In a scenario where reactive reserves still exist, what should a System Operator initially do to manage decreasing voltage?

When managing decreasing voltage in a power system where reactive reserves are still available, placing capacitor banks in service is a very effective initial response. Capacitor banks are specifically designed to provide reactive power (VARs), which helps increase voltage levels. By adding these capacitors into the circuit, the system can compensate for reactive power deficiencies, thereby stabilizing the voltage and improving the overall performance of the electrical network.

Utilizing generators to absorb VARs is a valid consideration, but it can be more complex and may require additional coordination with the generators themselves. Furthermore, increasing system load generally exacerbates voltage issues and is counterproductive in this scenario. De-energizing lightly loaded lines may also not address the immediate need for voltage support, and it could lead to further complications in the system operation.

In summary, placing capacitor banks into service quickly addresses the issue of low voltage by providing necessary reactive support to stabilize the system.