How do you calculate KVA demand?

KVA demand is most effectively calculated by observing power demand within a system over the course of a year, notes the Electrical Contractor website. If these statistics are not available, then estimated total demand must be used in place of yearly demand until statistics can be accrued.

Total demand is the full need for power expressed within a system when all of its components are active. The ampacity of a given system is not always sufficient to meet total demand, notes Electrical Contractor.

Total demand statistics are acquired by watching system performance during a 15-minute timeframe. This gives assessors a rough idea of the system's demands and its capacity to handle new loads.