* 1. All data presented is for 150C temperature rise copper transformer
2. No Harmonic Mitigating Transformers, Guard or transformers with K factor greater than 1 are considered
3. It is assumed that all the transformers have the same load profile
4. The expected life of the transformer considered is 25 years
5. No demand cost is considered
6. The operation cost just considers the energy costs of the transformer. Maintenance or service costs are not included
** Transformers manufactured after 2007 meet a government required minimum performance standard known as TP-1. CSL -3 is a higher performance standard set by the Department of Energy.