be "turned off." This sequence was repeated for all areas of interest in the facility. At the end of the lighting test, air handlers, then chilling and pumping equipment was turned off (if applicable) and a final ten minutes of electrical use data taken. In each of these facilities, lighting system load verification was the primary goal and the data provided a very good accounting for all buildings studied. The northern Texas office buildings in particular, were interested in these data for comparison with a recently hired performance contractor. The A&M study was a follow-up to an earlier lighting study that had been conducted by the campus energy office. Base electrical load data was also determined from these tests. This paper presents results of these studies and suggests that the method is attractive to both contractors and facility energy managers as well.