The power outage

[giza]

There has been a lot of itneresting talk about the power outage and what may have caused it. First, I found this article on Slashdot where the poster explains how powergrids interconnect utilities:

The Niagra Mohawk power grid serves the area in question. The way a power grid works is that there is a mesh of generation stations that are all interconnected by high-voltage transmission lines, 480kV on up. Each generation station has a primary service area and one or more (usually more) entry/exit stations where energy can either enter or exit the primary service area, depending on what they're telling the control system to do.

A network of generation stations makes up a grid, and at the boundary of a grid, there are similar entry/exit stations.

All generators, whether they be nuclear, hydro, wind, or whatever, have TONS of safety interlocks that engage at various points during abnormal conditions to prevent catastrophic failure. One of these interlock behaviors is to shut down and remove the generator from the grid in the event of an overload.

The likely sequence of events in this situation is that there was a failure at one of the generators in the N-M grid that resulted in the shutdown of that generator. What happens when a generator shuts down is that all of the entry/exit points flip to "entry" mode to allow neighboring generators to take up the slack. Most generator companies have agreements with their neighbors to buy however much electricity they need at whatever the current price is, without acknowledgement, when one of these shutdown events happens.

Anyway, once the initial generator shut down and the entry/exit stations flipped to entry mode, the neighboring generators were unable to take up the slack, so they in turn shut down as well. Then, a domino effect set in until it reached the boundary of the N-M grid, or when someone at the operator station woke up and hit the red button that prevents the transfer stations from automatically flipping to "entry" mode.

Keep in mind that it didn't necessarily have to be an overload that caused it - a generator can shut down for a number of reasons.

Then, this other post talked about some of the non-technical reasons that could have contributed to this problem. The poster talks about deregulation and how it has affected the user of power grids. Originally, when power grids were first built, each local (regulated) utility had plenty of capacity. The power grid would only be used if a single utility had a significant outage.

However, with the advent of deregulation, the companies are mostly interested in turning a profit for their shareholders (like any good company should be). This in turn has led to the logic of "why build expensive local plants that may not be used often when we can buy electricity from other suppliers instead?". Now the grid is being used to transmit electricity across long distances, which the poster claimed the grid was never intended for. So, when there was a local outage like on Thursday afternoon, the other grids were unable to meet the load, and they begane shutting down one by one for the reasons above.

Finally, I saw this article, and I found the line of thinking in it to be disturbing, to say the least. The author's "solution" to the power problem was to, "never vote for a democrat again". See, the Democrats are the cause of all that is evil, and the Republicans are all a bunch of good guys. Yep, really. My GOD, it sure must be nice to have such a simple answer to all of society's problems and not be burdened down with that nasty process of rational thought. If I ever wind up like that, somebody shoot me!

Comments

Failure and recovery.

[cjthomas.livejournal.com]

Two things that I don't understand:

• Why isn't there limiting logic that only allows export of power when there's capacity to spare? That would stop cascading outages in their tracks. This or something like it was _supposed_ to have been implemented after the similar cascading failure in the 1960s.
  
  
• Why the heck did it take the better part of a day to get power back up, especially in Toronto, with two nuclear plants within a hour's drive? Under any sane conditions, wouldn't they just disable all grid interconnections and start powering known-safe areas back up?
  

Power not being distributed represents money lost even to a privatized system, so I can't fathom point 2 even if you assume that the gross design oversight of point 1 makes sense (e.g. because the grid was not intended for routine power transfer).

[unciaa.livejournal.com]

> However, with the advent of deregulation, the companies are mostly interested in turning a profit for their shareholders (like any good company should be).

Unfortunately, profit of shareholders doesn't necessarily equate good of the customers or employees of that company, so I'm not sure the "like any good company" applies.