 The LEED-NC (New Construction) rating system credited the stadium with 40 points toward certification, the highest total of any LEED-certified park in the majors—the retro-contemporary ballparks of Oracle Park, Target Field and Nationals Park are the only others to achieve LEED certification.Although they were publicly seeking silver, Loria had privately challenged engineers to shoot for the higher gold certification.The most difficult aspect of achieving gold, though—and one the design team had doubt it would be able to accomplish—was concerning the energy required to operate the retractable roof.