Distribution transformer size optimization by forecasting customer electricity load

For power utilities, determining an efficient transformer size for a power customer is a challenge depending on the many different specifications of the structure or area being developed by the client. Supplying a transformer much larger than necessary to a customer adds capital costs to a project, as well as increased future costs of transformer losses. Under-sizing a transformer for a client leads to reliability issues and an unsatisfied customer. Analysis shows the financial benefits of accurately sizing transformers, based on a study conducted on a group of three-phase pad-mounted transformers at Black Hills Power Utility in Rapid City, SD. By researching existing customer electricity use, a method of forecasting electricity load is developed and applied.