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The Business Lighting Experts

How to Pick a CFL
Once you've decided to switch, make it a pain-free process.
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Energy Efficient Bulbs

How to Pick a CFL

Here's how to make the switch:

Start with one bulb. Or Two.

For your first compact fluorescent purchase, buy just one or two bulbs to make sure that they throw the kind of light you want. Pick a lamp or ceiling fixture to start your replacement journey and evaluate the light the bulb or bulbs give before you buy replacements for your whole house. When you pick your test site, do not pick a fixture that is recessed and enclosed, on a dimmer, outside or exposed to moisture.

Evaluate your test bulbs

Do you like the light the bulbs give out? Are they bright enough and the right color? Even today, some brands of 60-watt equivalent CFLs still do not seem to give off as much light as a 60-watt incandescent bulb. You may need to replace 60-watt bulbs with two 75-watt equivalents in some ceiling fixtures to get the light you want. Or you may need to try a brighter white light. If the first bulb you use in your test site is not bright enough where you were trying it, just move it to a lesser-used closet or hall fixture and try another CFL in your test space. Also remember that some CFLs still take a minute or two to "warm up." The bulb's light may get brighter after it is on a minute or two.

Make a list

Count the number and types of bulbs in and around your home. You'll be surprised at how many light bulbs you have in your house. If you count over 70, that won't be at all unusual. You may also be surprised at the variety of bulbs. 60-watt, 100-watt, three-way, candle tip, globe and reflector. Also pay attention to the light fixtures. Clever use of reflectors, and directional lamps to get the light where you need it can save you another 50 percent energy cost and improve your comfort! Well thought out use of efficient lights can thus reduce electricity needs up to 8 times.

Replace the lights you use most often first

You'll save more money immediately that way. As long as you can use CFLs in them, start with your most used fixtures. Kitchen lights, the reading lamp by your bed, the light by the doggie door you keep on all night for Buddy — whichever switches you are hitting the most or keep on all the time are the first fixtures to target for the first bulb replacements. Make a list. Note down the wattage, size and shape of bulb you need and the type of light you might want for those areas. Then go buy a few bulbs!

Keep replacing bulbs until you have CFLs in every fixture that will take them

If you don't like a bulb in one place, try it in another! If you don't find the shape or application specific bulb you need (like for outdoor use in moist areas) on the Bulbs.com website, give us a call at (888) 455-2800 and a Bulbs.com Lighting Specialist will help.

Spend the money upfront

You have to take a deep breath, swallow hard and make a commitment to buying some of these bulbs because, for example, those 8 reflector bulbs in your kitchen track lighting may cost you $40 to replace but you know that the savings will make up for the expense very quickly. Also remember that as more people buy CFLs, prices will go down and availability of unusual bulbs will go up.

Making some lighting changes

As you replace traditional bulbs with CFLs, think about changing out enclosed fixtures that won't take CFLs and dimmer switches that take more expensive and hard- to- find dimmable CFLs. You may not want to do it now but you can plan for the future.

Tell your neighbors about your savings and trade CFL replacement tips

You may be surprised to find that they've already replaced all of their incandescent bulbs too, or that they found a bulb for that fixture you all have in your entryways.

Know your watts and lumens (light output)

We are accustomed to choosing bulbs by how much electricity they use. For example, a 40-watt incandescent bulb is on the dim side and uses less power, while a 100-watt bulb is bright and uses a lot of juice. CFL bulbs have much lower wattage numbers than their incandescent cousins, but don't let that fool you. CFLs provide much more light at a fraction of the wattage of traditional bulbs. Because of this, CFLs are often categorized by lumens. Lumens measure the amount of light a bulb gives off, making this measure a more accurate way to tell how bright the new bulbs are in comparison to the incandescent bulbs.

