In a statement PNG Power says the load shedding is to repair ageing equipment at Boroko sub-station.
PPL says the recent introduction of NiuPower into the Port Moresby grid has led to load shedding exercise due to lack of compensating reactive power to meet demand.
Negotiations with NiuPower to adjust their generator settings have seen a reduction in load shedding from two feeders to one per day, as well as reducing load shedding hours from seven to five.
Several other causes of power outages in NCD include a minor electrocuted while trying to vandalize a power pole, two major line falling at Marianville Secondary and Erima Wildlife, and a technical fault on one of the Rouna Four Power Station.
Meanwhile, Power Poles were sabotaged in the Siane area of Simbu Province, resulting in part of Kundiawa, Ban, Mt Hagen, and Wabag experience power outage.
PPL said it is currently carrying out preventative maintenance to this equipment.