Compact fluorescent light bulbs are promoted as revolutionary power-saving devices—able to produce more light with less juice and last for nearly 10 years. But a review of conservation measures undertaken by California—a state that adopted CFLs more enthusiastically than any other—shows the bulbs to be a little disappointing, reports the Wall Street Journal. CFLs were supposed to last 9.4 years, according to initial projections by California's PG&E, but that's now been revised to 6.3 years.
The bulbs burn out even faster in locations such as bathrooms and in recessed lighting, or when they're turned on and off frequently. They're still more efficient than the soon-to-be-gone incandescent bulbs, but considering that California utilities are shelling out $548 million over seven years to subsidize consumer purchases, the less-than-hoped-for results take a toll. "What California has learned, in a nutshell, is that it is hard to accurately predict and tricky to measure energy savings," writes the Journal.