Earth Matters by Jacqueline Milner – the 411 on CFL’s (Compact Fluorescent Bulbs)

CFN– One of our Earth Matters’ followers sent a note asking if we could supply information about light bulbs as he wasn’t convinced that switching from Incandescent Light Bulbs to Compact Fluorescent Bulbs (CFL’s) was the best choice for his pocket book or the environment.  In writing this article we at Earth Matters hope to provide information which will help you in formulating a clear course of action based on your needs and wants.Firstly, the life span of a CFL is on average ten times that of an incandescent bulb.  Now the CFL’s average about four times the cost of an incandescent bulb however considering the proposed length of service the higher cost of the bulb is definitely offset assuming all other things such energy consumption are equal.

CFL’s consume considerable less power which produces huge savings for your wallet and translates into a lighter carbon footprint in producing the product.

According to using a compact fluorescent bulb can save about $42.00 in total costs over the lifetime of the bulb and reduce greenhouse gas produced by power plants by about 690 pounds of carbon dioxide.  According to the U.S. Energy Star program the CFL will pay for itself in about six months time.

Each CFL contains a small amount of toxic mercury.  Absorbing or inhaling mercury has been attributed to causing brain damage in adults and children.  Breaking a CFL in your home or disposing of your used CFL’s in the garbage unleashes poison into your environment.  The following link gives clean-up instructions should a CFL be broken in your home.

All burnt out bulbs can be disposed of in your hazardous waste recycling days in your community or may be returned to your local Hardware store who will (if they offer the service, check before taking) look after disposing of this products safely.  I phoned two of our local Hardware Stores, Canadian Tire and Rona; both offered safe, FREE disposal of CFL’s.  Inquire in your community.  Many vendors of CFL’s offer disposal of CFL’s for the benefit of their clients and community.  Please do take advantage of this service for the benefit of our living planet.

Now one might think that an incandescent bulb offers a better alternative because it does not contain this toxic mercury however further investigation proves otherwise.  While the incandescent bulb does not contain mercury it does have a higher overall mercury footprint when compared to the CFL.  This is due to the additional energy required to use the bulb over the same time frame.
This energy is often supplied by coal-fired power plants which are our number one source of mercury pollution according to  Consider that the exposure to mercury from a CFL will take place only if the glass that contains the mercury breaks.  So your potential for risk is determined by the amount of times that you have every broken a light bulb.Some words for thought.  According to only 5% of consumers use CFL bulbs.  Surprising given the bulb is widely available.  According to Energy Star, as noted on the Earth Friends site, “The United States could eliminate greenhouse gas emissions equal to 800,000 cars if each household in the country replace just one incandescent bulb with a CFL bulb.”

According to using CFL’s are one of the easiest ways to shrink your electricity bill and help the environment.

Earth Matters encourages and always welcomes your commentary below or to


  1. I have heard reports that the life span of CFL lights are exaggerated especially if you turn the lights on and off frequently. They will last the advertised length of time if you never turn them off.

  2. CFLs unfortunately do contain a small amount of mercury, but disposing of them properly eliminates this hazard. As Jacqueline points out, the electricity savings (and therefore the reduced amount of mercury pollution from coal fired power plants) more than make up for the mercury in the bulb.

    As for turning lights on and off all the time, yes, this will reduce their lifespan, regardless of the type of bulb. However, we have a CFL in a bathroom that gets turned off and on frequently. After almost 5 years, we have only just had to change it.

    For more information on CFLs, go to:

  3. F.Y.I. Mr. Coffey…Some of the material that I read mentioned that turning on and off the lights frequently can affect the life of the bulb, no precise details were given. I have an area in my studio which is lit with a CFL and that light is turned on and off several times a day. The age of the last bulb that I replaced in this area was about 5 years old. Also keep in mind that as per information mentioned above “a CFL bulb pays for itself in 6 months”. In fact almost every bulb in my household uses a CFL. Lights are turned on and off on entering and leaving the living spaces. They have already been in service for several years.

