Green technology has always been perched on the verge of the big time. Advocates of wind power, solar cells, and hydrogen vehicles promise that any day now, they'll blossom from science-fair projects into major businesses, competing squarely with the cars we drive today and the energy sources we use now.

But trying to disrupt well-established industries such as transportation and utilities is a risky proposition. No one's sure how quickly green tech will be adopted, which puts a premium on astute timing — and endurance. Some signs, though, indicate that the tipping point could be near. Big companies are placing their bets. "We expect the wind industry to grow at double-digit rates for the next 10-plus years," says Steve Zwolinski, CEO of General Electric's wind-energy division, which employs 1,800 people globally. And around the country, imaginative people are working to expand markets for green technology, building prototypes, cultivating public support, raising money, and collaborating with others interested in fostering its growth. To understand the innovative approaches being applied to reinventing the world's energy economy, Fast Company visited three leaders of green tech's latest charge.

Reaping the Wind

Jim Gordon was only going over to Walter Cronkite's house for coffee and muffins one morning in August 2003. But for Gordon, an entrepreneur trying to build America's first offshore wind farm, this was a high-stakes coffee klatch. The most trusted man in America had recorded a series of radio and TV ads for a group that opposed Gordon's project, and Gordon knew that it would be a tough slog to get the wind farm built with such a respected journalist serving as the public face of his foes.

Gordon, who built and operated a handful of natural-gas-fired power plants around New England in the 1980s and 1990s, knew that he'd have to deal with opponents when he decided to try to build a wind farm in the middle of Nantucket Sound (between Cape Cod, Nantucket, and Martha's Vineyard, where Cronkite had a home). "We've had opposition on all of the projects we've developed," he says. "By nature, energy projects are controversial, and sometimes people don't want to live near them."

Still, Gordon says, "I wasn't prepared for the ferocity." A well-funded group, the Alliance to Protect Nantucket Sound, cropped up and recruited Cronkite and historian David McCullough as its spokesmen. Senator Ted Kennedy wrote an editorial in the Cape Cod Times opposing the project. His nephew, Robert F. Kennedy Jr., had spoken out against it too — despite serving as the senior attorney for the Natural Resources Defense Council, which supports wind power in general. (Though Gordon's wind turbines would be visible from the famous Kennedy compound in Hyannisport, Robert Kennedy has said he opposes this plan because "we wouldn't build a wind farm in the middle of Yosemite.")

Even though wind-power technology was finally ready to compete with traditional oil- and gas-burning power plants — especially with oil prices spiking — Gordon quickly realized that the technology would be only half the battle. His plan might be innovative and earth-friendly, but if he wanted it to fly, he'd have to battle on an entirely different front. Image making, public relations, advertising, and lobbying would ultimately determine his project's fate.

Gordon sold his natural-gas-fired plants in 1999 and began exploring the possibility of developing a large wind farm. To him, the site in Nantucket Sound made infinite sense. "Over the past 20 years, the technology has made quantum leaps," he says, "and the indigenous renewable energy source we have in New England is wind." Within New England, Nantucket Sound offers some of the most consistently strong winds. It didn't hurt that Gordon's Boston-based company, Cape Wind Associates, could erect its 130 wind turbines, each rising 420 feet from the water, without buying or leasing the land beneath them; it would only have to navigate a complicated permitting process involving 17 state and federal regulatory agencies. (Cape Wind plans to buy its turbines from General Electric.)

At peak capacity, Gordon says his wind farm would produce enough power to supply the entire Cape, plus the islands of Nantucket and Martha's Vineyard, while emitting zero pollution. It could reduce utility bills for consumers and businesses in Massachusetts. And besides pumping out 23,000 tons of sulfur dioxide every year, the Cape's existing power plant was involved in an oil spill in nearby Buzzards Bay in 2003. The power plant's smokestack rises 500 feet above the Cape Cod canal, higher than Gordon's turbines would. Still, his opponents charge that the wind farm will be unsightly, hurt tourism and fishing in the region, kill migrating birds, and pose a hazard to passing planes and boats.

So Gordon and his small company have been executing a complex and persistent plan of public information and lobbying to try to win approval for their project, which would be the biggest wind farm in the United States. "We spend about 70% of our time on the engineering and design of the project," he says, "and 30% on public-advocacy issues." He has hired Republican and Democratic lobbying firms in Washington, as well as a separate lobbying and PR firm in Boston. They've helped set up meetings with several of the state's congressional representatives. (Ted Kennedy has so far declined to meet with Cape Wind.) The company ran its own radio ads during the Democratic National Convention in July. One delved into Cape Cod's history of windmill use, which dates back to the American Revolution, when salt produced on the Cape from seawater pumped by wind power helped supply George Washington's army. Gordon has visited an offshore wind farm in Denmark that is located near a popular recreation area and brought a delegation of Danes to the Cape to talk about that project's impact on tourism and property values. "They said that they were concerned initially, but now they advertise visits to the wind farm in their tourist brochures," Gordon says.

