Maximum Demand Calculator May 2026

In the world of electrical engineering and facility management, Maximum Demand (MD) is a critical metric. It isn't just about keeping the lights on; it directly impacts your capital expenditure (cable/transformer sizing) and operational expenditure (electricity bills).

Grab your last 12 utility bills. Find the highest "Demand" value. Compare it to the sum of your connected load. You will likely find you are paying for capacity you rarely use. maximum demand calculator

Why average? A motor starting up might draw 600A for 2 seconds, but that doesn't melt the cables. The 15-minute average is what heats the transformer. Why does it matter? Utilities size their transformers for your MD. If you have a 5-minute spike once a month, you are paying for infrastructure you use 0.01% of the time. You cannot simply add up the nameplate ratings of all breakers. That is Connected Load , not Maximum Demand. Diversity saves you. In the world of electrical engineering and facility

Write down every load’s nominal power. Find the highest "Demand" value