Hawaiian Electric Co. has nearly 1300 structures on its 28 138-kV transmission circuits that span the island of Oahu. The system is isolated with no interconnections to other utilities. A single structure failure should not cause customer outages, but the system is at an increased risk for overload and outages if additional failures occur. The 138-kV transmission structures generally are one of the following types: wood poles, steel poles, fiberglass poles, aluminum frames, and steel or
Transmission Construction Challenges in Paradise
Hawaiian Electric is addressing aging infrastructure and has begun replacing existing transmission structures.