The chief, Herman Andaya, cited his health in stepping down. His agency’s decision not to sound emergency sirens as wildfires neared Lahaina had drawn scrutiny.
The sudden departure comes a day after the chief defended not using outdoor alert sirens. The official death toll has reached 111 people and is expected to climb.
The utility company’s share price has tumbled after lawsuits were filed seeking to hold it accountable for the blaze, which has killed more than 100 people.