For Gary Lewis and the Playboys, it was a piece of jewelry that stopped glistening when they sang "this diamond ring doesn't shine for me anymore" in the 1960s.
For the general public in 2014, it's LED lightbulbs that are going dark. In a test by consumer watchdog Which?
, nearly 30 percent of bulbs burned out ages before manufacturers claimed they would.
That's not good news for an industry where the selling pitch often includes "it will last you a lifetime."
I'm a fan of LED bulbs, but as I've often written, we can't yet prove that they last for the eons that vendors claim, because none of us have owned and operated one for more than a few years yet.
Typically, manufacturers tout "15 years", "17 years" or "25 years." I've even heard "50 years" and "for your lifetime." The number seems to vary with the mood of the maker, but wherever it falls in that span, it's alluringly longer than the year or two after which your old incandescent bulb would go pop.
But dream on. U.K.-based Which? sampled bulbs from retailers across Europe and reported:
We tested 230 bulbs in total, and 66 of those failed before the 10,000 hour mark, despite all of them claiming a lifespan of at least 15,000 hours.
Some of the flops didn't even last 6,000 hours, which is the minimum lifespan that the European Union will allow under a mandate taking hold on March 1.
In case you're wondering how many years 15,000 hours is in light bulb time: It's probably somewhere between 10 and 15. When I wrote about this three years ago, I focused on "25,000 hour" claims, and pointed out that manufacturers were translating that number as
15 years in some cases, and as 17 and 25 years
I like the Which? test. It was not a computer simulation. Which? actually put the bulbs through their paces, switching them on for nearly 3 hours at a time, off for 15 minutes, and then on again.
The good news is that over 70 percent of the bulbs did not expire early. The 230 included 5 units each of 46 different models.
There's a lesson here: LED bulbs come in different qualities, and that quality can vary by vendor. For example, of the products tested from U.K. retail shelves, only models from Ikea and U.S.-based manufacturer TCP flunked; they were among the sub-6000 hour performers. Which? noted:
Ikea said the bulb had passed its own tests and those in a third-party lab. It is looking into why the bulb failed our test and has removed it from sale in countries where it was still available. TCP said it was already aware of the problem with this bulb, which is why it withdrew it from sale. TCP added that it no longer deals with the supplier of that bulb and now makes its LED bulbs in-house.
Perhaps it's a matter of you get what you pay for. A quick check of online LED bulb prices shows them ranging from around £5 to £17 (roughly $8 to $28) across different wattages.
LED bulbs include electronics that can go wrong
. The light source - the light emitting diode - is often not the problem; rather, the circuits that convert voltage from alternating current to direct current can fail, as can those that knock down voltage levels.
More good news: Nobody seems to dispute the energy saving aspect of LED bulbs, which require only about 20 percent of the electricity of conventional incandescents. That saves on environmentally damaging CO2 emissions, and it reduces our utility bills.
As long as the hardware price keeps falling - not long ago it hovered around $50, staggering for consumers accustomed to a buck-a-bulb incandescents - and once quality and reliability stabilizes, then consumers and the industry alike could be singing a shining LED song.