More than 18,450 Maui Electric customers experienced a power outage at 4:03 p.m Thursday.
Areas affected by the power outage included West Maui, Kahului, Haiku, Kihei, Wailea, Hana and Upcountry.
Maui Electric spokesperson Shayna Decker said the outage occurred when a generating unit tripped offline at the Maalaea Power Plant.
She said the cause of the shift offline is under investigation.
Decker said power was restored to a majority of customers by 5:04 p.m.
“Currently, we are waiting for more generation to be available to restore remaining customers,” she said at around 9 p.m. Thursday.
Decker said when the Maalaea generating unit tripped, it caused the electrical frequency on the system to drop suddenly, prompting a “load shed” to various parts of the island to protect the entire electrical system.