Bulb Size -- Standard incandescent bulbs (A lamps) are 2.37" in diameter and 4.43" long, including the screw-in base.  Many CFLs are larger than this, except non-dimmables in lower wattages.  In certain applications it may not matter, like many shaded lamps, but it can make a difference in any fixtures that have short shades or are fully enclosed with little clearance.  Parabolic lamps for use in recessed cans or track lighting may also be significantly longer than standard.  If there is some room for adjustment in the can, they may still work, but places with little clearance may not have great options yet.  The size is often not listed on the packaging, so if it will make a difference, you should bring a tape measure or ruler to the store.  Alternately, you can shop at a site like http://www.buylighting.com where you can check the specifications for diameter and M.O.L or Maximum Outside Length.

Functionality -- When you start looking at the range of lights and fixtures in your house, you may find there are more considerations to keep in mind, such as needing bulbs that can go in fan lights, in dimmer controlled locations, in enclosed (or more critically enclosed and recessed) fixtures or outdoors.  A few years ago, there were no lights that would meet these needs and many are not yet available in local stores, but they are on the market and can be obtained online.  One exception is that dimmers manufactured before 1990 are not compatible with any type of CFL.  Such switches can be replaced fairly inexpensively or even changed to a toggle switch (an option my husband urges me, the dimmer fanatic, to include).  Local Action is also thinking about facilitating group buying of such items for better prices (please contact us at info@LocalActionPA.org if you would be interested in such an arrangement).  These lights are different because they can withstand vibration or have different ballasts or are less heat sensitive or have ballasts (the fat base) that function below 60 degrees.

Further questions often range to asking whether the lights work the same.  They do pause a beat after the switch is flicked before going on, but there is not the long, flickering delay that you may remember from years past.  Even though they switch on nearly instantly though, they still do take time to warm up fully and reach their full brightness.  As a result they may not be the best choice in locations that get turned on occasionally and for brief periods.

Is there a flicker?  Low cost bulbs may still exhibit some perceptible flicker, but most do not.  Some dimmable bulbs may start to flicker at lower light levels.  Some individuals are more sensitive to this than others.  Particularly if you are in this category, it is wise to go slow when you start out and make sure that you like the bulb you've chosen before investing in 10 of them.

The package says that the product includes Mercury (Hg) and is therefore hazardous waste and must be disposed of according to local regulations.  For home owners in PA this means they can be put in the trash.  Whether that is a good idea remains to be seen, but it certainly isn't a lot of red tape.  The general argument has been made that if your electricity comes from coal-fired plants, the mercury emissions from the additional energy needed to get the same amount of light out of incandescents are equal or greater to the content in the CFL replacement bulbs.  If you start with cleaner power, however, this is not the case.  There are also concerns for the health and safety of workers exposed to the mercury from disposal.  As the market for CFLs grows, as it is certain to, now that some countries, like Australia, are starting to ban the sale of incandescents, these issues will be addressed as there will be more call and profit in recycling and buy-back programs.  For now, we can depend on the long life of the bulbs (estimated at anywhere from 6 to 15 years) to give us some breathing room on having to deal with the consequences of throwing them out.


Selected brand reviews:


We happen to have tried out a range of brands for some of the harder-to-fit applications, particularly dimmers, and have the following comments on the products tried:

Phillips -- these are long, rectangular bulbs which perform fine and dim well, but at 6" long they may not be suitable for many existing fixtures; in addition, in some applications, particularly as wall-washers, they seem to exhibit some minor flicker; they are inexpensive, for dimmables, about $9, depending on wattage.

GreenLight -- this brand has a great deal of market penetration and visibility on the web, on Amazon, etc; they are also 6" long, though mini-coil shaped, and may not fit many fixtures; in addition, their transformers buzz noticeably; they run around $12 to $15.

TCP Spring Lamp -- this brand is by far the smallest dimmable light, though still bigger than the standard A lamp; it has no flicker or buzz and has a very wide range of functional dimmability (before it just goes dark); it does have low color temperature options for cozy home use; it is the most expensive at around $17.

 

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