Impact evaluation for the Manufactured Housing Acquisition Program: Technical appendix

Abstract

Portions of this document m y be iliegibie in electronic image products. Images are produced from the best available original document. DISCLAIMERThis report was prepared as a n account of work sponsored by a n agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, make any warranty, express or implied, or assumes any legal liability or mponn'bility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or sem'ce by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necesSarily state or reflect those of the United States Government or any agency thereof. EXECUTIVE SUMMARYThis report supplements Lee et al. (1995), which presents the findings of an impact evaluation of the Manufactured Housing Acquisition Program (MAP). Pacific Northwest Laboratory conducted the evaluation and prepared both reports.This report presents detailed technical information relevant to the MAP impact evaluation. It ,is intended to provide the interested reader with enough information to answer most technical questions about the analysis and results. TIERED ANALYSIS APPROACHWe used a three-tiered process to analyze the energy consumption of both MAP and baseline homes. The information from each analysis was useful for designing our final analysis. \The first approach was a comparison of annual billing data, followed'by a simplified regression analysis to adjust for major home characteristics. We compared the mean annual kWh consumption of MAP and baseline homes, and used the'difference to estimate energy savings. We made no adjustments for long-term weather.This first analysis showed that MAP homes consumed less electricity than the baseline homes used in our analysis, but the differences were'less than the pre-program estimates suggested. We identified several factors to examine further. First, nonelectric supplemental heating was more common in baseline homes than in MAP homes. Second, in some cases heat pumps were more common in baseline homes than MAP homes and they tended to reduce energy consumption. Third, the average baseline home in our sample was smaller than the average MAP home, thus reducing the difference between electricity use in MAP and baseline homes. Fourth, we found that the distribution of total electricity consumption and consumption per square foot in MAP homes exhibited less variance than in, baseline homes.The second-tier approach was an application of the PRlnceton Scorekeeping Method (PRISM). This methodology uses monthly billing data to estimate coefficients that can be used to predict the non-temperature-and temperature-sensitive portions of energy consumption. W...

Impact Evaluation for the Manufactured Housing Acquisition Program (Map)

“…This difference, however, is very consistent with the findings from numerous other evaluations that examined pre-program estimates (Brown and Mihlmester 1994). We have reviewed the pre-program analysis (see Lee et al 1995) and find that several factors might contribute to the difference between those results and ours. The following list is not a critique of the original analysis, but suggests reasons why the pre-MAP results might differ from ours and areas for possible research to explain the differences:…”

“…As noted earlier, regional investor-owned utilities (IOUs) also conducted an energy analysis of MAP and non-MAP homes during late 1994, and these results also were available for comparison. The comparisons are discussed briefly in this report and in more detail in Lee et al (1995).…”

“…Two other reports supplement this overall report on the evaluation. Lee et al (1995) provides technical details of the study. Sandahl, Lee, and Chin (1995) presents detailed information about the home owner survey conducted for this evaluation.…”

“…Because many of the appliance and equipment end uses respond to climate variations or vary seasonally, we adjust them (see Lee et al 1995) to account for their expected seasonal variations. We use data from the Bonneville Power Administration's Regional End-Use Metering Project (REMP) to supply these adjustments (Cahill, Ritland, and tin-Kelly 1992).…”

“…The monthly load allocation factor for the indicated appliance (see Lee et al 1995) A dummy variable indicating household income is less than $25,000 per year First, because no true control or comparison samples are available for estimating energy savings, we define a comparison home based on typical characteristics. The "pre-MAP baseline" home represents a home with dimensions typical of current homes, but with an efficiency level typical of homes built prior to the MAP and Super Good Cents Program: we assume that the envelope conductance value is a U, of 0.098.'"'…”