Supplement to the determination analysis (ORNL-6847) and analysis of the NEMA efficiency standard for distribution transformers

摘要

This report contains additional information for use by the US Department of Energy in making a determination on proposing energy conservation standards for distribution transformers as required by the Energy Policy Act of 1992. An earlier determination study by the Oak Ridge National Laboratory determined that cost-effective, technically feasible energy savings could be achieved by distribution transformer standards and that these savings are significant relative to other product conservation standards. This study was documented in a final report, 'Determination Analysis of Energy Conservation Standards for Distribution Transformers' (ORNL-6847, July 1996). The energy conservation options analyzed in this study were estimated to save 5.2 to 13.7 quads from 2000--2030. The energy savings for the determination study cases have been revised downward for a number of reasons. The transformer market, both present and future, was overestimated in the previous study, particularly for dry-type transformers, which have the greatest energy-saving potential. Moreover, a revision downwards of the effective annual loads for utility owned transformers also results in lower energy savings. The present study assesses four of the five conservation cases from the earlier determination study as well as the National Electrical Manufacturers Association energy efficiency standard NEMA TP 1-1996 using the updated data and a more accurate disaggregated analysis model. According to these new estimates, the savings ranged from 2.5 to 10.7 quads of primary energy for the 30-year period 2004 to 2034. For the TP-1 case, data were available to calculate the payback period required to recover the extra cost from the value of the energy saved. The average payback period based on the average national cost of electricity is 2.76 years. 15 figs., 23 tabs.