Thomas Patzner and Wendell Leisinger Schneider Electric, Nashville, Tenn.

Calculating the “Real” Cost of Ownership for Transformers

View the full story , including all images and figures, in our monthly digital edition Specifying a transformer is often a balancing act—you want it to be both energy-efficient and cost-effective to operate, but you also have to take the client’s budget into account, as well as the total costs of ownership over the building’s lifetime. In recent years there has been some confusion in the marketplace due to mixed messages about energy-efficient transformers and their viability for commercial building projects. The National Electric Manufacturers Association (NEMA) chose a 24-hr average loading of 35% for its TP1 transformer standard in 1996, an energy-efficiency level that was subsequently adopted by the U.S. Dept.