Incandescent CFL Lumens Cost Savings
Cost Savings
CO2 Savings (lbs)
40W 11-12W >490 $39-$44 $78-$88 507-572
60W 13-18W >900 $62-$68 $124-$136 806-884
75W 19-22W >1,200 $76-$83 $152-$166 988-1,079
100W 23-26W >1,750 $107-$112 $214-$224 1,391-1,456
150W 38-42W >2,600 $163-$169 $326-$338 2,119-2,197

Estimated calculations for cost and CO2 savings assume 15,000-hour life for CFL and represent savings over the expected life of the bulb. For exact performance specifications refer to the eSpec page for each CFL.

Bulb Fact - the rated life of a bulb is an industry calculation that measures the number of hours before 50% of the bulbs will fail. In other words, if a bulb is rated for 1,000 hours, half of the bulbs will burn out before 1,000 hours and half will last longer than 1,000 hours.

Remember this rule of thumb: CFLs use about a quarter of the wattage to produce the same light. So to replace a traditional 60-watt bulb, buy a 15-watt CFL: 60-watt incandescent / 4 = 15 watts.

Note: Some brands of 60-watt equivalent CFLs still do not seem to give off as much light as a 60watt incandescent bulb. You may need to go to two 75-watt equivalents in some ceiling fixtures to get the light you want. Or you may need to try a brighter white light. This is another reason to try buying one or two CFLs first. If the first bulb you buy is not bright enough where you were trying it, just move it to a lesser-used closet or laundry room and try another CFL in your test site. Again, comparing the lumen output of your old bulb (if you still have an original package) to the lumen output of the CFL you plan to purchase should help you to avoid purchasing an inadequate bulb.

What Color of Light do you need? Selecting the proper color is an important decision

Light from yesterday's fluorescent lights, common in offices and schools, can seem "cold." Light from CFLs is different and better - CFLs can achieve the same kind of lighting you're used to from incandescent bulbs. Look for packages labeled "2700 degrees Kelvin" or "warm-white." If you seek a brighter, "whiter" light there are CFLs with 5000 degree Kelvin or "bright white" color temperature. In between the 2700K and 5000K bulbs you may find 4100K or "cool white" bulbs, a little whiter than the warm white 2700K and a little more yellow than the bright white 5000K. 4100K is the color temperature typically used in commercial offices and production areas.

Get the right bulb shape and size

First, some CFLs are larger than their incandescent equivalents causing the CFL to be too big for some lamps. Depending on where you're going to install your CFL be sure you determine the size of the fixture enclosure or the shade (to know how big a bulb it can accommodate) and whether or not the bulb will show. Shades that rest directly on the bulb with a metal clip won't work well on the spiral bulb. Many CFLs have a coiled bulb and the coils can be either large or compact. Check to see which will fit in your light fixture before you buy. The good news is that there may be a CFL with a shape very similar to the old style bulb you are replacing. These newer CFLs are available on our website.

Second, most CFLs screw into standard light sockets; however, on some bulbs, the plastic piece above the screw part (the ballast) is slightly wider and might not fit in every lamp. Caution: Avoid the bases that terminate with pins. They are for commercial applications and will not fit into the sockets in your home.

Buy the right bulb for the right application

Buy a CFL Globe to replace the globe lights in your bathroom. Don't put 40-watt equivalent swirls in a wall sconce that takes candle tip or candelabra bulb; they'll look silly and you (or someone else who lives in the house) won't be happy with them. Also, make sure you like the shape and look of the replacement CFL. The candelabra bulb replacements in CFL look more like a torpedo. As CFLs become more popular you can be sure that the bulbs you want will be on the market. You may have to do a little research to find the right bulb. If you can't find them at your local store, go online. Or, in the future, you may want to consider replacing older fixtures with more modern fixtures that will accept CFLs.

Buy ENERGY STAR® for reliability

Bulbs that carry the ENERGY STAR label have met or exceeded a long list of tests for energy efficiency and reliability. ENERGY STAR is a joint government program of the U.S. Environmental Protection Agency and the U.S. Department of Energy. Keep in mind that not all types of CFLs are tested by ENERGY STAR so purchasing any non-ENERGY STAR bulbs should be done through a reputable supplier like Bulbs.com to insure support after your purchase. For a list of qualified ENERGY STAR products and suppliers, visit www.energystar.gov.