One-on-one conversations can change opinions in a way that radio ads can't, says Chris Sherman, Cape Wind's manager of project development. So the company has sent reps door-to-door on the Cape and participated in more than 400 public education events — some organized by opponents of the project. "People are concerned about energy independence and environmental issues, and you try to capture those in a 60-second ad, but it's impossible," Sherman says. "Hands down, the most successful thing is sitting behind a table at an event like the Barnstable County Fair. It puts a face on the project."

One of the most important face-to-face meetings was Gordon's conversation with Cronkite in the summer of 2003. Cronkite had not only appeared in television and radio ads that questioned the wisdom of erecting wind turbines in Nantucket Sound, but he had also written a column on the topic that was syndicated in more than 175 newspapers.

"I called him on the phone," Gordon says, "and he was gracious enough to invite me to his home and give me two hours of his time." Gordon says he showed Cronkite nautical maps indicating the turbines would be built in an extremely shallow part of the sound that most large boats avoid. He presented pictures of what the turbines would look like from shore — "tiny half-inch sailboat masts on the horizon," as Gordon describes them.

Gordon spoke with Cronkite on the last Monday of August 2003. Later that week, after speaking with scientists from an oceanographic institute, Cronkite decided to ask Gordon's opponents to stop running the ads that he'd recorded. He spoke with the Associated Press and local newspapers, telling them that he felt the project deserved a full review by the Army Corps of Engineers. He wrote another column, this time urging the corps to "clear its bureaucratic cobwebs and expedite this matter so urgent to our health and Earth's future." Cronkite made clear that he wasn't yet a proponent of the Cape Wind project but that Gordon had at least managed to persuade him to keep an open mind until government agencies such as the corps weighed in.

Gordon hopes construction of the $750 million wind farm will begin in late 2006 or early 2007 and take about two years to complete. He says that despite the opposition, he wouldn't rule out trying to build a second wind farm. "The pioneer always has to face the slings and arrows," Gordon says. "But we're paving the way, making it easier for our next project, or for those who come behind us."

"I envision it," says Gordon, whose family has owned a summer house on the Cape for 30 years. "When I walk on the beach, I see it out there."

Here Comes the Sun

Matt Robinson, clad in a long white lab coat and blue gloves, is tending to a shiny silver machine called a Mini-Labo. It resembles a pasta maker, but it doesn't churn out lasagna noodles. Here in the clean room at Palo Alto-based Nanosolar, Robinson feeds a thin ribbon of aluminum foil through the machine; when it emerges, it looks as though it has been coated on one side with a flat black paint.

Robinson is testing the process by which Nanosolar hopes to make a new kind of lightweight, flexible, and low-cost solar cell. The black paint is actually a solution containing millions of nanoparticles that are made to be "self-assembling" — that is, they align themselves into the structures necessary to transform the sun's photons into electrons. This is called the "light-absorbing semiconductor layer," one of a dozen different chemical strata that will be applied to a sheet of foil to enable it to generate electricity from the sun.

Nanosolar's product is still in the test phase, and the Mini-Labo isn't designed for large-scale production. So after a few feet of foil have spooled out of the machine, Robinson leans in close and adds a bit more of the solution to a reservoir, using what looks like a small eyedropper. Nanosolar chief executive Martin Roscheisen chronicles the test with a camera.

If it seems simultaneously high tech and hand-to-mouth, well, that's life at this low-key company headquarters, adjacent to the Palo Alto dump. Roscheisen is a successful Internet entrepreneur who sold his previous company to Yahoo for $450 million. He and Nanosolar embody the new ethos of Silicon Valley innovation, postbubble: less hype and more concern about wringing the greatest possible value from every dollar. He financed the company with a combination of venture capital and government grants. And he created a frugal corporate culture that aims to get the recipe for its new solar cells right before it moves into full production.

The purse strings may be tighter these days, but the ambitions are still big. Along with industrial giants such as Sharp, Kyocera, and BP, Nanosolar is after the solar industry's golden ring: a reliable photovoltaic cell that can produce electricity from sunlight at a cost that is competitive with electricity from the existing power grid. According to Roscheisen, it costs roughly 32 cents to produce a kilowatt hour of electricity using existing solar-cell technology. (One kilowatt hour is about enough juice to run one dishwasher cycle.) That's about three times the cost of electricity purchased from the local utility, which was likely generated by a plant that burns coal, oil, or natural gas. "Our eventual goal is to generate electricity at less than the grid cost," Roscheisen says, although he concedes that the company's early products won't hit that mark everywhere in the world.

