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Measure Your Light in Lumens, Not Wattage

A form of technology that you’ve used all of your life is going away. Old-style incandescent light bulbs – the technology that Thomas Edison invented more than 130 years ago – are being phased-out.


That’s happening because of the requirements mandated by the passage of the Energy Independence and Security Act (EISA) in 2007. EISA requires that all light bulbs sold and manufactured in the United States must conform to certain energy-efficiency standards. And Edison’s old invention doesn’t make the grade.

That means that you’ll no longer be able to purchase 40- and 60-watt incandescent light bulbs in 2014. Higher-wattage incandescents were phased-out during 2012 and 2013.

Lumens Are the New Watts

You’re likely accustomed to shopping for light bulbs based upon a certain wattage. The greater the wattage that a given light bulb used, the brighter the light it produced. So a 100-watt incandescent bulb would produce a much brighter light than a 40-watt incandescent. And that’s how you determined what bulb to buy. If you wanted a really bright light you purchased a high-wattage bulb. If the bulb didn’t need to be quite so bright, you purchased a low-wattage bulb.

But focusing only on wattage requirements will no longer be an effective guide to use in selecting a light bulb.

The new-style bulbs are much more energy-efficient than the old incandescents. Because of that, the amount of energy that a bulb consumes will no longer be a reliable indicator of the amount of light it produces. So instead of the wattage a bulb requires, you’ll want to focus upon the intensity of the light it produces. And light intensity is measured in lumens.

Many light bulb choices are now available to consumers, representing several styles of newer lighting technology. And all bulbs will be labeled with the amount of light that the bulb will produce, as measured in lumens. You can use the following guide as a bridge between the new and old-style technologies:

  • 40-watt incandescents produced about 450 lumens
  • 60-watt incandescents produced about 800 lumens
  • 75-watt incandescents produced about 1100 lumens
  • 100-watt incandescents produced about 1600 lumens

Watts In a Lumen?

The Natural Resources Defense Council has published a guide to the changes and new choices consumers are facing in lighting technology. And one chart in the guide clearly illustrates why wattage alone is no longer an effective measuring stick for guiding a light bulb purchase.

The replacement technologies for the old-style, standard incandescent bulbs include:

  • New halogen incandescents
  • Compact fluorescent lamps
  • Light-emitting diodes

Each is substantially more energy-efficient than standard incandescents. But each uses energy at differing rates.

For producing the equivalent brightness of a 100-watt standard incandescent bulb, for example, the new-technology bulbs range from 19 watts to 72 watts in energy consumption. But each produces the same 1600 lumens of light that a 100-watt standard incandescent would produce.

Where to Look for Lumens

Manufacturers of light bulbs are now required to supply lots of information about their products on the packaging. Look on the front of the package for a prominent disclosure about the brightness of the bulb, as measured in lumens.

Most manufacturers will also be including a smaller “lighting facts” label on the back of the packaging – similar in style to the nutrition labeling required on food products. The rated lumens will also be provided on this label, along with the estimated yearly energy costs of the bulb, expected lifespan, and other information.

Watts Are Still Important…

The wattage requirement of a bulb will continue to be an important consideration when you’re selecting a light bulb for purchase. After all, the phase-out of the old-style incandescent bulb is all about the quest for greater energy efficiency. And the wattage requirement of a bulb will continue to be a reliable indicator of the energy-efficiency it offers.

But if you want to know about the amount of light a bulb produces, forget about the wattage. From now on, the light is in the lumens.

This entry was posted on Wednesday, January 8th, 2014 at 6:00 pm. Both comments and pings are currently closed.

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