The Energy Department published final energy efficiency requirements Thursday for distribution transformers, standards meant to pursue the administration’s goal of making power grids more efficient and resilient, while also taking into account concerns raised by industry and labor groups over its stringent emissions requirements and time frame.

According to the final rule, transformer cores will now be required to be made with 75% amorphous steel — down from its originally proposed 95% requirement. Manufacturers will also have five years, rather than three, to comply.