Interesting way of doing it.

Eirgrid over here uses some remote switching of loads for crisis situations, if a major generation station were to drop out at peak demand, they can switch out a large number of customers off line who have CHP type installations. They use GSM data links over the mobile phone network to do it.

It's called STAR (Short Term Active Response)

It's designed to protect the grid and stablise the frequency in such an event.