10 Largest 20th Century Power Outages


You never miss the power until it’s gone. Power outages are catastrophic when they’re lengthy or widespread — some of the largest blackouts of the 20th century affected millions of people and cost millions of dollars to restore. Here they are:

10. The 1998 Blackout of Quebec


In 1998, the Canadian province of Quebec was engulfed in darkness. The blackout was the result of significant power line damage caused by heavy rains and storms. It affected over a third of the province’s 7.3 million people, and was the largest power outage in over 70 years, producing devastating results. All ground transportation was heavily disrupted, with some people even being stranded underground in train tunnels. Flights were not spared either, with hundreds of people left stranded at the airport. The first night was described as chaotic and terrifying, and by the time power was fully restored weeks later 30 people had died, 1000 had been injured, and hundreds of thousands had been displaced.

9. North East American Blackout of 1965


When a power outage is so bad it’s affecting multiple countries, you know you’ve got a problem. A 1965 blackout caused by an overloaded power supply affected several north and mid-west American states as well as the Canadian province of Ontario. The lights went out for over seven hours, during which millions of people were stranded while multiple cases of looting and vandalism were reported. The blackout led to a restructuring of the way power was provided in the affected areas, and the cause was eventually traced back to the power company, which had failed to sufficiently upgrade its generators.

8. San Francisco Blackout of 1998


For six hours in 1998, the 60 million residents of San Fransisco were left in darkness. The cause of this disastrous event was a short circuit in the main power grid, caused by heavy storms that had hit the region. The storms also shut down a hydroelectric dam, and again chaos briefly reigned as businesses shut down, citizens were left stranded, and looters and vandals took to the night. The government learned lessons and made changes to avoid blackouts in the future, and so far the new system has kept San Fransisco running smoothly.

7. Southern Brazil Blackout of 1999


The 1999 blackout of southern Brazil was, at the time, the largest in human history. Lightning struck an electrical substation in the town of Bauru, which caused a number of circuits to trip and shut down power in parts of Sao Paulo, Rio de Janeiro and many other cities. Generators that relied on the electrical load of these circuits automatically failed because they were receiving very little voltage, and the main power plant couldn’t support the load either. The chain reaction was caused in part by shoddy infrastructure maintenance, as the government was forced to make spending cuts during an economic slump.

6. 1999 Blackout in France


Cyclone Lothar and Martin caused property destruction, death and panic across parts of Europe, and created an electrical failure that affected most of France. The worst cyclone in French history brought down transmission lines and caused large swathes of the country to be without power for three days. Repairing the lines was a grueling and expensive task, and generators had to be brought in from as far as Canada to act as interim power sources. Economic losses were estimated at over 18 billion Euros, and the new record for the largest power disruption in history was quickly transferred across the Atlantic from Brazil.

5. Taiwan Blackout of 1999


The evening of July 29th, 1999 began in Taiwan with the blasting of a warning siren over the city of Taipei. This was followed by loss of electricity across the country, causing widespread speculation and rumor as to what could have caused a nationwide power outage. Speculation ranged from a Chinese invasion to a nuclear attack, but reality was much more mundane — a landslide knocked out pylon cables, creating a domino effect that eventually left millions of people both literally and figuratively in the dark.

4. 1998 Auckland Power Crisis


Auckland, New Zealand found itself without power for a staggering five weeks after the four main cables supplying the city with electricity failed suffered mechanical damage. The cables were repeatedly heated up and cooled down by Auckland’s unusual January weather. The old and poorly maintained cables eventually failed one after the other, forcing the city to use backup diesel generators. The noise of several hundred diesel generators running together led residents to describe the city as a “war zone.”

3. Hurricane Opal Blackout of 1995

Hurricane Opal strikes the Florida Panhandle

In 1995, Florida and Alabama were left in darkness from September 27th to October 6th following the arrival of Hurricane Opal.  Opal formed at the Gulf of Mexico, went through Florida and traveled up Alabama before finally downgrading to a tropical storm in Tennessee. The trail of destruction included broken power lines and damaged electricity stations, causing blackouts. Rescue and restoration efforts were hampered by the floods Opal brought with it, and as a result many people were stuck in their homes without power for days.

2. The 2003 Blackouts of Western North America


You know it’s really hot when a heat wave causes power lines to short circuit. Millions of people in western Canada, northwestern Mexico and the western United States were left without power after a series of blackouts swept through the area in 2003 (we’re cheating with this entry, but it still feels like a long time ago). The six week affair forced the police to the streets to calm restless mobs and discourage looting, while firemen were kept busy putting out blazes and rescuing people from immobile trains and elevators. Industrial damage and economic loss was also significant, and the blackouts prompted debate on the deregulation of electrical utilities and the need for investigations to prevent future disasters.

1. 1996 West Coast Blackout


Anyone with an elementary school science education knows that heat affects metal. We would assume that electrical engineers would keep this fact in mind, but whoever designed Idaho’s power lines apparently let it slip. One of the state’s main power lines overheated and sagged, bringing it into contact with a tree. This caused a protective device on the transmission line to trip the main line, resulting in a series of events that eventually led to a west coast blackout. Whether you call it Murphy’s Law or simple bad luck, millions of people in the west of Canada, the United States and Mexico were left without power. Businesses lost millions as the government spent millions more restoring power to numerous big cities.

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  1. I think the picture accompanying the story on the western blackout of 2003 is actually of the Quebec blackout of 1998, which also affected the northernmost part of New York State. It was caused by an ice storm, which was followed by a period of very weather. St. Lawrence County, NY, where I live, had to replace almost every single power pole (at least 10,000).