Transformer

Any movement of electrically charged material in physical space has the potential to induce an electric charge in nearby material.

This electromagnetic phenomenon is exploited in the transformers that power the world's electric grids. The electricity delivered by utilities is alternating current, which means that the polarity of the charge regularly changes, as described by a sine wave. Each second for the electricity of the North American grid, sixty of these alternations occur. A properly-constructed transformer may achieve efficiencies of 99%.


a large oil-filled transformer in Manitoba painted in a typical deep green