Hawaiian Electric Company plans to shutter its aging Honolulu Power Plant within three years.
The move is part of a five-year-plan to try and meet the future power needs of the state by turning to renewable energy sources.
The plant, which is located on Ala Moana Blvd. was built in 1954.
The oil fired generation units are less efficient and will be deactivated along with two units at Waiau and two at the Kahului plant on Maui.
HECO owns the land under the Honolulu Plant but has no plans to dismantle it.
It will be kept as a back-up system in the event of an emergency.
"It is going to be there in the the back yard so to speak. So we will for the near future be keeping it for that reserve possibility," said HECO spokesman Peter Rosegg.
At one time there had been talk of redeveloping the area, but HECO says that is not an option at this point.
The plant is in an area under the jurisdiction of the Hawaii Community Development Authority.
HECO says none of its workers will lose their jobs as a result of the mothballing of the plants.