The UK has the 'pay commercial users who are able to voluntarily reduce demand' system too, and that was part of the initial response to the frequency drop, I t

The UK has the 'pay commercial users who are able to voluntarily reduce demand' system too, and that was part of the initial response to the frequency drop, I think. The problem is that the volume of demand you can get rid of this way isn't necessarily enough to be sufficient -- if you need to dump 10 or 20% of demand and especially if it needs to be spread evenly over the grid then it's going to be hard to do without disconnecting people involuntarily. I wouldn't be surprised if we could do better in the volume of demand we could reduce on demand, especially with smarter technology, though. At some point the question is whether the extra complexity and infrastructure is cost-effective to avoid once-a-decade events on the scale of this one, which probably 90% of the UK would never have noticed unless they read the news...