What price freedom?

More investigation of what it costs to preserve my freedom to choose incandescent light bulbs.

A spreadsheet prepared by Productdose.com compares the costs of burning three different kinds of bulbs: the CFL, the incandescent, and the LED. You can download it here and plug in your own electric bills, kilowatt rate, and type of bulbs in your home.

Let’s give it a try.

The average home is said to use 1,500 kwh per month. We’ll cut it to 1,000 per month at about 11 cents per kilowatt hour, for a total of about $110 a month.

Here are the numbers, based on 20 light bulbs in the home and an estimated daily usage of an hour.

  Incandescent CFL LED
Life span (hours) 1,500 10,000 60,000
Watts 60 14 6
KWh over 60k hours 3,600 840 360
Electricity cost $396 $92.40 $39.60
Bulbs needed for 60,000 hours 40 6 1
Equivalent 60k bulb expense $53.80 $17.88 $54.95
Total 60,000 lighting spending $449.80 $110.28 $94.55
Household cost $8,996 $2,205.60 $1,891
Savings over incandescent 0 $6,790.40 $7,105
KWh used per month 36 8 4
Electricity cost (11 cents kwh) $3.96 $.92 $.40
Savings by switching 0 $3.04 $3.56
KWh per year 438 102 44
Electricity cost (11 cents kwh) $48.18 $11.24 $4.82
Savings by switching $0 $36.94 $43.36

At $36.94 yearly savings, I could pay off the new gas tax on 738 gallons of gasoline. I fill up about every 8 days with 12 gallons of gas (Chevy Cavalier). So I use about 550 gallons of gasoline in a year. I could pay the tax on the gas and still have $9.40 left over to put toward the increased excise tax.

  • It’s worth $37 a year for me to have light that I can read by. I tried the CFLs and simply don’t like them. I’m keeping an open mind on LEDs – they’ll get their chance to shine, so to speak.

  • Bob Collins

    I have a three-way CFL in one of my lamps. Early in the morning it works out great. When I get up, it’s usually dark. I stumble around turning off as many lights as possible that my wife — who gets up even earlier — turned on as my eyes pound. I open the door, grab the paper, fumble for the coffee and turn on the light.

    Because it’s CFL, it doesn’t have much power when I turn it on; it takes about 4 minutes to work its way up to proper brightness… just enough to ease my old eyes into the light.

    One thing I have noticed, those claims on the packaging, like “lasts 7 years” are total baloney.

  • ryan

    @Daveg: Have you tried CFL’s lately? they have made quite an improvement over what they once were. I have CFLs in every socket in my house and I can read by them just fine. There are different types that have different light outputs. Try a few out at the store before you buy to make sure you have the right light style.

  • bsimon

    I’ve noticed the outside (CFL) lights take a while to warm up to full brightness, but I don’t have that problem with the inside lights. The big disadvantage for me is their lack of dimmability. For the lights on a dimmer switch, I’m slowly migrating to halogen (marginal energy savings; superior longevity). For non-dimmable lights, CFLs are slowly replacing incandescent as the incandescent burn out. Another complicating factor is that certain fixtures are difficult to fit with CFLs, or were designed for exposed incandescent bulbs for aesthetic reasons. I’d like to go LED, but still find it cost-prohibitive when standing in the store, even though I know they’ll pay for themselves in savings over time.

  • paule

    Interesting chart, Bob.

    The problem with CFL and LED bulbs is that they usually do contain mercury. I was shocked to realize this, since I have’t noticed warnings or disposal recommendations on the packaging.

    Here is a company that manufactures mercury-free LED bulbs:


  • Bob Collins

    An estimated 5 milligrams of mercury, according to the EPA is in a CFL. The instructions do say to dispose of it properly and don’t throw it in the trash. BTW, your computer monitor has mercury in it, too