If they shut down one of the reactors unexpectedly, it could have caused instability on the grid and the cascade of blackouts.
That’s certainly not impossible.
What would be impossible is for them to both be up again. You can essentially flip a switch to shut down a nuclear plant, but bringing it back online is a very careful and lengthy process.
Seems like a simple load balance issue. Having more generation than can be absorb by the grid can cause a cascade pretty easy. Some sub-grids got too much and some too little. In either case there are trips. This really does not seem to be a big deal unless you are in traffic in Dade County with millions of Juan Pablo Montoya types. But it is never considered safe to drive in Dade.
last year:
Arizona Nuclear Plant on Lockdown
PHOENIX (AP) — The nation’s largest nuclear power plant was put on lockdown Friday after a contract worker entered the facility with something that security was “not comfortable with,” a spokesman said.
Security officials detained the worker at the Palo Verde Nuclear Generating Station and were conducting an investigation. The incident was considered an “unusual event” — the lowest of four emergencies the plant can declare, said Jim Melfi, an inspector with the U.S. Nuclear Regulatory Commission.
Officials did not say what the worker brought to the plant. There was no threat to the public, said Palo Verde spokesman Jim McDonald.
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