Photo by p. Gordon/Creative Commons license, Flickr

Efficient Light Bulb Study Generates Heated Debate

ByBrian Handwerk
May 03, 2013
8 min read

When we published a story this week on a study that showed the negative consequences of environmental messaging on light bulbs, we suspected the subject would spark a lively debate—and our readers delivered.

The post garnered more than 2,500 Facebook “likes,” 582 tweets, 93 Google+ “+1s,” and more than 90 comments.

A few themes are worth highlighting:

“It’s Not the Labels. It’s the Light!”

A number of readers insisted it wasn’t the wording on the packaging, but the quality of the bulb that makes new lighting choices a turnoff. As much as I absolutely love being conservative when it comes to my resource consumption because of the savings, I absolutely prefer standard light bulbs for one reason and one reason only . . . Lighting,” said commenter Robert Henry. “The lighting with high-efficiency/energy-saving bulbs is just WAY too intense for me. I always prefer natural light if I have a choice and Fluorescent and LED bulbs just don’t provide the diffused lighting that incandescent bulbs do. Needless to say, I haven’t used incandescent bulbs for 4 years regardless, but I miss them, despite the savings I get with the energy-efficient option.

Our colleague, Brian Howard, one of the editors of National Geographic News, who has written a book on energy-efficient lighting, has offered some helpful advice for consumers who are concerned with CFL light quality: “This person should be using halogens, or “halogen hybrid” bulbs, which have the same warm light as incandescents but are more efficient,” Howard says. “It’s also true that the highest quality CFL and LED bulbs are getting very close to incandescents. Always buy Energy Star-certified CFLs, which must meet minimum performance standards for light output, startup time, and quality. If you want warmer light get warm light CFLs, not bright white. Also use shades that diffuse the light and soften it. Indirect lighting also helps with this a lot.” (Related Quiz: “What You Don’t Know About Efficient Lighting“)

Incandescent light bulbs, as designed by Thomas Edison, literally put out more heat than light, and some folks have come to rely on that feature. “It’s nice to have a few of the old style filament bulbs around to keep things in my unheated shed from freezing on those few really cold nights,” wrote aRocket Scientist.

It’s worth noting that this is an inefficient way to heat; this reader may want to try a space heater instead.

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Meredith Heffernan added praise for the warm glow: “For me, they keep my headaches at bayI am very sensitive to daylight, but less efficient yellow lights don’t bother me as much. If a law were passed saying we couldn’t use these any more, it would basically be because the government wants to be more eco-friendly at the expense of others, when really it is a moral choice from person-to-person.

Other readers complained about how many of the efficient compact fluorescent (CFL) bulbs are incompatible with dimmers (true), and how some have annoying time delays before they begin to burn at full strength. Jonathan Magnus notes the risk of broken bones from stumbling around in the dark while the light heats up: “A hospital trip will put a lot more carbon into the air than a single incandescent bulb.

No doubt the light quality may be a reason that some people—no matter what their political persuasion—would prefer to avoid CFLs. But the remarkable finding of the study by Wharton School of the University of Pennsylvania and Duke University’s Fuqua School of Business was that if CFL light quality really was the decisive factor, it must have rankled conservatives more than liberals because of the clear political divide in consumer behavior.

“We’re Not Mercurial. We Don’t Like Mercury!”

A number of readers said they rejected energy-efficient bulbs because of environmental concerns about the toxic metal, mercury, found in every CFL. “Just because something is labeled “Green” doesn’t mean [they’re] good for the environment and may actually be worse,” says Lets It right. CFLs “are filled with hazardous materials both for the humans and for environment. If an incandescent breaks use a broom and sweep it up. If a CFL’s breaks your better break out the hazardous material suit breather and all.”

In fact, while you won’t need a hazmat suit, the EPA has rather detailed instructions on how to properly handle a broken bulb and avoid unnecessary exposure—especially to infants, children, and pregnant women. It’s not possible to entirely rule out adverse health impacts from exposure to any amount of mercury. But most problems are caused by larger or chronic exposures. A typical CFL bulb contains  3 to 5 milligrams of mercury; the typical old-school mercury fever thermometer once found in nearly every U.S. household (and still stashed in some medicine cabinets) has 100 times more mercury—about 500 milligrams.

Just as with those old mercury thermometers, you can’t throw CFLs in the trash, which is an inconvenience. But here is the U.S. EPA list of the numerous locations where you can drop burnt-out CFL bulbs for recycling.

Keep in mind also that as long as electricity is being generated by coal power plants, those incandescent bulbs are releasing more mercury than CFLs, since the burning of coal produces mercury emissions that spread into air, soil, water, and the food chain. The EPA has estimated that due to its lower energy demand, using a 13-watt CFL prevents the release of 4.5 milligrams of mercury over its 8,000-hour lifespan.

“The Dollars Don’t Make Sense”

Some readers maintained that they steered clear of energy-efficient bulbs due to economics, not ideology. “With a cost of $20.00 each, it would take a while [to] get back the cost of that bulb in savings,” said Kobe Wild. “I’ll stick with fluorescent bulbs right now.”

Kobe’s analysis is correct for LED bulbs, but CFL bulbs generally are available for $5 per bulb. If you bought 10 CFLs to replace 60-watt incandescent bulbs, you would pay about $35 more in up-front costs, but if you used your bulbs about 1.9 hours per day (as one California study found was the average) over the course of a year, you’d save more than $37 on your utility bill, assuming the average U.S. electricity price of 11.9 cents per kilowatt-hour. That’s payback in less than a year.

LED bulbs currently appear to be available on hardware store websites for about $15 each, so a similar ten-bulb replacement purchase would cost a consumer $135 up front for only slightly more savings per year: $41. The payback period is, indeed, “a while”: 3.3 years. But as recently as 2010, a California utility study showed LED payback period was six years, showing how rapidly the costs are plummeting. Price aside, it’s interesting that a number of readers indicated that they’d be more favorable to LEDs than to CFLs.

“So What About Those LEDs?”

When Brian updates his story to concentrate on the (relatively) reasonably priced LED replacements with 2700K light, amazing life and no disposal problems, I hope his future headline notes that ‘conservatives’ are much more friendly to the environment and are therefore much better equipped to make decisions on green technology,” wrote Tom Mariner.

I asked study author Dena Gromet why LEDs weren’t included as an option. “We did not examine them simply because of the large price differential,” she replied, “as LEDs typically retail in the $20 range for one bulb as compared to much less expensive incandescents and CFLs.”

The economics of LED bulbs may have made a poor fit for the study, but they’ve improved enough to make the bulbs a more popular choice among consumers. The bulbs burn about 25 times as long as the old incandescents and three times as long as CFL bulbs, while using less energy to boot. That means LEDs save energy, save money, and even save hassle because they needn’t be changed as often. The bulbs don’t take time to “warm up,” they work with dimmer switches, and they feature more appealing light colors—some of which can be adjusted by user choice. LEDs also contain no mercury.

Based the rate at which technology is improving and the comments of liberal and conservative readers alike, there may indeed be a brighter future for energy-efficient lighting.

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