Now that you’ve replaced every bulb in your home with those twisty compact fluorescents, you can relax for a while, right? They last 10 years, so by the time you have to change another bulb, you’ll be ready to replace them with LEDs. Not so fast, says California utility PG&E, which insists that CFLs don’t last nearly as long as claimed. But our brighter brethren at Consumer Reports state that some of them really do, and they’ve got test results to prove it.

Consumer Reports flips the switch on the debate:

The Wall Street Journal reports that in California, compact fluorescent lightbulbs aren’t lasting as long as expected. Utilities like PG&E, which has subsidized consumer purchases of CFLs in the state, originally figured a bulb would last more than nine years, but based on experience has lowered that to about six. We’ve found in our past tests that some spiral CFLs were still shining brightly after 10,300 hours of use. That works out to 3 hours a day for 9.4 years.

Our latest CFL tests found that after cycling on (for 3 hours) and off (for 20 minutes) since early 2009, or 6,000 hours, brightness and warm-up times remained virtually the same as after 3,000 hours of testing. An outside lab has confirmed our result.

While PG&E may be bemoaning the miscalculation, our experts say that you’ll save money even if a CFL lasts 6,000 hours rather than the 10,000 the manufacturer claims. A typical incandescent lasts about 1,000 hours and costs 50 cents. You’d need six bulbs and spend about $42 on bulbs and electricity. Or you can buy one CFL and spend $12, electricity included.

Consumer Reports does point out that CFLs aren’t right for every lighting need, and also recommends that you keep your receipt when purchasing bulbs, just in case they really do cut out a few years early.

California utility says CFLs burning out faster than expected [Consumer Reports]

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