Re: Well, you're leaving
It's the near simultaneous loss of two generators that's the problem, not the nature of the generators
Absolutely, but having been vaguely interested in generating policy for many years, I did wonder if the actual sequence of events was more related to National Grid's policies. Now, I may have completely misunderstood this, but in years previous, they had quite a lot of "generating reserve" - small (or even large) generators that could be brought up to speed very quickly in an emergency, but usually at a high price (note this is different to facilities such as Dinorwig, which are designed to take up short-term peaks).
The reserve I'm talking about was mainly small Diesel generators held as backups by the likes of water companies, maybe a few gas turbines. National Grid had to pay the operators to make them available, and then had to pay through the nose for any capacity that was actually used - small Diesel generators aren't terribly efficient.
In those years, load shedding was seen as a last resort. Switching off the rolling mill heaters of a major steel plant for 15 minutes (load shedding guarantees power won't be forcibly removed for more than a few minutes, and won't then be removed a second time for quite a few hours) probably wouldn't affect production of steel very much, but could be very useful when rebalancing the grid.
Not so many steel plants around these days, and a few years ago (if my understanding is correct) National Grid decided to save a lot of money on standby generators by getting rid of most of this generating reserve. This meant they had to find a lot more users who were willing to be part of a load shedding scheme, otherwise known as Demand Side Response, and I have no doubt that there's no properly-calculated national scheme for setting the frequency sensitive contactors.
Oh, and I believe smart meters are meant to be part of this in the long-term, allowing the grid to disconnect domestic properties as easily as industrial ones...
M.
Biting the hand that feeds IT
