Are all genereators serve energy for consumers throughout the year?

The number of generators connected in parallel serve the energy for consumers.According season(or time),the load varies.In winter,half of the load will be eliminated.At this half of load ,the running of all generators is uneconomical.So,optimum condition should be obtained.This will be achieved by eliminating unnecessary generators from bus-bar(or load) during that period.Frequent connection and disconnection of generators should must be done in-order to achieve optimum operation.