Too Much Stick? Not Enough Carrot? Testing the Presumption of Non-Compliance

Panel: Residential Buildings: Technologies, Design, Performance Analysis, and Building Industry Trends

Authors:
Eric Swan, RLW Analytics
Jarred Metoyer, RLW Analytics
Wim Bos, Sacramento Municipal Utility District

Abstract

This paper reports the findings of an evaluation study of the 2006-2007 Sacramento Municipal Utility District (SMUD) Residential HVAC1 Retrofit program. The program's savings calculations assumed that 96 percent of non-participant retrofits in their territory are not complying with California's ambitious 2005 energy code to some degree2.

The evaluation study included comprehensive performance testing and cooling season long system monitoring of 60 program participant homes and 50 homes that had recently replaced their HVAC systems but did not participate in the program. Additionally, a telephone market survey was conducted to estimate the annual HVAC unit replacement rate in SMUD's service territory as well as to identify qualified non-participants. The evaluation team visited the building departments that have jurisdiction over SMUD's territory to determine whether nonparticipants identified through the survey had pulled a building permit for their HVAC unit replacement.

Using the non-participant units as a baseline, SMUD's TIER 13 participating units save 532 kilowatt-hours (kWh) per year. Approximately 62 of the 532 kWh/yr are attributed to equipment efficiency, and the remaining savings is ascribable to tighter ducting systems, closer to optimal refrigerant charge and system airflow, and better system sizing.

The results of the market survey show that there are approximately 7000 non-participant annual AC replacements in SMUD territory. If all of these 7000 replacements would have overall system performance similar to SMUD's TIER 1 participant units, there is a potential savings of 3,724,000 kWh per year, only accounting for a single year's savings of a single year's AC replacement population.