I wonder if this power failure was due to renewables, wind and solar, only providing 6% of electricity on the 13th.
Daily Telegraph reporting gas was supplying 72.5%, Nuclear 10%, wood burning 6.6%, wind 5.8%, solar nil and the rest from interconnecter cables..
If it had been there would have been major disruption on the grid not just a small part of Cornwall.
Perhaps a permanent standby generator would be a better option than having to source one during a failure of supply to what appears to be a location of considerable importance to the railway in Cornwall?
Given modern battery technology perhaps even a large standby battery. Standby generators are notoriously unreliable (as machines don't like standing idle).