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Abstract: Climate change and rising electricity demand have driven the need for energy efficiency in buildings. Single-family residential buildings present significant opportunities for improvement, but current strategies for identifying savings are labor and capital-intensive. Developing a residential version of virtual energy audit tools like EDIFES offers a cheaper, non-intrusive alternative.

This study used data from 25 all-electric homes in Florida to refine algorithms from EDIFES, originally designed for commercial buildings. The analysis utilized one year of 15-minute interval electricity consumption data, along with square footage, number of floors, and location. These markers include heating and cooling type, setpoint setback, HVAC load, pool pump detection, refrigeration load, and effective Rvalue. The heating and cooling type marker uses linear or segmented models based on daily consumption and outdoor temperatures. The type of heating and cooling systems were correctly identified in all but one building. A 1°C shift in setpoints resulted in an average 10% annual reduction in electricity consumption. The setpoint marker also estimated HVAC load with an 11% mean error, with 40 of 50 cases having errors under 20%. Pool pump markers, designed for constant-speed pumps, used kernel density to calculate their size and detected their presence with 100% accuracy. Validation with submeter data showed a 4.2% average error in load prediction. Reducing pump schedules to five hours per day led to a 21% reduction in pump load while replacing pumps with variable-speed models resulted in a 23% reduction in whole-home consumption. The refrigeration load marker identified cyclical loads, mainly from the compressor, with a 15% error. However, expected savings are minimal due to the small size of the refrigeration load. Effective R-value was calculated using consumption and temperature data. If R-values were below ASHRAE 90.2 standards, insulation improvements were simulated to quantify potential savings.

Surprisingly, few buildings had lower-than-desired R-values, indicating a need for further study to refine the assumed parameters. The largest and most cost-effective savings came from pool pump replacements and setpoint setbacks. Replacing pumps requires a modest investment but offers significant savings with a quick payback. Setpoint setbacks involve no capital cost and provide immediate savings.

Thesis Committee: Alexis Abramson (Chair), Roger French, Charles Sullivan, Vikrant Vaze