By now, it seems, almost everyone knows what it takes to go green. We can rattle off the list - sustainability, energy efficiency, renewable resources, fewer chemicals, regional food sources - and, mostly, we're all for them.

But when it comes to the often-garish glow of compact fluorescent light bulbs, we can't help but wonder: Isn't it possible to light a space responsibly yet attractively? Does living green mean we have to look green, too?

It's a question restaurateur/activist Judy Wicks has been pondering in her efforts to make her three adjacent Victorian rowhouses in University City more environmentally aware and efficient.

"The look of going green is mostly things you don't see - how you heat your water, where your food comes from, what you do with waste," says Wicks. "Green isn't a static way of being. It's a journey."

Along with installing a tankless solar hot-water system and replacing the buildings' old windows with modern double-pane models that help lend a natural glow and warmth, Wicks began working on the lighting at her White Dog Cafe last year.

Energy efficiency is her first priority; making both the restaurant and its customers attractive is her second. Re:Vision Architecture in Manayunk, which has been overseeing other eco-upgrades to the White Dog, the Black Cat shop next door, and Wicks' home above her businesses, has taken on the challenge.

"In a case like hers, a restaurant where people must look as aesthetically pleasing to each other as the food does to them, the quality of light is crucial - the type of fixture and the kind of light they produce," says Re:Vision's Jeremy Avellino, an architect/designer and former builder.

For now, he has chosen compact fluorescents (CFLs) that cast a surprising bluish light. They'll use nearly one-quarter the energy incandescent bulbs would and will last 10,000 hours or more.

CFLs produce varying shades of white light, identified by color temperature measured on the Kelvin scale, according to the Environmental Protection Agency's Energy Star Web site ( Lower Kelvin numbers mean the light has a warmer color; higher numbers mean the light has a cooler cast. But not all manufacturers list color temperature on their packaging.

Most CFLs on the market offer soft or warm light (2,700K to 3,000K), comparable to an incandescent, that will enhance warmer room colors such as red, yellow and orange, the Web site says. At higher Kelvin color temperatures (3,500 to 6,500K), CFLs will emit more white to bluish-white light that enhances cooler colors (blue, green, violet).

"Our eyes have been tuned to incandescent bulbs for years," Avellino says. "After you get used to compact fluorescent . . . people look better."

But even in mid-renovation, decisions are being reconsidered at the White Dog. The CFLs are an interim step, to be replaced ultimately with light-emitting diodes (LEDs).

"There are so many environmental issues surrounding manufacturing [CFLs] and their disposal, as they have toxic waste [mercury] in the bulb," Wicks says.

LEDs are the next wave because they are more environmentally sound, use less energy and last longer than both CFLs and incandescents, Wicks and Avellino say.

And the light they cast allows for any number of tones and moods. "You can totally name your color," Wicks says.

Though she is starting to use LEDs in exterior lighting, as the technology advances Wicks plans to use them inside, too - they are easier to dim, an important feature for a restaurant.

For an eco-conscious statement of a different sort, look no further than the work of lighting designer/sculptor Warren Muller.

With his partner, interior designer R.J. Thornburg, Muller runs Bahdeebahdu, the design firm whose gallery space moved after a recent fire from Cherry Street in Old City to American Street in Northern Liberties.

Muller's lighting ideal has always been environmentally aware. In his designs, he uses life's flotsam and junk: old brass instruments, discarded crystal candy dishes, colanders, antique glass jars, car and motorcycle parts.

"I've always come from a place of using what's available - found objects, trash," Muller says of the pieces he's been executing for more than 25 years. "People throw away so much of everything. That gives me the freedom to be playful with my work."

He commands $2,500 to $250,000 per project.

Being ahead of the game in repurposing what's available is what led developer Tony Goldman to Muller's door.

Goldman Properties helped create New York City's SoHo district and Miami's South Beach from once-trashed warehouses and old hotel spaces. In Philadelphia, he's taken on a once-worn-out area of South 13th Street between Locust and Chestnut.

"He does what I do with his buildings," Muller says of Goldman. "He takes what's been disregarded, ignored and nearly discarded, sees their value, and brings them back to life."

Goldman hired Muller for his latest project: rehabbing the lobby of the Philadelphia Building, which houses not only Goldman's offices and Naked Chocolate Cafe, but new mixed-use loft and studio spaces dedicated to what Goldman managing director Craig Grossman calls "the artist class."

First, Muller created from bits of the old colonial-style chandelier in the lobby a fixture that looks like a deconstructionist spider web. There are bits of old, tangled copper and gilded tubing, and scads of crystal plates, disks and orbs that look like prismatic butter dishes and serving trays.

The light cast by the new chandelier's super-low-wattage incandescent bulbs seems to shimmer and shine. The prismatic effect is best when the light bounces off lit-from-below-floor-level steel cages Muller filled with old olive-oil bottles he found in an abandoned factory in upstate Pennsylvania.

Whether you spy the fixture on Juniper Street or walk into the lobby, you're awash in a gold-and-white glow. Unlike most light conservationists, Muller disdains compact fluorescents.

"Those low-voltage twisty, curly bulbs everybody goes crazy for? I don't like their light quality," he says.

Usually, he prefers fiber-optic lighting because it has a single source and can be used "outdoors or underwater, as it's not affected by weather." Muller simply changes the aesthetic level of warmth and cool with filters, at his whim.

"The fiber optic is transmitting from a source in the distance, so that you have one bulb - 150 watts, halide - in a box, and you can run the lighting as many feet away as possible. And there's no heat involved."

Does fiber-optic lighting burn as long and as economically?

Muller points to the fact that he used the same 150-watt bulb in his studio's most noticeable piece - a ladder sculpture lined with light that hadn't been turned off in three years.

"Only the fire made me unplug it," he says.