The major blackouts of all time

Large parts of Bangladesh plunged into total darkness, for over seven to eight hours, earlier this week following a mechanical fault in the national power grid – a not-so-rare worldwide phenomenon. '

Although power cuts of such proportions are not that common around the world there have been instances, even in developed nations, when millions were left in complete darkness due to power supply failures. 

To put things into perspective, the blackout of 30-31 July, 2012, which took place in India affecting over 600 million people, is recorded as the biggest power cut incident ever (in terms of the number of people affected).

Meanwhile, at least 25 districts of Dhaka, Khulna, Rajshahi, and Barishal divisions were hit by the country's biggest power outage – which brought the country to a standstill and made millions suffer – since 2014.

According to the Bangladesh Power Development Board (BPDB) and Power Grid Company of Bangladesh (PGCB), the incident was triggered by a transmission line tripping in the eastern part of the country.

Speaking with The Business Standard, Mohammad Zahurul Islam, chief engineer of Ghorashal Thermal Power Plant, said that power generation at Unit 5 of the plant has remained suspended since the national power grid failure on 4 October.

Since the plant – a  major source of the country's power generation – is powered by gas turbines, once it shuts down it takes about 72 hours to be cooled off.

Out of three units, No 7 has been closed for maintenance since 19 September and unit 4 remains operational. Before the grid disaster, units 4 and 5 were generating between 400 and 410MW per day. 

Zahurul said that they plan to restart the power plant next Monday. Once, the plant is restarted, power generation will resume after seven to eight hours and it will be connected to the national grid by evening, Zahurul said.

It was in November 2014 when Bangladesh suffered from its worst power outage which left the country's entire population without electricity for some 10-12 hours.

The catastrophic power outage is considered to be one of the world's biggest-ever – 3rd in the list titled "The Blackout Report" prepared by Riello UPS, an internationally recognized Italian wholesale UPS company – blackouts affecting around 150 million people.

Whereas the last incident of grid failure happened in several districts on 2 May, 2017. 

The following examples prove that a nationwide grid shutdown can not be seen as an "impossible" event.

Here are the biggest blackouts in history in terms of the sheer number of people affected by it – 

1. India Blackout 30-31 July 2012 (affected 620 million people)
2. India Blackout 2 January 2001 (affected 230 million people)
3. Bangladesh Blackout 1 November 2014 (affected 150 million people)
4. Java & Bali Blackout 18 August 2005 (affected 100 million people)
5. Southern Brazil Blackout 11 March 1999 (affected 97 million people)
6. Turkey Blackout 14 April 2015 (affected 70 million people)
7. Brazil and Paraguay Blackout 10 November 2006 (affected 60 million people)
8. Italy Blackout 28 September 2003 (affected 56 million people)
9. Northeastern USA & Canada USA Blackout 14 August 2003 (affected 55 million people)
10. Argentina, Paraguay and Uruguay Blackout 16 June 2019 (affected 48 million people)

Now here is the list of the three longest electrical outages as measured in customer hours  – 

1. 2013 Philippines Blackout (lasted for 6.3 billion hours and affected 6.7 million people)
2. 2017 Puerto Rico Blackout (lasted for 3.4 billion hours and affected 1.5 million people)
3. 2019 Venezuela Blackout (lasted for 3.2 billion hours and affected 30 million people)