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Lightbulb Efficiency Comparison Chart

Buying a light bulb for your home or business used to be a simple task. Most bulbs were incandescent, so all you had to do was find the desired wattage and then buy it. Today there are so many light bulb options for your home or your business that deciding which bulb to purchase is no longer straightforward.

The chart below compares some of the major characteristics of common bulb types.

Lightbulb efficiency comparison chart

Lightbulb Efficiency Comparison Chart

Lumens per Watt: Where Efficiency Lives in Bulbs

Lumens per Watt shows how efficient a bulb is at converting power into light. At 10 lumens per watt, a 100 watt bulb is not very efficient. The energy lost is converted into heat, which is why incandescent bulbs are much hotter to the touch than CFL or LED bulbs.

The efficiency of CFL bulbs in converting energy into light falls between that of incandescent and LED bulbs. As LED bulbs continue to improve, CFL bulbs will likely be phased out.

For homeowners, LED bulbs are the most efficient bulbs at converting energy into light. LEDs aren’t always a ‘slam dunk’ though – for commercial buildings, 4’ 0” t-8 fluorescent tubes are more efficient than LED bulbs.

LEDs For the Win

The last three rows in the chart show the important differences between bulbs. Incandescent, florescent, and CFL bulbs don’t have the same lifespan as LED bulbs, so you’ll have to purchase additional bulbs as the old ones burn out. Those extra bulbs cost money. To get 25,000 hours of use from 60-watt incandescent bulbs, you’ll have to spend $12.50 in bulbs, more than the cost of one LED.

The Cost to Operate number provides the best approximation of the total value of the bulb. LED bulbs win this comparison hands-down. Despite the high up-front costs of LED bulbs, their low cost of operation and long lifespan mean that they are a much better investment than incandescent, fluorescent, or halogen bulbs.

For more information on selecting an LED bulb, view this infographic developed by ENERGY STAR.

DEFINITIONS:

Lumens: measures the “brightness”, or the amount of light produced by the bulb

Watts: the amount of power consumed by the bulb

Lifespan: measures the typical life of the bulb.

Price per bulb: an approximation based on a recent market survey, and we averaged the prices to round numbers to make the comparisons easier.