Light Me Up

We have all read the light fixture warning not to use anything higher than a 60-watt bulb, or 75, etc. The newer LED bulbs still fall under that fixture rating, however since the equivalent LED bulbs use much less wattage, you can choose a watt equivalency that is higher than that of the old bulbs. As an example, a 60 watt bulb equivalent is a 9 watt LED. They both put out 800 lumens.


You can replace an old 60 watt bulb with a 100-watt equivalent LED bulb (or higher), which is about 17 watts and therefore well under the safety limit of a 60-watt maximum fixture. You get lower energy bills and almost twice the light. One limiting factor might be bulb size, so be sure to check the physical size of new bulbs to make sure they fit the socket. Every now and then I come up with a bright idea.

Buying Light Bulbs

We typically have been buying light bulbs based on how much energy they consume (Watts), regardless of light emitted (Lumens). All that began to change with the advent of different types of light bulbs, such as CFL, halogen, LED, etc., since they consume different amounts of energy to produce the same amount of light.

Lumens measure how much light you are getting from a bulb, regardless of type and regardless of energy consumed. This equalizes all bulbs and types for comparison. More lumens means brighter light.

Another measurement that is not well understood is Kelvin. It is a scale of measurement for the color a light produces. The higher the Kelvin (K) number, the cooler the light appears. Most bulbs will be in the 2,500K to 6,500K range, with 2,500 being the warmest and 6,500 the coolest. Kelvin is usually ignored except for specific lighting circumstances. The 2,700K to 3,000K range is warm and inviting, 3,500K casts a neutral light, 4,100K casts a cool and bright light, 5,500K to 6,500K range is closest to daylight.

To compare brightness of typical old style bulbs, here are a few examples:
Replace a 100-watt incandescent bulb with a bulb that gives you about 1600 lumens,
Replace a 75W bulb with a bulb that gives you about 1100 lumens,
Replace a 60W bulb with a bulb that gives you about 800 lumens,
Replace a 40W bulb with a bulb that gives you about 450 lumens.

Sixty watt bulbs used to be the standard as they offered the best compromise of minimum required light and cheaper cost. Now that energy cost has been so greatly reduced, 1100 lumen lights are becoming the standard minimum. Brighter lights make it easier to see and make everything look better, especially when trying to sell your house.

LED, Lumen, CFL, and CRI

We are now faced with many choices for light bulbs. Prices vary widely for not much difference in light. Here a few things to know about the choices.

First, lumens are the new watts. Watts are power and lumens are light. An old incandescent 60 watts is about 800 lumens of light. The wattage does not matter and most of the comparisons regarding electricity costs are measured over years, so not very consequential in a monthly or annual budget. A 60W incandescent lamp may push 800 lumens, while a CFL only needs 15W and an LED only needs 10W to produce the same lumens. (A 10W incandescent is a night light.) The thing to remember is how bright you want your light to be. Look at lumens below to get the correct amount of light from your new bulbs.

incandescent bulb
watts - lumens
60 - 800
75 - 1,100
100 - 1,600
150 - 2,600

Heat might not seem important, but with a number of lights burning, it adds up, especially during the summer. One heat test - halogen bulb, a type of incandescent bulb, measured 327 degrees. A Cree LED downlight was measured 107 degrees and a Philips Par38 CFL measured 167 degrees. LEDs produce 3.4 btu's/hour, compared to 85 for incandescent bulbs.

Bugs don't fly toward many LEDs, because bugs are attracted to ultraviolet light and most LEDs do not give off this type of light.

LED are rated to last 50,000 hours, while CFLs are rated for 10,000 hours and incandescents are rated for about 1,000 hours.

LED bulbs turn on as quickly as incandescent bulbs and faster than CFLs. LEDs produce roughly the same amount of useful light, but much of that light is focused in one direction. LEDs typically shine up, rather than in all directions like incandescent bulbs. Newer LEDs can be omnidirectional, look for that word on the package.

Some LEDs do not dim well and tend to buzz or sputter when the dimming is at half. Check the package to make sure the bulb will work with a dimmer.

A new term to further confuse us is CRI, because of the number of different light types. It did not make any difference in the past as all lights were the same. CRI is color rendering index. The higher the CRI, the better the color rendering ability. Light sources with a CRI of 90 or higher are excellent at color rendering and should be used for tasks requiring the most accurate color discrimination. CRI is independent of color temperature, but I won't even go there. Too much information.

When considering lighting, I usually think of CFL as meaning 'crap for light'. They take longer to turn on (it typically takes 30 seconds to 3 minutes to complete), need more energy to turn on, contain mercury, may leak UV radiation, do not work well in cold conditions, produce artificial fluorescent color, and are less efficient than LEDs.

Although initial price is still much higher, the price of LEDs is coming down quickly. LEDs are down to $4.97 at Home Depot, a far cry from the old $20 they used to cost. Bottom Line, let your old bulbs burn out before you rush out to buy new "energy savers" the price will likely be cheaper when you are ready to replace. Also, higher lumens are brighter and higher CRI provides better color discrimination.