kVA = (kW × Demand Factor × Growth Factor) / PF Select next standard size above calculated kVA
100kW load, PF=0.85, 80% demand, 20% growth: kVA = (100×0.8×1.2)/0.85 = 113 kVA Select standard 160 kVA transformer
Frequently Asked Questions
Demand factor is the ratio of maximum demand to total connected load. A building with 100kW of connected equipment rarely uses all of it simultaneously. Typical values: 60–80% for commercial, 50–70% for industrial.
Standard distribution transformer ratings: 25, 50, 100, 160, 250, 315, 400, 500, 630, 800, 1000 kVA and above. Always select the next size up from the calculated requirement.