HECO has filed a notice of intent with the commission, said Lynne Unemori, vice president of corporate relations. She could not pinpoint when the full, detailed filing would be made, but said it would be soon. Unemori also would not disclose the proposed rate increase, which would have to be approved by the commission.

"At this point, we are still finalizing that," she said. "It is really important to note that when we do actually submit the filing, that is just the first step. Then it goes through a long review process by the PUC. And that takes close to a year before there is even a potential for them to issue a decision."

The increase is needed to pay for capital improvements and maintenance, she said.