Understanding Campus Energy Consumption -- People, Buildings and Technology

Colleges and universities in the U. S. spend anaverage of $1.10 per square foot (ft2) on electricity and 18ȼ/ft2 onnatural gas annually. In a typical college or university classroombuilding, lighting represents 31 percent and space heatingaccounts for 28 percent of total energy use, making those systemsthe best targets for energy savings [1]. This study utilizes fiveyears of data enlisting a campus as a test bed to understand theinteractions of people, buildings and technology on energyconsumption and to explore how to reduce peak energy use toreduce costs and benefit the community. The University of Texasat San Antonio (UTSA) has 150 buildings on 850 acres at themain campus and 4 buildings on 18.4 acres at its downtowncampus. Five years of energy consumption data has beenanalyzed using 15-minute interval data accessible from 1 mainmeter and 2 sub-meters, as well as building information andweather data from a weather station immediately adjacent to thedowntown campus. The baseline analyses shows that themaximum campus energy demand occurs on weekdays duringthe day, followed by no-class holidays and weekends. Thedemand is minimum during UTSA holidays when there are fewerstaff and faculty/students present on campus. The study showedthere was a linear correlation between temperature and energyconsumption for the downtown campus, however for theDurango building where the solar panels have been installed, thiscorrelation was negative. Solar panels that have been deployedon the Durango building to help minimize the load during theday, when the electricity consumption is highest. The annualpeak consumption occurs during summer, which is expected dueto the south Texas climate. The energy utilization intensity (EUI) data for the downtown campus shows that UTSA has continuallylowered the EUI since 2010, although the EUIs remain higherthan ASHRAE standard requirements.