There is a new challenge for the Transformer Industry in 2016: The US Department of Energy (DOE) has determined that higher transformer energy efficiency standards will result in significant conservation of energy. With new amendments to existing standards, electrical losses are expected to drop by about 8 percent for liquid-immersed transformers, 13 percent for medium-voltage dry-type transformers, and 18 percent for low-voltage dry-type transformers.
In addition, about 265 million metric tons of carbon dioxide emissions will be avoided, equivalent to the annual greenhouse gas emissions of about 52 million cars.
Core losses are a result of an alternating magnetic field in the transformer core, and dictated by core material and design. The loss generated for a given material is a function of operating frequency and total flux swing. These are due to hysteresis, eddy current and residual loss. Those values can be drastically reduced by using the right grades of steel with the right design, and proper manufacturing of the core assembly.