On Thursday, August 14, 2003, just after 4:10 p.m., an estimated 10 million people in Ontario and 45 million people in eight U.S. states were affected by a power outage.

The cause of this massive power grid failure? A tree in Ohio. As millions of people turned on their air conditioners on a hot summer day, some electrical lines heated and expanded near Akron, Ohio. The transmission lines came in contact with foliage. A software ‘bug’ in the energy management control software failed send an automated alert to neighbouring power stations to redistribute the load adequately. This created a vicious cycle of subsequent power stations passing on the overload down the chain. What would have otherwise been a localized blackout cascaded into massive grid failure.

A hot day. A tree. And a software bug…all that is need to disrupt electrical power to 55 million people.

When the power went I out, I was sitting in a coffee shop in a meeting with my boss. Due to franchise rules, the staff informed us that customers are required vacate the premises in the event of a power failure. We were duly ushered outside.

At what point did the tree in Ohio and the software bug ‘connect’ to my life? Was the tree wholly ‘separate’ from my life until the moment it touched the wire? What about the software bug that overloaded the system?

The fact that one tree and a program error in Ohio can suddenly affect the lives of millions of people demonstrates an important principle of complexity: increasing interconnectedness increases the rapidity of change. The more interconnected we are, the higher the chance that a very small event in one part of the system can have significant consequences across the entire system. Interconnectedness increases the speed of change. As the world grows increasingly connected, examples of this proliferate:

Pandemics that would have once been regionally isolated can now spread around the world in mere hours via transoceanic flights.

A natural disaster in one part of the world disrupt commodity and service delivery elsewhere — and therefore economies — in other parts of the world.

Increased social connectedness via social media can facilitate social upheaval, such as the Arab Spring, and the stories and messages of social upheaval in one region can trigger further upheaval elsewhere.

A general observation in complexity: greater connectivity tends to equate to faster change.

Cite this page:
Shelley, James. (2020). 'Blackout' (in System Thinker Notebook). Originally published on August 5, 2020. Accessed on October 31, 2020. Licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Permalink:
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