The value of capacitor automation was demonstrated at Kansas City Power & Light (KCPL), Kansas City, Missouri, U.S., in the summer of 1999. On Feb. 17, 1999, KCPL experienced a boiler explosion at its Hawthorn generating station, taking the plant out of service. This caused concern because Hawthorn 5 is the only KCPL base-load generating station within the metropolitan area. The unit would be out of commission over the next two summer peak periods. On July 27, 1999, transmission dispatchers requested to turn on all available distribution capacitors to support system VAR and voltage issues. KCPL used a newly developed automation query tool to identify more than 160 open capacitors. Many of these capacitors would have turned on later in the day as the load increased. However, capacitor automation allowed KCPL to switch these capacitors on and proactively supply needed VAR support before the peak loading period.

The distribution automation engineer switched capacitors using a global command to change the control strategy of these capacitors from their normal "VAR/voltage" or "temperature/voltage" strategy to a new strategy of "preferred position of capacitor switch closed with voltage override protection." As a result, KCPL satisfied the service-quality needs of its customers while addressing the immediate operating criteria of its system. Before capacitor automation, KCPL would have been unable to meet this request in this time frame. Later in the summer when the load decreased, another global command was issued through the radio system to remotely change the control strategy back to the normal "VAR/voltage" or "temperature/voltage" mode. The system power factor during the KCPL 1999 summer peak with all available capacitors switched in was 99.99 percent, the highest power factor ever recorded at KCPL.

Currently, KCPL has more than 680 automated distribution capacitors in service. These controls comprise a combination of VAR controls and heat controls, all with voltage override capabilities. The voltage sensing for these controls is from A-phase, which is what normally regulates the substation's load-tap changer. The automated capacitor control system is made possible by using a CellNet Data Systems wireless communications system, EnergyLine Systems capacitor controls and WinMon graphical user interface, and LiveData Software servers. The combination of these products provides KCPL with the features and flexibility needed to control capacitor banks, view real time and historical data, create reports and give users throughout KCPL's corporate network access to the data from their PCs.