How to Buy a Better Lightbulb

The U.S. is phasing out energy-hog lightbulbs in January. How do the alternatives stack up?

Join Our Community of Science Lovers!

Contrary to rumor, the incandescent lightbulb is not going away—at least not right away. New U.S. regulations, starting January 1, cap energy consumption of a roughly 1,600-lumen bulb (equivalent to a standard 100-watt incandescent bulb) at 72 watts—which means the workhorse of home lighting will have to become about 30 percent more efficient overnight. The law will expand in the next two years to cover 75-, 60- and 40-watt bulbs. There is room for improvement: incandescent bulbs currently waste 90 percent of their energy as heat. Halogen incandescents provide a more efficient, if pricier, alternative and will give compact fluorescents a run for their money. A light-emitting-diode replacement for 100-watt bulbs is expected to reach market this year; dimmer LEDs are already available. Consumers will be able to check federally mandated labels that give performance specs, similar to nutrition labels on food, but here we illuminate the essential facts.

On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.

Graphic by George Retseck and Jen Christiansen Sources: U.S. Department of Energy and Efficacy calculations based on currently available bulbs (traditional, halogen and compact fluorescent); SWITCH LIGHTING (led)

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American