Be careful choosing CFLs for a dimmer

There are exceptions to this rule, but the majority of CFLs are not made for dimmers yet. There are a few that already do work, but scrutinize the package to make sure. Look for products that include statements saying "for use with dimmers." Again, consider purchasing just one or two to be sure they work on the dimmers in your home or business. Even dimmable CFLs that work on your dimmer will not dim the same way that an incandescent or halogen bulb will. The dimming range for a CFL usually goes from 100% (full power) down to 20%. Below 20% power the bulb shuts off completely making the effective dimming range of the CFL just 80% of the range of a comparable incandescent or halogen. Evaluate how much you use each dimmer switch. Some people find they have dimmers on many switches in their home and they don't really use most of the dimmers. You may want to simply replace the dimmer switch with a regular switch and use regular CFLs. Bulbs.com carries a selection of CFLs that work on dimmers.

Do not use CFLs in recessed and enclosed fixtures

Recessed light fixtures and fixtures that are completely enclosed (no air flow) are more likely to cause early failure for most CFLs. Why? The additional heat generated by the bulb in the enclosed fixture is too much for the ballast that is integrated into the base of the bulb. Although the CFL will operate in these fixtures, the life of the bulb will be shortened substantially from its rated life.

Check for outdoor use

Many, not all, CFLs are designed for both indoor and outdoor use. Check the packaging to make sure you get the kind you need. Use CFLs labeled for use in outdoor fixtures only. CFLs will not work well in temperatures below 20 degrees Fahrenheit. If you intend to use the bulbs in an environment below 20 degrees check with the distributor or manufacturer to be sure the bulbs you buy will do the job. Don't use a CFL in a socket or fixture that is exposed to the elements unless the bulb is made for outdoor use. For exterior fixtures like the "jelly jar" type near the door, a standard spiral CFL will work but likely won't last too long because of the enclosed nature of the jelly jar globe. Find a CFL intended for use in an enclosed fixture for the jelly jars. For outdoor floodlight fixtures with halogen lamps, there are a few CFL PAR bulbs now on the market with wattage and lumen output equivalent to a 90 watt or 100-watt halogen PAR. These PAR CFLs are also rated for outdoor use. Again, testing one or two is the best option to insure they deliver the quality of light you require. If a CFL is not a suitable replacement for your halogen flood then consider using a motion detector. Motion detectors save energy and money by turning on lights only when needed.

Dispose of your bulbs properly

All compact fluorescents contain trace amounts of mercury. But don't worry. First of all, there is far less mercury in CFLs than in other items knocking about the house: CFLs (4 mg), thermometers (500 mg), older thermostats (3,000 mg). Plus, using CFLs actually prevent mercury from being released into the air thanks to their huge energy savings. A power plant, for instance, emits about 10 mg of mercury to produce the electricity to run an incandescent bulb compared to only 2.4 mg of mercury to run a CFL for the same amount of time. Recycling burnt-out CFLs is the best option.

Contact Bulbs.com to evaluate the energy savings available for your business

If you like the energy savings from CFLs in your home, you'll love them at your business or homeowner's association. Whether your workplace is a retail store, office, restaurant, hotel, production facility, warehouse or other commercial building, the energy saving technology used to create CFLs is being deployed in many other types of lighting as well. Retailers and hotel chains across the nation have converted incandescent and halogen bulbs to CFLs. As you might expect, the annual energy savings in a commercial facility that converts to energy efficient lighting is measured in the thousands (if not tens of thousands) of dollars. For you business owners and managers, consider contacting Bulbs.com to assist you with energy saving calculations as well as to determine if your electric utility is offering a rebate incentive for the installation of energy efficient lighting, heating and air conditioning systems.

Portions of this material were obtained from the following:

  1. Greenpeace
  2. www.fightglobalwarming.com
  3. Chesapeake Climate Action Network
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