Billing
Peak Demand
Definition
The highest instantaneous power draw (measured in kW) recorded during a billing period, typically measured over 15- or 30-minute intervals. Peak demand is the basis for demand charges on commercial utility bills.
Why It Matters for Your Business
Peak demand is the single number that drives demand charges — often the largest controllable cost on a commercial electricity bill. Managing peak demand through scheduling, automation, and storage is one of the highest-ROI energy strategies for commercial facilities.
Frequently Asked Questions
When does peak demand typically occur in commercial buildings?
Most commercial buildings peak in the afternoon (1–6 PM on weekdays) when HVAC cooling loads, lighting, and occupancy all align. Hot summer days amplify this further.
How do I find my peak demand?
Check your utility bill — there's usually a "demand" or "maximum demand" line measured in kW. Some utilities provide interval data through their online portal that shows 15-minute demand readings.