If an extreme situation was to
persist and public appeals were unsuccessful, it could be necessary to
disconnect some customers. If load is extraordinarily high or generating units
are off line, the system would automatically disconnect customers to avoid
system instability, widespread blackouts and system damage. Depending on where
problems occur, different areas would be disconnected.
During such an emergency, utilities
might not be able to keep power on at essential facilities such as hospitals,
sewage treatment plants, airports and specific sections of large cities with
networked circuits. The utilities would restore power to these essential
facilities as quickly as possible, if necessary by disconnecting other areas as
part of controlled rolling blackouts.