I moved into a newly-built house in April of 2006, so as of the time I'm writing this, I've been here about three and a half years. For the first year or so in my house, I wasn't really paying too much attention to my energy usage and thus, for example, all of my light bulbs were incandescent bulbs (the kind we have used for over a century). I had been aware of electricity usage issues all my life, so it had already been ingrained into my psyche to do things like turn off lights and appliances when not in use, and I've always done this as long as I can remember.
Of course the past few years have really brought energy consumption to the forefront of our national attention, and as such plenty of articles and news stories have focused on what we as consumers can do to reduce our energy usage. Many of the stories suggested purchasing and using "compact fluorescent" light bulbs as a quick and easy way to immediately reduce electricity usage. Compact fluorescents bulbs are fluorescent, but they work in "regular" light bulb sockets.
I didn't investigate these new bulbs too much other than to note that the packaging would indicate that the bulbs would cast as much light as incandescent bulbs, but would only use about a quarter of the electricity.
So over the course of a couple years I heeded the advice of these stories and, I gradually replaced many of the incandescent light bulbs in my home. I started with the bulbs I used most frequently, the main floor lamp in my living room, my bed's night light, and the bulbs in my garage. Over time, I'd pick up various sizes and styles of CF bulbs whenever I visited discount stores like Sam's Club or Walmart. As of September 2009, I have replaced 27 of the 47 light bulbs in my home with CF bulbs.
My electricity provider in Wyoming is Rocky Mountain Power. One of the features of their billing procedure is that they track your average daily electricity usage, and over time they give you a graph of this data for the previous 13 months. I recently collected enough of my bills with these graphs on them so that I could plot the past three and a half years (40 months), and I came up with this graph of my average daily electricity usage:
It doesn't take a math whiz to look at this graph and see a trend toward lower usage. At the beginning of my time in my house, I would average 12 or 13 Kilowatt hours of electricity usage with an occasional month of 14. But recently my daily averages have dropped to 10 or 11 Kwh's.
In fact, what I did is I averaged my daily usage over the first 12 months living in my house and compared that to the past 12 months. What I found is that for the first 12 months my average daily Kwh usage was 12.83 Kwh's, and for the most recent 12 months (September 2008 through August 2009), I have averaged 10.58 Kwh's of electricity usage per day. That's a difference of 2.25 Kwh's per day, or a reduction of about 17.5%. In real dollars, this adds up to a savings of between $32.00 to $81.00 per year depending on how you calculate the price of a Kwh. I have very likely already paid for all the CF light bulbs I have purchased over the past couple years, and this is an annual savings I will continue to enjoy as long as I continue to use CF light bulbs.
One important question to ask is whether or not the decrease in average daily Kwh usage is due exclusively to replacing incandescent bulbs with CF's, or whether there might be another explanation. The answer to this is that as far as I can remember, my electricity usage is about the same today as it was 3.5 years ago in terms of my major appliances (have not replaced any). So my conclusion is that the savings I have achieved can be attributed almost exclusively to replacing incandescent bulbs with CF's.
Not everything about Compact Fluorescent Light Bulbs is perfect. In fact, here are a few items that are on the negative side of using CF's:
- When you first turn on a CF bulb, some light comes on immediately, but not 100% of the light capacity of the bulb. In fact, depending mostly on the temperature of the surrounding air, a CF can take up to 2 minutes to light to its full capacity. At first this is rather distracting, but you get used to it over time.
- During the first few seconds of operation, a CF bulb uses MORE electricity than a standard incandescent bulb. In fact, according to the television program Mythbusters, it takes about 23 seconds for a CF bulb to match the electrical usage of an incandescent. Therefore, for example, if you were to measure the electricity used in a CF versus an incandescent bulb such that you turned on both bulbs simultaneously for 10 seconds, then turned them off for a minute and kept repeating the procedure over and over, the CF bulb would very likely end up using more electricity in the long run. However, this example is extreme and one that you are not likely to encounter during everyday human usage.
- CF's contain a small amount of mercury (I've heard about 5 milligrams). Therefore you need to be more careful not to break them and release the mercury into the environment. If you do break one and the detritus ends up all over your house you may need to have an expensive mercury cleanup done. (I broke a CF bulb once, but it was entirely contained in a light fixture so I did no cleanup.) And, because of the mercury, burned out or broken CF bulbs should be taken to a recycling center, not dumped in the garbage.
