Lighting Control Calculator

Lighting power density check per ASHRAE 90.1 with dimming zone, sensor, and control device counts.

Floor area (sq ft)

Building type (1-10)

Installed lighting (W)

Lighting zones

Daylight zones

Tab to move between fields

Code LPD limit (W/sq ft)

0.82

Actual LPD (W/sq ft)0.82

Max allowed watts8,200

Occupancy sensors8

Daylight sensors3

Control relays8

Contactor panels1

Est. annual savings (kWh)9,379

Est. annual savings ($)$1,125

Code CompliantYes

Lpd Margin (%)0%

Time Clocks1

How to Use This Calculator

Enter the total floor area in square feet and select the building type (1–10) to look up the ASHRAE 90.1 LPD limit.
Enter installed lighting wattage if known, or leave at 0 to use the code maximum for budgeting.
Enter the number of separately controlled lighting zones and the number of daylight zones with windows or skylights.
Read the ASHRAE 90.1 LPD limit (W/sq ft), maximum allowed watts, and whether your design is code compliant.
Use the occupancy sensor, daylight sensor, and control relay counts to size your lighting control system.
Review the estimated annual energy savings in kWh and dollars from controls.

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