LED Savings Calculator
Calculate how much energy and money you will save per year by converting your existing lighting to LED, and how many months the investment takes to pay back.
How is it calculated?
Annual consumption (kWh) = number of luminaires × luminaire wattage (W) × daily operating hours × days per year ÷ 1000. The difference between the existing and the LED system multiplied by the electricity price gives the annual savings. If a control system is selected, its typical additional saving is deducted from the LED consumption.
To choose the right LED wattage, you need the luminaire that delivers the same illuminance; this is what a lighting design is for. For more on watts and efficacy, see our article What is a watt and how is it calculated?.
Frequently asked questions
How much can be saved by switching to LED?
Savings depend on the type of the old luminaire. Switching from fluorescent to LED typically halves energy consumption; from metal halide and halogen it falls by 60–85%. Adding sensors and dimming increases savings further.
Which formula is used?
Annual consumption (kWh) = number of luminaires × luminaire wattage (W) × daily operating hours × days per year ÷ 1000. Annual cost = annual consumption × electricity unit price. On the LED side, control system savings are deducted from consumption.
How is the payback period calculated?
The total investment you enter for the LED conversion is divided by the annual monetary savings and converted to months.
Are the results exact?
No, they are a preliminary estimate. Actual savings depend on the datasheet values of the luminaires, the lighting calculation of the space and usage habits. A lighting design is recommended for exact values.