Calculate how much occupancy sensors will save based on your space’s actual occupancy patterns throughout the day. Select a space type to load a realistic profile, then adjust each time slot.
Please enter fixtures and wattage.
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Occupancy sensors turn lights off, or reduce them, when a space is empty, and the savings depend on how much of the time the space is really used. The calculator lets you set the occupancy for each time of day, so rarely used rooms such as storage areas, restrooms, and meeting rooms show larger savings than spaces that are in constant use.
The savings equal the power of the fixtures multiplied by the hours the lights would have been on while no one was there and by the price of electricity. Most sensors use a time delay, often around 10 to 15 minutes, before turning the lights off, which avoids switching them off on someone who is sitting still. A shorter delay saves more but can be annoying.
The type of sensor affects how well it works. Passive infrared sensors detect movement in line of sight, ultrasonic sensors detect motion around corners, and dual technology sensors combine both to reduce false triggers. A vacancy sensor requires someone to turn the light on and turns it off automatically, which saves more than an automatic on sensor. Place sensors where they have a clear view, and follow the energy code.