AURORA, Colo.—Rows of little plastic domes dot the roof of the new Wal-Mart Supercenter here, looking like a marching band of "Star Wars" R2-D2s.
Inside each dome, a trio of computer-aimed mirrors tracks the sun and bounces its light down a reflective shaft and through a milky white lens, illuminating the stockroom below.
The skylight idea is centuries old. But the mirrors, the lenses and dozens of other energy- and environment-saving innovations are new, and they're showing up not just at Wal-Mart but at other companies, schools and public agencies.
In addition to the Wal-Mart's legion of skylights, for example, the store's foundation is made of ground-up chunks of runway recycled from Denver's old Stapleton International Airport. Porous paving in its parking lot soaks up and filters polluted storm-water runoff. Huge north-facing windows provide most of the store's interior light. Used motor oil from the tire and lube shop helps heat the store, as does old vegetable oil from the deli.
According to Don Moseley, senior Wal-Mart engineer for environmental innovation, these and other efforts "are good for the environment and good for our business."
That's the mantra of the so-called green building movement that's sweeping the nation. Among the adherents are financial institutions such as Citigroup, PNC and Bank of America; automakers such as Toyota, General Motors, Ford and Honda; and such retailers as Wal-Mart, Target, Home Depot, Lowe's, Chipotle and Patagonia.
The next two new Major League Baseball parks, in Minneapolis and Washington, D.C., are poised to go green. So is the biggest privately financed development under way in the United States: MGM Mirage's $7 billion Las Vegas City Center, due in 2009.
Future federal buildings will be green, too. The General Services Administration, the nation's biggest landlord, announced last spring that it was applying stringent green-building standards to its $12 billion construction portfolio of courthouses, post offices, border stations and other buildings.
States also are cracking down. Washington state began requiring in April 2005 that all state-funded construction projects larger than 5,000 square feet, including school district buildings, be built green. Many other states—including California, Arizona, Arkansas, Colorado, Connecticut, Florida, Michigan and Nevada—have followed suit. So have nearly 60 cities and counties nationwide.
Scores of colleges and universities—including Emory, Pennsylvania State, the University of Florida, the University of South Carolina and the University of California-Merced—also have taken the pledge. Harvard University alone has 12 green buildings.
Scads of students at architecture and interior design schools share the green zeal. "It's hugely, hugely, unbelievably popular," said Sylvie Sugg, 21, an interior design student at the Art Institute of Colorado in Denver. "Green is so big now that people shouldn't go into design if they don't like it."
The job market for grads with green credentials varies widely from city to city, reflecting the trend's ongoing spread from West to East. In general, green grads do well, according to Kira Gould, the incoming chair of the American Institute of Architects' environment committee. "I see a lot of firms looking for expertise in green buildings at all levels," she said.
The key to the movement is a new set of standards that's far more demanding, environmentally speaking, than local building codes. The movement invites innovation because it's based on environment-protecting performance standards, not rules. That leaves it up to architects, builders and designers to decide how best to reduce energy and water consumption, for example, or workers' dependence on cars.
The U.S. Green Building Council, a Washington, D.C. -based alliance of some 7,200 architects, builders, land use planners and academics, issued the first set of standards in 2000, covering big commercial construction projects. Standards for existing buildings and commercial interiors came out in 2004. Criteria for new single-family homes, public schools, hospitals and cookie-cutter commercial buildings such as bank and retail store branches will come in the next year or two.
The council's goal is to "transform the marketplace" in real estate in the United States and globally, said Rick Fedrizzi, the council's founding chairman and chief executive officer. "We'll be at that point" in the movement, Fedrizzi said recently, "when it's no longer called green building; it's just the way building is done and they are simply called buildings."
In fact, council-certified green buildings have been spreading like wildfire since 2000. In that year, about $790 million in new commercial construction met the council's standards. This year, about $7.2 billion does. In 2000, a few hundred projects sought council approval. Today, more than 4,900 have registered for certification.
The council's determinations are based, like a report card, on a numeric calculation of improvements in building performance. Relocating executive offices from a building's outer shell to its core so that more employees work in natural sunlight, for example, helps to earn a point.
Building on a cleaned-up former hazardous-waste site or vacant inner-city lot helps, too. So does recycling an old building's rubble and using renewable bamboo flooring rather than oak. So does planting rooftop vegetation for its insulating and runoff-reducing effects and seeding the building with motion detectors that turn off lights and computers when they're not being used.
