Boneyard Tools

LED Bulb Savings Calculator

Compare an old bulb with an LED replacement to see the energy and money you save. Enter both wattages, how many bulbs, daily hours and your rate.

How to estimate LED bulb savings

  1. Enter the old bulb wattage and the new LED wattage.
  2. Enter how many bulbs you are switching.
  3. Enter how many hours the bulbs are on each day.
  4. Enter your electricity rate per kWh to see the yearly and monthly savings.

Examples

Ten 60W bulbs replaced by 9W LEDs

60W to 9W, 10 bulbs, 5 hours/day, $0.15/kWh
510 W saved, 930.75 kWh/year, about $139.61 saved per year

Frequently asked questions

How much energy does an LED save versus an incandescent?

A 9 watt LED can replace a 60 watt incandescent, cutting about 85 percent of the power for the same brightness.

How is the yearly saving calculated?

Watts saved times hours per day times 365, divided by 1000, gives kWh saved per year. Multiply by your rate for the dollar saving.

Does this include the cost of buying the LED bulbs?

No. It shows energy savings only. Compare the yearly saving against the purchase price to estimate the payback time.

What if the LED uses more watts than the old bulb?

Then the savings come out negative, which means the swap would cost more to run. This can happen with very low wattage old bulbs.

Do LEDs really last longer?

Yes. LEDs commonly last 15,000 to 25,000 hours versus about 1,000 for incandescent, so you also replace them far less often.

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