What is the best action when frequency drops to 59.95 Hz and plenty of generation is available?

When the frequency drops to 59.95 Hz, it indicates a potential imbalance between generation and load on the power system. Ensuring that generators are providing governor response is vital because this response helps stabilize the frequency by allowing generators to automatically adjust their output based on changes in system frequency.

The governor control mechanism enables generators to respond promptly when frequency drops, ensuring they can increase their output and help restore frequency towards the nominal level of 60 Hz. This action is crucial for maintaining grid stability and preventing further frequency decline, which could lead to more severe operational issues or even a blackout.

Other options, while they may seem valuable, do not directly address the immediate need for stability. Increasing generation may not be appropriate if it leads to over-generation; notifying a balancing authority may delay the response; and taking units off of automatic generation control could worsen the frequency situation by further reducing system responsiveness. Hence, ensuring that generators are actively responding with their governors is the most effective and immediate action in this scenario.