Independent outside contractors grade the applications and the council awards certificates to projects that earn at least 26 points under its Leadership in Energy and Environmental Design program. Those that rate 33-38 points earn LEED-Silver, 39-51 points LEED-Gold and 52-69 points LEED-Platinum.
A burgeoning market offers new building materials and technologies to help builders score points. The council's GreenBuild convention last month in Denver was swarming with exhibitors of waterless urinals, recyclable industrial carpet, low-energy LED lighting systems, soybean-based fabrics, insulating window glass and other wares.
Ray Anderson, the founder of Interface Inc. of Atlanta, which makes office carpets entirely out of recycled material, offered two telling numbers that reflect the movement's growth: 135, the number of attendees when Anderson attended the Green Building Council's first convention in 1998; and 13,000, the estimate of the Denver convention attendees.
LEED's share of commercial construction doesn't seem like much: It's up from 0.7 percent in 2000 to 5 percent in 2006. But in a slow-to-change industry, the transition is huge and sudden, said Charles Lockwood, a busy green-building consultant.
In a Harvard Business Review article last June, Lockwood likened the movement's influence over construction to the transformations that electricity, elevators and air conditioning wrought in the late 19th and 20th centuries.
"Those changes rapidly made older buildings obsolete," Lockwood said in an interview, and he predicted the same effect for buildings that now are being exposed as energy-wasting and environmentally costly. Big commercial-property owners already are reviewing their portfolios with an eye toward dumping some holdings and upgrading others, according to Lockwood, who advises some of them.
It's easy to imagine a green building rout in the next few years, based on the virtually unchallenged logic that buildings in an era of global warming need to be designed to minimize their environmental impact. Already, some retailers, such as Patagonia and Chipotle, are marketing their greenness as an attribute that sets them apart from competitors.
That's likely to accelerate with the council's upcoming release of a performance-rating system for generic store designs that retailers such as Starbucks and Whole Foods rely on for their new construction nationwide. If the council influences those portfolios, thousands of green buildings will start popping up across the country at viral speed.
"A lot of us think retail is the tipping point," said Kim Hosken, the council's director for new construction.
Headwinds of resistance to the movement also are building, however.
For one thing, building green, at least until recently, was presumed to cost more upfront but to pay off in the long run through lower operating expenses.
"You will spend more on insulation and windows," said Glenn Munro, a Toronto-based retail shopping-center developer. "But you'll save on electrical costs by downsizing the air-conditioning and heating systems and so on."
That takes patience. Governments and universities have it because they tend to own their buildings and keep them for generations. For the same reason, retailers such as Wal-Mart, Home Depot and Target, which generally own their real estate, find it relatively easy to go green.
But for retailers such as T J Maxx, Pottery Barn and legions of others who lease their properties, there's little to gain from greening. Any savings on properties that they lease generally would go to landlords. And landlords, who often own properties only briefly and do business in highly competitive markets, will be hard to excite about green building.
A variant of that problem arises with new-home buyers, said Michele Myers, a custom-home builder in the Durham, N.C., area. Whatever the long-term savings on heating and cooling bills, she said, buyers rarely choose to spend more up front on energy-efficient appliances and extra insulation.
"The paybacks are too far down the road for most people," she said. "LEED may be great, but it's for the affluent, not the majority of Americans out there."
But that may be changing. The added costs of green building—long assumed to be 10 to 20 percent more than traditional construction—are falling and may have been exaggerated, according to some who've built green recently.
"There's an assumption of a green premium, but we haven't found that," said Jeffrey Smith, Harvard's director of facilities maintenance.
Smith's greatest surprise, he said in an interview, was "how interested building occupants are in these projects. It's almost as though they're looking for something they can believe in."
David Abeloe, the director of Patagonia's huge, LEED-silver national distribution center in Reno, Nev., said he discovered something similar: a work force that's enthusiastic about its workplace. Abeloe thinks that his employees are repaying Patagonia's investment in natural light, radiant heat and high-exchange air circulation, among other measures, with better productivity. It's a common but hard-to-measure claim often made for green buildings. Abeloe based his on worker error rates.
"Some companies in our industry are happy with error rates of 1, 2, even 3 percent" of their shipments, he said. "Ours is a fraction of a percentage point. "
A more basic argument for green building came from Wal-Mart's Moseley: "The huge majority of changes we're making are financially beneficial."
The U.S. Green Building Council's Web site is www.usgbc.org.