"So we need to do what we can to minimize those vulnerabilities by ensuring that we can isolate portions of each one of those interconnects," he said, adding that "there are physical security issues that certainly have to be dealt with. I think the biggest risk is potentially attacks on the system at those critical nodes."
What Wellinghoff describes is already being accomplished on a smaller scale with distributed generation and microgrids that can be islanded in the event of an emergency.
Smaller systems increase reliability because their flexibility allows them to continue to function when separated from the larger system. This is because a microgrid is a complete and functional electric generation and distribution system that can stand alone. It's a "mini-grid."
Microgrids can be connected to each other, as well as to the larger, centralized grid, however they may also be disconnected in event of emergency to prevent centralized problems from affecting their operation.
Our traditional centralized generation system for electricity relies entirely on the transmission/distribution system to function. Any faults in the T&D system cause blackouts for end users because the fault causes this system to lose its generation component and become incapable of generating electricity for the end users.
Increased reliance on long haul transmission lines to distribute renewable energy thousands of miles from point of generation to point of use increases the risk of failure for end users. The most reliable system is one where generation of electricity occurs as close to the point of use as possible. Less wire, less risk of failure.
So while Wellinghoff's reasoning is sound, his application is short-sighted because it doesn't look beyond the traditional centralized generation grid.