LED Energy Savings Calculator
Calculate annual energy and cost savings from switching to LED lighting, including CO2 reduction and payback period.
Results
What is it?
LED (Light Emitting Diode) bulbs use 75-80% less energy than incandescent bulbs for the same light output. A 9W LED replaces a 60W incandescent (saving 51W per bulb). LEDs also last 15,000-25,000 hours vs. 1,000 hours for incandescents, reducing replacement frequency and waste. The CO2 factor used (0.386 kg/kWh) is the US EPA average grid emissions factor.
How to use
1. Enter the number of bulbs you want to replace. 2. Enter the wattage of your old bulbs (60W incandescent is most common). 3. Enter the wattage of the replacement LED (9-10W for a 60W equivalent). 4. Enter average daily hours of use per bulb. 5. Enter your electricity rate per kWh.
Example scenario
Replacing 20 x 60W incandescents with 9W LEDs. Watt savings = (60-9) x 20 = 1,020W = 1.02 kW. At 5 hours/day: annual savings = 1.02 x 5 x 365 = 1,862 kWh. At $0.15/kWh: savings = $279/year. CO2 avoided = 1,862 x 0.386 = 719 kg/year. With LEDs at $8 each: payback = (20 x $8) / $279 x 12 = 6.9 months.
Pro tip
LEDs also save on cooling costs — incandescent bulbs convert 90% of energy to heat. In air-conditioned spaces, this heat must be removed by the AC, adding a secondary energy cost. The real savings in warm climates can be 10-15% higher than the electricity savings alone suggest.