Since CFL light bulbs began attracting widespread popularity, one number that I've heard is that a good rule of thumb for the average lifespan of a CFL bulb would be approximately seven years.
I'm here to attest to the fact that this certainly seems to be true!
We moved into our home in 2007, and one of the first things I did was start replacing many lights around the house with CFL bulbs, from table lamps to as many overhead fixtures as we could, many of which I discovered had burned out bulbs anyway.
It's now 2015, just over 7.5 years since we moved in, and over the last 6-9 months, I've noticed a huge spike in the burn out of CFL bulbs. Every 2-3 weeks, it seems, a bulb has burned out.
CFL Bulbs as a Standard: Then And Now
In 2007, CFL bulbs were still pretty expensive compared to traditional incandescent bulbs. Fast forward to 2015, and the CFL bulbs have become much cheaper, and the incandescent bulbs are not even available anymore!
Back when we first started putting in CFL bulbs, they were $2-3 per bulb, a lot higher if you needed things like bulbs that went in recessed cans or three-way bulbs for table laps. We purchased all of these types of bulbs. I've since learned that we really don't need 3-way bulbs in our lamps, as we used just one setting 99.9% of the time anyways, and that a regular CFL bulb with a bit higher wattage seemed to work just great in our recessed cans. This has lowered the cost.
On top of that, the current price of a standard 60-watt replacement is now just $0.71. Our energy company subsidizes the cost, and a 4-pack is available for just over $2.80 from the nearby Home Depot.
Two things that seems to have stabilized is light quality and brightness. When we first started buying bulbs, the standard seemed to have a more bluish-white hue, rather than the soft white standard, which seemed harder to find. Earlier adaptations of CFL bulbs also noted a pretty significant time to reach full brightness. Both of these have since made tremendous strides in terms of what I've observed.
What About LED Bulbs?
Since 2007, the new player on the block has emerged with LED bulbs now traditionally available. They boast an even longer span (3-times that of a CFL bulb, by advertised accounts), and also use even less energy (about one-fourth of a traditional incandescent bulb, and roughly one-half of a CFL bulb), but are still very pricey. A standard 60-watt replacement bulb can cost around $8.
The cost analysis tells me that that an $8 bulb would compare to roughly three $0.70 bulbs over the same lifetime, with the CFL bulbs coming out $5.90 ahead. The expected cost savings, well, it's hard to determine that over a 20+ year time frame, but I'm guessing it would likely be a wash.
We have two LED bulbs in our house. We have two table lamps that held the aforementioned three-way CFL bulbs, one of which burned out. I wanted to replace both lamps with identical bulbs to give an even look, and at the time, our energy company was subsidizing LED bulbs which were suitable, so I picked up two of them for less than $5 apiece.
At that price, I was more than happy to try them out,and so far they seem to put out great light and last well.
CFL or LED: What Will It Be?
So, the question is, should we start using LED bulbs or continue using LED bulbs? My current strategy is to continue using CFL bulbs, at least at the current prices. My reasoning is that the prices will likely continue to decline on LED bulbs during the current life cycle of CFL bulbs, so when it's seven years from now, and I'm on another round, at that point the LED technology will likely be the standard, and will be even cheaper than it is now.
This will also give me a chance to make sure that the LED bulbs do, in fact, last longer, at least past the seven year time frame. If one or both of the bulbs in our lamp burns out in the next seven years, then it would stand to reason that the longevity may need to be more closely examined. Since, at least so much of the current price value, is dependent on the bulbs lasting for years, decades even, rather than months, the quality has to be top-notch.
Readers, what type of bulbs are you using in your house? CFL, LED, or are you still old-school, and working off a stockpile of incandescent bulbs?