Optimizing NEMA TP 1 transformers for process industry substation service

NEMA has established a voluntary efficiency standard, under which NEMA Class I transformers are required to meet certain efficiency standards as set forth in their specification TP 1-2002. The U.S. Department of Energy, acting as required by the Energy Policy Act of 1992, is considering the establishment of mandatory efficiency standards for distribution transformers. Some states have established requirements for some transformer applications to meet NEMA TP 1. This paper examines the question: What should be the specification wording to insure that the furnished equipment meets NEMA TP 1 and also is optimized in terms of cost effectiveness for the application?.