Energy Fiji Limited has introduced temporary power rationing in some areas to manage electricity demand until full transmission capacity is restored.
EFL confirms that people in affected areas may experience outages lasting between two to three hours during this period.
A tentative timeline for full restoration of power supply across Viti Levu will be released later today.
Power supply disruptions continue to affect Viti Levu due to adverse weather conditions associated with Tropical Cyclone Vaianu.
EFL says a fault on the main 132kV transmission line between Wailoa and Cunningham triggered a major outage across Viti Levu last night.
While the 132kV transmission line from Wailoa to Vuda has since been re-energised, repair works are ongoing on affected 33kV circuits.
EFL teams are also inspecting distribution lines, with undamaged lines being restored and faulty ones scheduled for repairs.
They say repair work on the Wailoa–Cunningham line is expected to be completed by tomorrow.
Due to the damage, power supply in the Central Division remains severely limited.
EFL further says extensive damage to its network has impacted a large number of customers, however, multiple teams are working simultaneously across Viti Levu to restore electricity as quickly and safely as possible.
They add that restoration efforts are being carried out under challenging conditions, including limited access to some affected areas.
Majority of residents in Ba are still without power since yesterday morning.
In Rakiraki, Naria, Rarapatu, Volivoli and Ellington are still without power as well.