Sometimes small changes really do add up to a big difference.
The shift by American consumers to energy-efficient light bulbs over the past few years has contributed directly to a decline in overall electricity use, according to a new analysis by the Energy Institute at the Haas School of Business at the University of California Berkeley.
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After more than 60 years of rising about 4 percent a year, electricity use per capita fell in nearly every state from 2010 to 2015.
Energy-efficient light bulbs, including both LEDs and compact fluorescent bulbs, now comprise 80 percent of all U.S. lighting sales, and Professor Lucas Davis estimates that there are a billion energy efficient bulbs now installed in U.S. homes. If used three hours a day, those bulbs could easily account for an energy savings of 50 million megawatts a year, or 0.16 megawatt hours per capita, roughly the decrease shown by the data.
What’s not clear in the data is whether we’ve now passed peak Americans electricity usage, or if usage will creep back up. The lower cost of lighting may spur some consumers to increase their usage, and an eventual shift to electric vehicles would also lead to higher per capita electricity usage rates. “The recent decrease is historic and significant, but over the long run it would be a mistake to bet against our ability to consumer more energy,” David writes.