When it comes to the lights, Sean Kelly feels guilty.

He cares about the planet, but he also likes his 16 dimmer switches, which help him create the perfect ambience in his Queen Village trinity.

Kelly can't bring himself to switch to compact fluorescent lightbulbs, even though they use 75 percent less energy than incandescents and last up to 10 times longer.

"CFLs really are ugly," he says, glumly adding that his incandescents are "one of the most wasteful things I do."

As lifestyle changes go, what could be easier than screwing in a lightbulb?

But despite their eco-friendliness, the little swirls have yet to gain universal adoration, even among people who view themselves as greenies.

Experts like Steve Nadel at the American Council for an Energy Efficient Economy cites the same reasons for reluctance that I hear.

Like Kelly, many hate the light from CFLs and get impatient waiting for it to brighten.

They're scared of the mercury, a neurotoxin, inside.

They balk at the initial outlay. (Recently, I bought a CFL the equivalent of 60 watts for $4.48; a few steps away was a value pack of 60-watt incandescents for 42 cents a bulb.)

The federal Environmental Protection Agency recently tallied last year's sales figures and reports that one in five bulbs sold was a CFL.

It's a huge leap from the year before, and for that they can thank people like Philadelphia resident Cindy Newman, who switched over her whole house.

Or thought she had, until she took inventory. Among 41 bulbs - which seemed a lot to her, but the EPA says the average home has 45 - she realized a chandelier, a few reading lamps and the bathroom, porch and closet lights were incandescent.

"I've never before spent so much time thinking about my lightbulbs," she marveled.

As for me, I've been experimenting. It's partly to save money. CFLs ultimately save about $30 each over their long lifetimes because they use far less electricity.

And I wanted to do my part. The EPA says that if each household switched out just one bulb, the country would save $600 million in energy costs and 800,000 cars worth of greenhouse gas emissions.

Not long ago, I took my clipboard room to room, charting bulbs. Like Newman, I was shocked at the number - 69 - and at how many incandescents were lurking among them. Back to the store!

So now I've switched about half - all but dimmables (often problematic with CFLs), halogens (more efficient than incandescents, if not CFLs), and lights I hardly use anyway.

Finding the right color - CFLs simply look different - has been a process. The yellowish ones went into the outdoor fixtures. Instant bug lights! Those that made the place look like a bus terminal bathroom went into the basement.

Science, however, is improving the CFL.

By using a different kind of phosphor coating inside the bulb - it determines the light quality - engineers are improving the color.

Coming up with a dimmable CFL had been difficult because there's such a variety of dimmers, says George Mabin of Philadelphia's Westinghouse Lighting Corp. But now that's solved. Look for more of them soon.

The mercury content has lessened; the U.S. Department of Energy now says the risk is "negligible."

If anyone needs an excuse to give today's new CFLs a try, the World Wildlife Federation is happy to oblige.

On Saturday, they're sponsoring Earth Hour, which begins in New Zealand and marches west through many of the world's time zones before ending in San Francisco.

The idea is to raise awareness about climate change by getting people to turn off all unnecessary lights from 8 to 9 p.m. and then make a few lifestyle changes, like replacing at least one bulb with a CFL, before turning them back on.

Among the trophy spots going dark are the Sears Tower, Golden Gate Bridge, and 408 McDonald's arches in Indiana.

Plus the place where Sean Kelly works: Philadelphia's historic Eastern State Penitentiary will turn off the uplights that lend such drama to the massive stone walls. Not far away, the Cira Centre is turning off the 1,500 colored (low-energy) lights on its exterior.

I'll tune in and turn off, too.

Then I'll screw in the dimmable I just bought - a 25-watt equivalent for $7.98.

And give it a whirl.

GreenSpace: CFL Secrets for Success

After a lifetime with incandescent bulbs around the house, compact fluorescents can be confusing.

Some tips:

Codes for colors: Light from CFLs does not look like light from other sources. The U.S. Department of Energy recognizes six color categories, indicated by a number on the base of the bulb that ends with a "K." The range is from 2,700K (the most yellow, or "warm white") to 6,500K (the most blue, or "daylight"). Preferences seem to vary by region and demographics.

Other surprises: Only certain CFLs work with dimmers, timers and in low (outdoor) temperatures, although their numbers are increasing. Meanwhile, carefully check the fine print on the packaging and the base of the bulb.

Efficiency standards: Products marked "Energy Star" have met efficiency guidelines set by the federal government.

Cost savings: A typical CFL costs much more to purchase than a typical incandescent but saves even more money over its lifetime because it uses less energy and lasts far longer. Online calculators* can get very specific.

Mercury hazard: The new federal maximum of 5 mg for most bulbs (6 mg for higher wattages) takes effect in November, although the average bulb currently on the market already is in compliance, the U.S. Department of Energy says. The risk from 5 mg in a broken bulb is negligible, but it still must be cleaned carefully, the DOE says. The Environmental Protection Agency guidelines* include opening all the windows in the room for 15 minutes and scraping the debris into a sealable plastic bag or jar.

Disposal: Because of the mercury hazard, CFLs should be recycled (separately from household bottles and cans). Curbside pickup is rare, but some stores and various hazardous-waste programs accept them.*

The next big technology: LEDs (light-emitting diodes) are less-developed for household use than CFLs but promise even greater savings eventually.

* Links for CFL savings, recycling, disposal and other information, and - coming soon - a new blog: http://go.philly.com/greenspaceEndText

GreenSpace, a new column exploring the eco-lifestyle, appears every other week on this page. Contact staff writer Sandy Bauers at 215-854-5147 or sbauers@phillynews.com.