American Electric Co., one of Hawaii’s largest and oldest electrical contractors, has consolidated its Oahu operations into a new headquarters in Central Oahu. The new 7,500-square-foot office and warehouse, which was built on about an acre of land in the Mililani Technology Park, opened on Tuesday. American Electric Chairman Bob Dewitz said the company was based in Honolulu for its first 70 years in business, first in Kakaako and then on Sand Island.