The developments in lighting in the past few years have been significant. Changes and improvements appear frequently so it is appropriate to review the criteria that you can use when choosing a new bulb or light fixture.
A walk down the bulb aisle at your favourite hardware or building supply store can be confusing, so I am going to use this column to sort out some of the criteria you might use to select an appropriate replacement bulb. Just remember, although the newer bulbs will provide a good dose of sticker shock, the cheaper bulbs using new technology may not deliver on the promises written on the carton. The following comments are general, but assume that we are talking about bulbs that screw into a standard socket and are not subject to frequent on-off cycles which affect longevity, especially of fluorescent bulbs. Also remember that some fluorescent bulbs take time to warm up before they reach their full output. Look for an “instant-on” rating if that is a concern.
A word about the abbreviations and acronyms you will encounter. LED stands for Light Emitting Diode; CFL stands for Compact Fluorescent (usually meaning a spiral tube by itself or contained in a glass shell so it looks like an incandescent bulb). Another thing you have to be careful about is that most CFLs are not dimmable, while most LEDs and halogen bulbs can be connected to a dimmable circuit. Check the label or ask the store clerk if you need dimmable bulbs.
The first thing you may want to consider after you have absorbed the cost is what colour of light you are willing to accept. Colour in lighting is measured in Kelvins. Bulbs for domestic use range from 1800 to about 6000 degrees Kelvin. 1800 K represents the warm orange light of a candle while the cool colour of the noon sun is about 5600 K. Bulbs marked “daylight” are usually around 5000 K. The normal incandescent light that we have been accustomed to buying is rated at about 2700 K. “Cool white” fluorescents are probably in the range of 4100 to 4500 K.
Many people have been concerned about the shift away from incandescent bulbs because when they look in a mirror they appear better, more healthy, when the light is in the range of 2500 to 3000 K. A great deal of effort is going into devising efficient bulbs in that colour range.
The second consideration is the amount of light produced by a bulb. The light output is measured in lumens, a 40 watt incandescent bulb produces about 490 lumens; 60 watts = 860 lumens and 100 watts = 1620 lumens. By comparison, an 8 watt LED produces about 470 lumens, almost as much as the 40 watt incandescent using five times the amount of power.
The third point is longevity. Most bulbs are rated in hours of useful life. Incandescent bulbs are rated from 1,000 to 2,000 hours or 1 to 2 years of use at 3 hours per day. CFLs may last 5 to 10 years while LEDs can be expected to last 20 years or more. That is why a $25 LED will save the owner over $125 in energy and replacement costs over the lifetime of the bulb compared to a 50 cent incandescent. It also means that you should look for warranties on the packaging. Some LED bulbs have a 5-year warranty. Could you find the invoice 5 years down the road?
A final reminder: All fluorescent bulbs, compact or tube type, contain mercury. At the end of their life they should not be put in the garbage or recycled. Put them in the hazardous waste system of your building or take them to a drop-off centre such as the City’s Solid Waste Depot at 400 Commissioners Street in the Portlands. (Tuesday to Friday 10 to 6 and Saturday 7 to noon) Almost all incandescent halogen and LED bulbs go in the regular garbage.