Interpreting Light Bulb Labels

Interpreting Light Bulb Labels

In passing the Energy Independence and Security Act of 2007 (EISA) Congress mandated strict new energy standards.  These standards affected many energy guzzling industries.  One of the requirements, to help the consumer with all the new technology, is that light bulbs must have labels, like food labels. Our focus for this article will be light bulbs and how to read the label so you can purchase the correct bulb for your purpose.

Over the decade since this bill was passed bulbs have greatly improved. The bulbs use less energy and last longer.  In fact, changing the five, yes only 5, most used light fixtures in your abode could save you up to $75 per year.  Since the average home has between 40 and 65 light fixtures, that could be great savings.  But the savings will only be realized if you choose the correct bulb.  The question then is how do I choose the correct bulb.

Initially the bulb must meet the needs of the task at hand.  Recently I was at a workshop in another city.  After a long day on workshop, we had homework.  The lamps in the hotel room were only for ambiance, even the one on the desk!  I had every light in the room on and still had to use the light from my phone to get enough light to complete the assignment!  That definitely was not comfortable.

Once again, how do I choose the correct bulb?  To help us hapless consumers inundated with a rapidly changing world, bulbs have labels similar to food labels.  Now the questions is how do I read the label?  What do all the new terms mean?

In the past we use to shop bulbs by watts, which was how much energy they used.  The old incandescent bulbs used lots of energy.  About 90% of it was turned into heat.  The more watts, the bright the light and more heat given off by the bulb.


Lumen is the measure of the brightness of a bulb. In the past the brightness was determined by the energy used, or watts.  In other words, the brighter the bulb, the higher the watts and the more energy was used.  A 100 watt bulb used 40 more watts than the 60 watt bulb.  With new technology that isn’t necessarily the case.  Different technologies are able to produce an equal amount of brightness, lumens, using less energy. The chart below helps compare traditional Watts to Lumens.

As you can see the wattage and lumens differ depending on the type of light bulb you purchase.

Estimated Yearly Energy Cost: This is pretty straightforward, but you should look at the values used to calculate the cost (3 hours a day and 11 cents per kWh) and change them for your circumstances to get an accurate number for you. Despite your specific values, this is a good comparison tool to see which light bulb at the same lumens costs the least to operate.

Looking at the two labels above shows the vast difference between bulbs. The bulb on the left saves you $5.66 each year.  Putting the bulb on the left into your 5 most used light fixtures saves you $28.80. The average home has 47 electric bulb sockets.  If a home owner switched all their bulbs from incandescent bulbs to CFLs they could save $266. Other articles quote higher savings.

The areas most often overlooked when changing bulbs are

  • Outdoors: Porch lights and motion activated security lights can give great energy savings when changed to an energy saving lamp. Make sure the product you purchase is rated for use with switching devices.
  • Torchiere Lamps: Consider replacing double ended halogen fixtures with lamps that use a traditional screw base.
  • Closets: Using CFL bulbs in closets can aid in matching clothing colors because they provide higher color rendering and make sorting of blacks and dark blues easier.
  • Garage: Because CFL’s have higher color temperatures such as daylight, this makes it easier to perform tasks in traditionally poorly lit areas. Don’t forget the bulb inside the garage door opener.
  • Laundry Room: Using fluorescent or compacts in this area makes better use of task lighting for pre-treating clothing and sorting of stained items.
  • Refrigerator: Though this light doesn’t stay on long, LED bulbs may save up to $30.00 and keep food fresher.
  • Hallways: Though many people do not use them often, replacing bulbs in this area comes in handy when you need them.
  • Bathrooms: newer compact fluorescent lamps do not have long warm up times as older lamps. Using them in this area can drastically reduce electricity while providing better quality of light for tasks such as makeup and grooming

Life: Based on using a bulb for three hours a day, this number will give you the bulb’s life expectancy. Lifespan can be affected in many ways. For example, CFLs don’t perform as long when they are exposed to extreme temperatures, moisture or movement or if they are turned on and off repeatedly for short periods.  Different types of bulbs last different lengths of time.  LEDs tend to last the longest. The longer lasting bulbs tend to cost more initially, but may yield bigger savings in the long run.

Light Appearance: The color of the light emitted by the bulb is listed in Kelvins. Incandescent bulbs give off a warm, soft light we are familiar with and fall in the 2,700-3,000K range. Bulbs of this color are best for relaxed settings, such as the family room or bedroom. The 3,500-4,100K range gives off a bright, cool white light best for the kitchen and office, and the 5,000-6,500K range gives off light that best imitates bluish daylight, which is good for reading or task lighting.

Energy Used: This number will be listed in watts – and the lower the number the less energy it uses. You may be used to buying 75 watt bulbs for your home, but now the average watt bulb you bring home may be closer to 20 watts! The chart below illustrates the energy usage for the four types of bulbs at different energy levels.

There we have the terminology.  That is enough information to digest in one article.  We will look at different bulb labels in the next article.



References: to read-a-light-bulb-label/.