By Dave Sherwood
HAVANA, March 22 (Reuters) - Cuba said it had begun efforts early on Sunday to restore power after its grid collapsed for the second time in a week amid a U.S. oil blockade that has dealt a major blow to the island's already ailing energy infrastructure.
The grid collapsed Saturday evening at 6:32 p.m. (2232 GMT) after a major power plant in Nuevitas, in eastern Cuba's Camaguey province, failed and went offline, grid operator UNE said, causing a cascade effect that knocked out power to the
nation's approximately 10 million people.
Cuba's energy and mines ministry said early on Sunday it had established microsystems - smaller, closed circuits - in all of the island's provinces to restore power for vital services like hospitals, water supply and food distribution.
The country's two gas-fired power plants, operated by Energas, were running in Varadero and Boca de Jaruco, and electricity had reached the nearby Santa Cruz oil-fired plant, the energy ministry said on social media.
Before daybreak on Sunday, the streets of the capital Havana were almost entirely dark as early risers sat on doorsteps, chatting with neighbors and swatting mosquitoes under mostly clear skies lit by unusually bright stars.
Cellular service and internet was almost entirely unavailable in most areas, leaving many without communication of any kind.
TWICE IN A WEEK
Cuba's electrical grid has been teetering on the edge of collapse and unreliable for months, leaving the island's residents in the dark for hours a day, and sometimes longer, even in better times.
But Saturday's blackout incident marks the third major power outage this month, as a majority of the system went down on March 4 when a key thermoelectric generating plant failed. The power grid also went completely offline on Monday for unexplained reasons.
Cuba has experienced a series of total outages in recent years, but two nationwide blackouts in the space of a week is exceptional.
U.S. President Donald Trump began taking measures to block oil from reaching the Caribbean island after Washington deposed Venezuelan President Nicolas Maduro on January 3. Venezuela had been Cuba's most important benefactor, providing oil to its close ally on favorable terms.
Since then, Trump has cut off Venezuelan exports to Cuba and threatened other countries with punitive tariffs if they sell oil to the island.
Cuba has long blamed the U.S. trade embargo for economic failures including its obsolete power grid, while Washington has attributed the shortfalls to Cuba's Soviet-style command economy.
(Reporting by Dave Sherwood in Havana; Editing by Hugh Lawson)
