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Maximum Demand Calculation May 2026

  • The maximum of these interval demands during the billing or monitoring period is the MD.

    • | Load | Connected (kW) | Demand Factor | Contribution (kW) | |-------|----------------|---------------|-------------------| | Lighting | 4.0 | 0.8 | 3.2 | | HVAC | 6.0 | 0.8 | 4.8 | | Elevator | 7.5 | 0.6 | 4.5 | | Sockets | 10.0 | 0.3 | 3.0 | | Pumps | 4.4 | 0.7 | 3.08 | | Total MD | | | 18.58 kW |

    Install a Battery Energy Storage System programmed to discharge when the facility's load exceeds a threshold (e.g., 900 kW). The battery supplies the extra 100 kW for 15 minutes, keeping the MD at 900 kW instead of 1,000 kW.

    Who should use this method?

    Who should be cautious?

    Used when no meter exists (new installations, upgrades). maximum demand calculation

    Basic formula (per feeder or whole installation):

    [ MD = \sum (Load_i \times Diversity\ Factor_i \times Load\ Factor_i) ]

    Or more practically:

    [ MD = \textTotal Connected Load \times \textDemand Factor ] The maximum of these interval demands during the

    Where:

    Better approach – categorize loads:

    | Load Type | Typical Demand Factor (DF) | |-----------|----------------------------| | Lighting (general) | 0.7 – 0.9 | | Lighting (large area, e.g., warehouse) | 0.9 – 1.0 | | Power outlets (general use) | 0.2 – 0.5 | | Air conditioning (multiple units) | 0.6 – 0.8 | | Elevators (residential) | 0.4 – 0.6 | | Elevators (commercial) | 0.5 – 0.7 | | Pumps (continuous) | 1.0 | | Pumps (intermittent) | 0.5 – 0.7 | | Motors (single, continuous duty) | 1.0 | | Welding machines | 0.3 – 0.5 | | Kitchen equipment | 0.4 – 0.7 | | Data center IT load | 0.9 – 1.0 |

    [ MD_total = \frac\sum_i=1^n MD_individual\ feeder\ iDiversity\ Factor ] | Load | Connected (kW) | Demand Factor

    Where Diversity Factor ≥ 1.

    Example:

    Most utilities allow you to set a Contract Demand – a threshold. If you exceed it, you pay a penalty (e.g., 2× the normal rate for the excess). If your MD is consistently 10% below contract, reduce the contract to save fixed charges.