Dive Brief:

• A power outage affecting the capital of Puerto Rico and surrounding areas cut electricity service to 800,000 residents on Thursday, according to the territory's state-owned utility. 
• The Puerto Rico Electric Power Authority said on Twitter that a transmission fault in the south of the island caused generators at the Aguirre, Palo Seco and San Juan power stations to shut down, cutting electricity to the north and east of the island. Crews are assessing the line to restore it to service this afternoon, the utility said.
• The outage comes five months after Hurricane Maria destroyed the territory's power grid, leading to a lengthy and contentious recovery effort. Before the outage, about 15% of the island residents still lacked power, according to government statistics. 

Dive Insight:

Puerto Rico's latest power major outage was caused by a fault in a 230 kV transmission line between the towns of Salinas and Aguas Buenas, PREPA said on Twitter.

The line moves power from the 450 MW Aguirre Generating Station in Salinas to the capital of San Juan. The fault also caused caused the 600 MW Palo Seco and 400 MW San Juan generating stations offline due to a lack of generation resource adequacy. 

PREPA did not return requests for comment, but interim Executive Director Justo González said in a video on the social network that crews are attempting to reroute power through other lines and assessing the affected transmission in hopes of restoring it to service this afternoon. 

While three PREPA-owned generators in the region are offline, two 450 MW plants owned by AES and EcoEléctrica remain online, utility officials told El Nuevo Día. The paper also reports the affected transmission line was targeted, without success, for repairs by Whitefish Energy, the Montana-based contractor that was controversially awarded a power restoration contract in the aftermath of Hurricane Maria. Anonymous PREPA sources told the paper two other transmission lines also went out of service. 

The outage comes weeks after a federal judge approved a $300 million loan for grid upgrades at the bankrupt utility, short of the $500 million it requested. PREPA has $9 billion in debt, is under the financial control of a federally-appointed oversight board, and is slated to be sold to a private owner under plans announced by Gov. Ricardo Rosselló.