So, Watt’s Up With Light Bulbs These Days?
There have been a lot of changes in the light bulb industry in the past few years.
1. The standard, old-fashioned, incandescent 100 Watt light bulb is phased out in 2011. As of January 1,
2011, no more 100 Watt Incandescent light bulbs can be manufactured or shipped to the store for sale.
Stores can continue to sell existing stocks of 100 watt incandescent light bulbs.
2. As of January 1, 2012, the same thing happened to 75 watt incandescent light bulbs.
3. As of January 1, 2013, the same thing will happen to 60 and 40 watt incandescent light bulbs.
This is a result of the Energy Independence and Security Act (EISA) that was signed in 2007 by former
President George W. Bush. This is one way the US is trying to reduce the number of new power plants that
need to be built. Our population is growing and conservation is the cheapest and easiest way for the U.S. to
ensure that everyone has enough power.
So what’s a consumer to do???
Here are some pros and cons about different light bulbs. I have also included two tables that detail the cost for
each type of light bulb.
Old-Fashioned Incandescent Pros:
1.
2.
3.
4.
5.
They are what people are accustomed to.
They are instantly on and instantly bright.
They are cheap to produce and cheap to buy
They are dimmable with traditional dimmers.
They have good color rendering index.
Old-Fashioned Incandescent Cons:
1. They have a short life span.
2. They produce a lot of heat because 90% of the energy used goes to producing heat and 10% goes to
producing light.
3. They use more energy per lumen. This costs more money in the long run.
Halogen Incandescent Pros:
1.
2.
3.
4.
5.
They are instantly on and instantly bright.
They have a good color rendering index.
They are dimmable with traditional dimmers.
They use less energy than old-fashioned incandescent light bulbs.
They last longer than old-fashioned incandescent light bulbs.
Halogen Incandescent Cons:
1. They are much more expensive than old-fashioned incandescent light bulbs.
2. They produce A LOT of heat. In fact, some Universities have banned halogen incandescent lights
because they have caused fires.
3. They do not save as much energy as the CFL or LED light bulbs and don’t last as long either.
CFL (Compact Fluorescent Lights, the twisty lights) Pros:
1.
2.
3.
4.
5.
6.
7.
They produce light in a different way so 75% of energy goes to producing light. This saves energy.
They produce less heat.
They are much less expensive than they use to be.
They are easy to find in stores in a variety of color temperatures.
They last longer than old-fashioned incandescent light bulbs.
They are currently the most cost-effective lighting solution for most people.
If the brand purchased has an Energy Star label, they come with a minimum two –year warranty. Save
the receipt and proof of purchase. If they burn out too soon, you can send them back to the
manufacturer for a new light bulb.
CFL Cons:
1. They do take a while to achieve full light. However, newer light bulbs are MUCH faster and must come
on within 1 second and get fully bright in 3 minutes to meet Energy Star guidelines.
2. Their life span is shortened by rapidly turning them on and off. Therefore, they might not be
appropriate for motion sensor lights or other places where you don’t use the light a lot but turn them on
frequently like closets or hallways.
3. They do not have as great a color rendering index as either old-fashioned incandescent or halogen
incandescent light bulbs.
4. They have a very small amount of mercury vapor. Mercury is a poison and although there is no evidence
of people becoming poisoned by the mercury in CFLs, recycling them is difficult and expensive so most
people throw them away adding to landfill toxins.
LED (Light Emitting Diode) Pros:
1. They will last a phenomenally long time. Twenty-seven to 50 years.
2. They are very energy efficient.
3. They are coming down in price and are becoming easier to find at box stores like Lowes and Home
Depot.
4. They contain no mercury so they can be thrown into the garbage safely.
5. LEDs are tough and so they can handle rougher handling.
6. Their life span isn’t shortened by being turned on and off frequently.
LED Cons:
1. They are still expensive compared to other bulbs so people have a hard time justifying the up-front cost
of LED light bulbs.
