Much of Venezuela was thrust into darkness again today after a transmission system failure in state-owned utility Corpoelec's national grid.
The La Arenosa-Yaracuy 765kV sub-station in central-west Venezuela broke down shortly before noon, causing a blackout affecting up to 17 states and much of Caracas.
About two-thirds of Caracas is currently without electricity more than four hours after the blackout was first confirmed by Corpoelec at about 11:30am ET.
The affected states include Anzoategui, Apure, Aragua, Barinas, Carabobo, Cojedes, Falcon, Lara, Merida, Miranda, Monagas, Nueva Esparta, Sucre, Tachira, Vargas, Yaracuy and Zulia.
Today's blackout was the third multi-state blackout in the past 10 days, highlighting the fragile state of the grid. Previous blackouts on 21 September and 14 September that impacted Caracas and up to seven states were also traced to sub-station breakdowns on Corpoelec's main transmission line that connects the 10GW Simon Bolivar (Guri) hydroelectric complex in Bolivar state to the rest of Venezuela.
Venezuelan state-owned oil company PdV, which relies on the grid for almost all of its upstream and downstream operations, declined to comment on any impact.
Corpoelec has over 34GW of installed generation capacity but only generates about 10GW, mostly from Guri and smaller hydroelectric complexes on the lower Caroni River in Bolivar.
Venezuela could become more vulnerable to blackouts if the US tightens existing sanctions to cut off imports of low-sulfur diesel, which is mainly used for baseload and back-up generation. Natural gas, which is also used for some generation in western Venezuela, could also become more scarce if European offshore producers Repsol and Eni are blocked by the diesel measure from picking up Venezuelan crude cargoes as payment for their gas supply.