Energy-Efficient Dry-Type Distribution Transformers: New Opportunities to Cut Energy Bills and Lock-in Long-Term Energy Savings

Abstract

Nearly 90% of the electricity that powers the industrial sector flows through dry-type distribution transformers. These transformers are very efficient- most convert in excess of 95% of input power to output power. However, because transformers are generally energized 24 hours per day, 365 days per year, even small efficiency improvements can yield big energy and dollar savings for power users. Until now, energy-efficient dry-type transformers have been hard to identify. As a result, most users either have failed to specify efficiency at all or relied on the imperfect indicator of low temperature rise. Most manufactures have not offered an "energy-efficient" product line. Now, the National Electrical Manufacturers' Association (NEMA), the transformer manufacturers' trade association, has published a standard defining energy-efficient transformers. This new standard, NEMA standard TP-1, makes it easier for vendors, specifiers, contractors and end-users to identify and determine the cost-effectiveness of energy-efficient transformers. In addition, some manufacturers are beginning to offer equipment lines specifically designed to meet the energy efficiency levels defined in NEMA standard TP-1.