Andolsun, Simge (2013-07). Small Residence Multizone Modeling with Partial Conditioning for Energy Effieiency in Hot and Humid Climates. Doctoral Dissertation.
Thesis
The purpose of this study is to reduce the energy cost of the low-income households in the hot and humid climates of the U.S. and thereby to help them afford comfortable homes. In this perspective, a new HVAC energy saving strategy, i.e. "partial conditioning" was modeled and its potential to reduce the HVAC energy consumption of the low income homes in Texas was quantified. The "partial conditioning" strategy combined three primary ideas: 1) using historic courtyard building schemes to provide a buffer zone between conditioned spaces, 2) zoning and applying occupancy based heating/cooling in each zone, and 3) reusing the conditioned air returning from the occupied zones in the unoccupied zones before it is returned to the system. The study was conducted in four steps: 1) data collection, 2) baseline design and modeling, 3) partial conditioning design and modeling, and 4) analyses and recommendations. First, a site visit was held to the Habitat for Humanity office in Bryan, Texas to collect data on the characteristics of the Habitat for Humanity houses built in Bryan. Second, a base-line Habitat for Humanity house was designed and modeled based on this information along with multiple other resources including International Energy Conservation Code 2012 and Building America benchmark definitions. A detailed comparison was made between the commonly used energy modeling tools (DOE-2.1e, EnergyPlus and TRNSYS) and a modeling method was developed for the estimation of the baseline energy consumption. Third, the "partial conditioning" strategy was introduced into the baseline energy model to simulate a partially conditioned atrium house. As the occupied zone and the direction of the airflow changed throughout the year in the partially conditioned house, this step required an innovative air loop model with interzonal air ducts that allowed for sched- uled bi-directional airflow. This air loop was modeled with the AirflowNetwork model of EnergyPlus. Fourth, the modeling results were analyzed and discussed to determine the performance of the partial conditioning strategy in a hot and humid climate. It was found that partial conditioning strategy can provide substantial (37%-46%) reduction in the overall HVAC energy consumption of small residences (~1,000 ft2) in hot and humid climates while performing better in meeting the temperature set points in each room. It was also found that the quantity of the energy savings that can be obtained with the partial conditioning strategy depends significantly on the ground coupling condition of the house for low rise residential buildings.
