Occupancy Sensor Savings

Estimate the lighting energy, demand, maintenance, cost, and emissions savings from adding occupancy sensors, including simple payback and IRR. Results update as you type.

Inputs

Rates & utility

Electricity cost

$/kWh

Demand cost

$/kW-mo

Labor rate

$/h

Carbon intensity

lb-CO₂/kWh

Peak demand reduction?

Operating schedule

Operating hours

h/day

Operating days

days/wk

Operating weeks

wk/yr

Occupancy method

Time occupied

Fixtures & lamps

Number of fixtures

Ballast factor

Bulbs per fixture

Bulb wattage

Bulb life

Bulb replace time

Bulb cost

Sensors

Fixtures controlled

Fixtures per sensor

Sensor install time

Sensor cost

Finance

Energy escalation

%/yr

IRR calculation period

Results

Current operating hours2,040 h/yr

Proposed operating hours1,020 h/yr

Total connected power24.08 kW

Electricity savings24,562 kWh/yr

Demand savings0.00 kW

Electricity cost savings2,556.86 $/yr

Demand cost savings0.00 $/yr

Maintenance (material) savings276.46 $/yr

Maintenance (labor) savings43.66 $/yr

CO₂ emission savings11.653 t/yr

Total cost savings2,876.99 $/yr

Total implementation cost3,498.32 $

Simple payback14.6 months

Internal rate of return77.58 %

Cash flow over 5 years

Annual cash flowCumulative savings

Savings come from the reduction between current and occupied operating hours applied to the connected lighting load, plus avoided lamp-replacement material and labor. Defaults reflect a typical assessment; adjust to your facility.