Ironically, the first portion of the Coal and Energy forum had just wrapped up when the power went out all across Northern BC.
Bob Gammer, Community Relations for BC Hydro says that they’re still investigating the cause of the outage, though the main suspect is a lightning strike causing a cascading blackout.
Cascading failures, according to Wikipedia, typically occur when one part of the system fails and other parts must then compensate for the failed component. This in turn overloads these nodes, causing them to fail as well, prompting additional nodes to fail one after another. A single point of failure on a fully loaded or slightly overloaded system results in a sudden spike across all parts of the system. “This surge current can induce the already overloaded nodes into failure, setting off more overloads and thereby taking down the entire system in a very short time. This failure process cascades through the elements of the system like a ripple on a pond and continues until substantially all of the elements in the system are compromised and/or the system becomes functionally disconnected from the source of its load.”
Gammer says the problem began at about 9:30, the evening of September 11, and took out power for more than 120,000 people across nearly the whole of Northern BC, including Prince George, Vanderhoof, Smithers, Fort St John, Dawson Creek, Fort St. John, Chetwynd, Hudson’s Hope, Houston, Burns Lake and, of course, Tumbler Ridge.
But Tumbler Ridge is surrounded by wind turbines, producing over 300 MW of power between the three wind farms. How come the lights went out here?
The answer is the grid. All the wind projects—Quality, Meikle and Moose Lake—have power purchase agreements with BC Hydro, who purchase all the power produced by these wind projects.
As part of the agreement with BC Hydro, they cannot produce power when their substation is de-energized.
There are a number of reasons for this, says Jesse Coonce, Site Manager for Capital Power’s Quality Wind Project. The most obvious is safety. The wind power producers feed their energy to the grid. If there are crews working on the grid because the power is out, and there is power feeding through the lines, it creates a dangerous situation.
It is theoretically possible for the town to have its own electrical grid (an “island”) during a black out, but this would create an additional expenses and complications for both the wind farms and BC Hydro, and the contracts with the wind farm expressly prohibits the practice.
So, while the wind turbines were capable of producing energy, they couldn’t feed the power onto the grid until the grid came back on-line.