2. They have a very high color temperature so even the ones that say “Warm White” are really bright.
Approximate
Lumens
Produced
1600
Old-Fashioned
Incandescent Light
Bulb Wattage,
Life Span = 10002000 hours
100
Initial cost +
Lifetime
Energy Cost =
Total Cost *
Cost per
Year if used
3 hours per
day **
0.50 + 10.50
= $11.00
0.50 + 7.87 =
$8.37
0.25 + 6.30 =
$6.55
0.25 + 4.20 =
$4.45
$12.05
Halogen
Incandescent
Wattage, Life
Span = 40008000 hours
72
$8.62
53
$7.17
43
$4.87
29
Initial cost +
Lifetime
Energy Cost =
Total Cost *
Cost per
Year if used
3 hours per
day**
1.86 + 31.50
= $33.36
1.82 + 22.26
= $24.08
2.49 + 18.06
= $20.55
2.99 + 12.18
= $15.17
$9.13
1100
75
800
60
430
40
Approximate
Lumens
Produced
CFL Wattage, Life
Span = 10,000
hours
Initial cost +
Lifetime
Energy Cost =
Total Cost *
Cost per
Year if used
3 hours per
day **
LED Wattage,
Life Span =
30,000 –
50,000 hours
Initial cost +
Lifetime
Energy Cost =
Total Cost *
Cost per
Year if
used 3
hours per
day **
$4.29
1600
23-28
$2.93
20
1100
18-23
$2.38
14-18
800
12-15
$1.49
11-14
430
9-11
2.65 + 24.15
= $26.80
2.87 + 18.90
= $21.77
0.99 + 12.60
= $13.59
1.74 + 9.45 =
$11.19
$1.22
6.5-8
54.64 + 63.00
= $117.64
37.98 + 44.10
= $82.08
11.49 + 34.65
= $46.14
9.97 + 20.48
= $30.45
$6.59
$5.63
$4.15
$3.00
$1.68
$1.11
* Choose the lowest life span and lowest wattage to predict the Lifetime Energy Cost. The cost is calculated for
PGE customers. To get MWL costs approximations, multiply the lifetime cost by 0.60 or 60%. Research was done
to find the lowest price for the light bulb in question from Lowes, Home Depot, and 1000Bulbs.com. The
equation for Lifetime Energy Cost looks like this: (Lowest Light Bulb Wattage) x (Smallest Life Span) ÷ 1000 X
(0.105). In this case, 0.105 is the cost per kWh for PGE.
** The Cost per Year is calculated using the Total Cost and dividing by the total life span. In the case of the OldFashioned Incandescent Lights, this means that the bulb actually had to be replaced in less than one year.
New Light Bulb Labels
Using the new light bulb labels can help you buy the bulb that works the best for you. The new labeling
requirements have lumens (the amount of light each bulb produces) right at the top. The Estimated Yearly
Energy Cost is easy to find. However, the label ONLY estimates the cost for energy and doesn’t add the cost of
the bulb as calculated in the above tables.
In PGE territory the average cost per kWh is 10.5 cents so the 11 cent approximation is pretty close. MWL
charges about 6 cents per kWh by the time you add the monthly $11.60 Customer Charge into the calculations.
So if you divide the yearly energy cost by 2 you will closely approximate your cost if you are a MWL customer.
Here are some examples of Light Bulb Labels.
Notice they also tell you if the bulb is Energy Star rated and the approximate life span of the bulb.
The label also tells consumers the about the light appearance. Old-fashioned incandescent light bulbs had a
yellow color-temperature which equaled 2700 K. Newer CFL and LED lights can have a yellow 2700 K color
temperature or they can have a higher color-temperature at 4100 K or more. These bulbs will appear whiter
and brighter.
Also, notice that the label tells you if the light bulb contains mercury and tells you where to find more
information on how to clean up light bulbs that contain mercury and how to dispose them.
Finally, the watts (which is how we formerly figured out how bright a light bulb was) is listed at the bottom of
the label.