A power blackout on Sunday that affected about 90% of Chile’s customers may have been a result of the massively destructive February 27 magnitude 8.8 earthquake. The country’s National Emergency Office (Onemi) said that power had been restored to 98% of the country by Monday—within hours of the outage—but the energy minister noted that the system would remain unstable for up to six months.

The Wall Street Journal reported that on Tuesday, recently inaugurated Energy Minister Ricardo Raineri ruled out rationing electricity on the grid that supplies about 90% of the population. He did, however, ask electricity users to be more energy efficient. (See the Nov. 2009 issue of POWER for a special report on the power sector in Chile.)

A burned-out 500-kW transformer that had been damaged by the quake is being blamed for the blackout. Because restoring power after the quake was a priority, some damaged equipment was returned to service. Raineri said replacing that equipment could take up to six months, during which time the main grid, known as the SIC, would remain vulnerable. The installed capacity on the SIC in 2008 was about 10,226 MW.

Some sources, including Reuters, speculated that the blackout could affect output from the country’s copper mines, which would push copper prices up, because Chile is the world’s top supplier of copper. Not all mines were affected by the blackout, though mines accounting for about 28% of the country’s copper output were affected.

Onemi was still reporting minor earthquakes today.

Sources: Onemi, Santiago Times, Wall Street Journal, Reuters, POWER