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Saving Energy, Time, and Money: Even Scrooge would approve.

Which is really the cheapest: incandescent, CFL, or LED? An incandescent bulb costs less than a dollar; but other costs are involved, including power, labor, and breakage. The following chart compares the three. The LED lifespan figure is that of a popular, high quality LED bulb (higher lifespan figures usually apply to lower power or non-bulb LED’s). 25,000 hours is 8.5 years at 8 hours a day.

LED CFL Incandescent
Lifespan hours (average) 25,000 10,000 1,200
Watts per bulb 10 14 60
Cost per bulb $20 $4 $1
Kilo Watt hours (KWh) 250 350 1500
per 25,000 hours
Cost of electricity $25 $35 $150
(avg. @ $0.10/KWh)
Bulbs needed 1 3 21
Total bulb expense $20 $12 $21
______________________________________________ _____________
Total Cost over $45 $47 $171
25,000 hours

Incandescent bulbs are the clear loser. CFL and LED are so close bulb price determines the outcome. The prices used are based on advertised prices for quality brands (cheap bulbs of all three have much shorter lives) at major sellers. So, let's look at other factors.

Breakage: CFL's all have a fragile glass tube. The life span assumes no breakage. Really? Here’s a recipe: Take 1 bouncy object (ball, balloon, boy…), add 1 or more of the following: energetic kid (of any age), pet, sugar... 'nuff said. LED bulbs are robust, don’t shatter, and may well still work even if bounced by boy. How many bulbs are going to take a hit in over 8 years?

On/off cycle: Short on/off cycles diminish CFL lifespan. The Energy Star program recommends not shutting off CFL lights for less than 15 minutes. LED lights have no such limitation, a real plus for kitchen, bathroom, or lights on an occupancy sensor.

Replacement labor: Changing bulbs takes time. "Time is money," as the old saw goes. LED lights save labor, especially for difficult to reach lights.

Indirect Costs: CFL’s have a warm-up time and small amounts of mercury.

The basic costs of light bulb and energy place CFL and LED about equal. Every additional consideration puts LED lights ahead. And one more factor to consider: CFL prices have been stable for some time; LED prices drop every year, and show no sign of leveling out anytime soon. LED's are already cost effective. In the near future they will be just plain cheaper. 'Nuff said.

Contributor: Joel Zenzic
Posted By: Mary Wecker


By Mary [05/01/2014 - 00:00:00] - Add Comment

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