Demand Factor = Maximum demand of a system / Total connected load on the system
Demand factor is always less than one.
Demand Factor is always change with the time to time or hours to hours of use and it will not constant.
The connected load is always known so it will be easy to calculate the maximum demand if the demand factor for a certain supply is known at different time intervals and seasons.
The lower the demand factor, the less system capacity required to serve the connected load.