  4. I’m curious to know what percentage of the power consumed in eastern Ontario is produced by coal-fired generators.

  5. I did manage to find the 2006 figures to answer Ed’s question:
    Nuclear: 36.6%
    Hydro Electric: 24.9%
    Coal: 20.6%
    Oil/Gas: 16.4%
    Wind: 1.3%
    Other: 0.2%

    Note, these are 2006 figures, from before the onset of the Green Energy Act. Since the act, the proportion of coal derived electricity has dropped, whereas that from wind, biomass, solar etc. has increased somewhat.

    This is the situation in Ontario. Quebec is mostly Hydro, with some nuclear, NB has some nuclear, Alberta is mostly coal and gas.

    CFL’s greatest pollution controlling abilities are in places like Alberta, where the electricity is from fossil fuels. However, in a relatively clean place like Ontario, they are still worthwhile, as they reduce the overall load on the system, and thus costs.

  6. Those figures probably haven’t changed significantly since 2006. I’m wondering more about the local power supply. My thinking is that if your home is being supplied by a non coal-fired generator, the mercury emission/disposal equation changes quite a bit. I think Richard is correct about dirty Alberta power and relatively clean Ontario power.

  7. Hi Ed,

    As to the local power supply, if you live in Cornwall, your power actually comes from Hydro Quebec. Ontario as a whole, however, gets its power from the Ontario Grid, which crisscrosses the province like a spider web. The major inputs are the three nuclear stations, as well as major installations like Niagara Falls.

    Although I understand electronics well, I am not a grid engineer, so I will happily accept correction. To put it very simply, once power enters the grid, it blends in with the rest of the power already there. It’s rather like tributaries to a river entering and making the river larger.

    When you turn on a light, what you get is basically a blend of power from all its sources. Roughly 35% of your light comes from nuclear, 25% from hydro, etc. In the same way, the water the Cornwall Water Treatment plant takes out of the river is a mixture of everything that has been added throughout the great lakes and from Kingston downstream. As a result, some small fraction of Cornwall’s water supply actually came from, for example, a sewer serving Toronto City Hall. Unfortunately, there is no way to filter out this contribution, any more than it is possible to filter out the individual electrons that come from a coal fired generating plant.

    Hope this helps.

  8. Thanks Richard. I too have an electrical engineering background, but have never been involved with power generation or distribution on a large scale. If indeed we are all being powered by a “homogenized” source, and with the staggering decline of manufacturing in Ontario over the last ten or so years, you’d think that those coal-fired generators would be getting used a lot less these days.

  9. How close are we to cost effective LED residential lighting? No where near the heat (standard bulb has a bit more than CFL) or electricity consumption and the possibility of various fixture sizes & shapes are increased.

    I assume CFL’s were created to use less electricity until LED’s came on line, unfortunatly, they are only made in China and India.

  10. In comparison to incandescent bulbs, fluorescent lamps and CFLs are the better option. CFLs emit approximately the same amount of visible light as incandescents, but they last 8 to 15 times as long and provide significant energy savings. The use of more efficient lighting options, such as CFLs, is one of easiest and lowest-cost ways for the nation to reduce electricity use and greenhouse gases. However, these lamps are fragile and, upon breaking, they release mercury vapor that can be detrimental to handlers’ health—from those involved with handling new bulbs to people involved with storing, packaging and shipping used lamps.
    Mercury-containing lamps need to be recycled properly. Fluorescent lamps should be taken to a recycling center or placed in one of a variety of containers that are marketed for transportation of fluorescent lamps and CFLs, however, many don’t provide sufficient protection against mercury vapor emitted from broken lamps. Using a proven packaging design is vital to ensuring the safety of people who handle these lamps, as well as maintaining their green benefits. Read about a recent study that tested several packaging configurations here:

  11. Hi Brad. I’m still concerned that CFLs provide a limited spectrum of light as opposed to the incandescents that provide full spectrum light. I have CfLs everywhere in my house where we don’t spend much time because the quality of light doesn’t matter. Also, especially at this time of year, the incandescent lamps help heat our homes with great efficiency. Are you by chance a VaporLok™ rep?

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