Occupancy plays a major role in determining energy use of any building. It plays an even more crucial role in the case of a university classroom building. These buildings are typically loaded with highly variable occupancies that vary from very low during breaks to very high during peak daytime hours in the middle of the semester. This paper presents how an energy simulation model was built and validated and then used to explore the effect of occupancy for a classroom/studio building on the campus of Texas A&M University. The energy model for the building was created using the DOE-2 engine and validated with actual energy consumption data. As constructed building characteristics and occupancy loading data were used in the DOE-2 model. Parametric runs were then completed with the validated energy model for variations in occupancy number, occupancy schedules, etc. With the exception of extremely high occupancy, the results show that all variations in occupancy or schedule resulted in less than a 10% deviation from the actual building performance model. These results demonstrate that though it plays a role in the energy performance of this type of a classroom building, occupancy and occupant schedules do not have a major effect on annual energy performance. The results show that, during the design stage of a building life-cycle, building designers do not need very accurate estimates for the occupancy of the proposed building.
