Because small scale breakdowns are irrelevant with today’s power grids. Redundancy is provided via the next city/country nearby. Importing the power might be a few cents more expensive during peak hours, but that’s nothing compared to the costs of having an outdated power plant doing nothing for years.

However, the real answer why he’s being down voted is because it’s a pretend intellectual argument favoured by people against renewable power generation, without actually contributing anything of worth.