Sunlight is free, of course. The added cost comes because it's still so expensive to manufacture solar cells relative to the power they dribble out. To solve that problem, Roscheisen wanted to get a sense for how solar cells were being made and what breakthroughs academic researchers were achieving. He visited factories around the world and spoke to researchers at Cambridge University, Sandia National Laboratories, the Swiss Federal Institute of Technology, and Stanford. He discovered that one new approach to producing solar cells involved "printing" them in much the same way magazines like this one are printed: by rolling a flexible sheet through a machine, layering on liquids, and then drying them, eventually yielding a sheet that can convert photons into electricity.

Roscheisen funded the company's early research himself, and with angel investment from friends such as the founders of Google, but eventually he decided to raise $6.5 million in venture capital. The company received an additional $10 million in research grants from such agencies as the National Science Foundation, the California Energy Commission, and DARPA, the Defense Advanced Research Projects Agency.

Roscheisen decided to focus the company on creating solar cells that would be used on the roofs of buildings and by utilities that wanted to generate vast amounts of electricity. "That's the largest application area today, and we can come in at a much lower cost, with easier installation," he says. Nanosolar's product will be 100 times thinner than conventional panels that are placed on rooftops, and weigh one-twentieth as much.

Next year, Nanosolar will set up a factory for a first generation of solar cells slated to hit the market in 2006. But first, Roscheisen knows, Nanosolar has to perfect its recipe and figure out how to crank out large quantities of high-quality cells. With big rivals breathing down its neck, there's not a moment — or a dollar — to be wasted.

On the Road to Hydrogen

Kyo Hattori is standing in a parking lot, gushing about the hydrogen-powered Nissan he drove yesterday. "It was smooth and quiet," he says. "Very nice."

What's odd about the praise is that Hattori works for Toyota, Nissan's archrival. "We at Toyota felt strong stimulation from the back," Hattori says, poking me emphatically in the spine with his forefinger.

Here at the California Fuel Cell Partnership in West Sacramento, engineers from car companies and fuel distributors such as Shell and ChevronTexaco are working in tandem to define some of the standards and procedures for fueling, operating, and maintaining fleets of hydrogen fuel-cell vehicles. And though the garagelike work bays that belong to each automaker are off-limits to competitors, one important element of the collaboration is the regular chance to test-drive one another's vehicles to see how the latest generation performs.

The odds are stacked against replacing an established technology such as the gas-powered internal combustion engine overnight. But the partnership's members realize that those odds become a lot less daunting if they can rely on a well-oiled alliance.

While car companies, fuel companies, fuel-cell manufacturers, and government agencies had all been conducting their own experiments, the partnership's West Sacramento site, opened in 2000, provides a technological sandbox where they can all play together. "We use the word 'coopetition' a lot here," says Catherine Dunwoody, the partnership's executive director. "These engineers are extremely competitive, but they have lots of reasons to cooperate if they want to see the United States develop an infrastructure to support hydrogen vehicles."

The 20 partnership members — ranging from BP to Volkswagen to United Technologies to the U.S. Department of Energy to Hyundai — conduct their own research and development. But they wanted to be able to share a single hydrogen fueling station so that they could make sure that it was designed to work with all of the vehicles, and vice versa. Partnership members also share some equipment, such as an indoor, car-sized treadmill for testing. Shared equipment, as well as the regularly scheduled group test-drives, promotes interaction among the members.

The partnership also holds regular open houses, inviting the public to the facility for test rides. That's vital, says Adam Gromis, program specialist at the partnership, because many consumers have one association when they hear the word "hydrogen": the Hindenburg. While hydrogen is susceptible to leaking and igniting more easily than gasoline, it actually has much less explosive energy by volume. And the only output from the tailpipe of a hydrogen car is warm water vapor.

By 2007, the partnership hopes to help its members put 300 fuel-cell vehicles on California's roads. Currently, there are just 37. The vehicles are still prohibitively expensive. One Toyota staffer, Darryl Umale, puts the price of a prototype hydrogen- powered Highlander SUV into context by remarking, "You are looking at 20 Lamborghinis." But Toyota is here, alongside General Motors, DaimlerChrysler, and others, to try to bring that price down and to make hydrogen-powered vehicles a viable option. "Everyone who's involved with the partnership knows that they need one another to succeed," Dunwoody says. "If any one of them were to try to do it alone, they couldn't make it work."