In 2001, Jim Gordon, a well-heeled developer of natural gas plants in New England, took up a long-discussed but never-pursued idea that advocates said would usher in a new era of clean energy in America: an ocean-based wind farm off the shores of Cape Cod.

"We knew from the beginning we had to pass two critical tests," Rodgers said. "We had to permit the project, and we had to finance the project. And when you're financing a project, novelty is bad. And we knew, by being America's first offshore wind farm, that we were going to be novel. So we wanted to make everything we could about the details of the project to be as un-novel as possible. We wanted the most optimal engineering site characteristics we could find."

The project's corporate developer, Jim Gordon's Energy Management Inc., which had been building natural gas power plants for nearly 20 years prior to taking interest in an offshore wind project, found in Nantucket Sound what it considered to be the most advantageous offshore spot anywhere from Maine to New Jersey: Horseshoe Shoal.

The shoal itself was sandy and shallow — generally less than 45 feet deep — which makes anchoring the turbines to the seabed easier, and the entirety of the 25 square mile project area, surrounded by the cape to the north, the islands of Martha's Vineyard to the west, and Nantucket Island to the east, would be protected from the often punishing, 50-foot swells of a stormy North Atlantic sea.

Sending the power generated by the giant turbines back to shore would be a relatively simple affair via undersea cables, and unlike the multiplying land-based turbines in the windy midsection of the country from West Texas to Nebraska and the Dakotas, Cape Wind would be comparatively close to the power-hungry metropolitan areas of the Northeast — another advantage, supporters noted. All of the turbines would also be at least 5 miles away from coastal properties — a sufficient distance, the developers had hoped, to avoid undue imposition on residents and summertime vacationers.

The 130 turbines, each standing 258 feet tall from water to hub and with anywhere from six to nine football fields of open water between them, would be as close to Craigville Beach as nearly anywhere, and their massive fiberglass blades would reach 440 feet above sea level — well higher than the tip of the Statue of Liberty's torch — at their highest rotation.

On a clear day, they would be unmistakably visible from this parking lot: A row of thin hash marks along the horizon, according to photographic simulations produced by Cape Wind.

A simulated view of what the windfarm would look like from the Craigville Beach area, according to Cape Wind's developers.

Collectively, the spinning turbines would have a nominal capacity of 468 megawatts, but this is an idealized energy-industry metric representing the site's output if the winds blew strong and steady at all times, and all turbines were spinning continually at maximum capacity. In the real world, of course, that never happens, and the average power output would likely be somewhere between 30 percent and 40 percent of that maximum capacity. Critics hew to the lower end of the range, supporters the higher, but Cape Wind estimates that the average output of the facility would represent about 75 percent of the typical electricity demand for the Cape and its nearby islands.

That may seem small, but backers have argued that a rapid expansion of offshore wind farms along the nation's coasts could provide, in aggregate, a substantial and reliable power resource. And from Cape Wind's earliest days, advocates noted that clean-energy development in the U.S. was already lagging woefully behind other parts of the world, principally Europe, which had already spent a decade developing offshore wind power by the time Cape Wind was first proposed. Today, there are more than 1,600 offshore wind turbines at 55 different facilities and representing more than 3,800 megawatts of capacity connected to the European grid, according to the European Wind Energy Association. Several that would dwarf Cape Wind in size and output are already being planned.

China, a gluttonous consumer of coal-fired electricity, nonetheless has at least one commercial-scale offshore wind farm of its own, and several more are in the works.

There are still no offshore wind farms in the United States.

To supporters of renewable energy, this is inexplicable, particularly given the imperatives of climate change and the comparative social advantages of clean power. A year of operation of a comparable coal power plant, Cape Wind's developers say, could produce as much as 1.5 million tons of carbon dioxide -- the leading planet-warming gas — and tens of thousands of tons of other airborne chemicals and pollutants, including nitrogen oxides, sulfur dioxides and asthma-inducing particulate matter. Natural gas-powered plants are much cleaner, but they still have abundant emissions.

A year of operation of an offshore wind farm like this produces no such pollution.

Of course, even accepting these benefits, opponents have fought tenaciously to keep it out of Nantucket Sound. As the project has inched its way through an obstacle course of state and federal agency approvals — 17 in all, by Rodgers' count — critics have challenged each approval with relish in court. In fact, the project has been in an indeterminate state for so long that it has been the subject of at least two books, hundreds of editorials and a pair of documentary films, including last summer's "Cape Spin" — described by The New York Times as a "tragicomic" look at one of the nation's most protracted energy infrastructure battles.

Cape Spin! Film Trailer from Rebirth Productions on Vimeo.

"It was the first offshore wind farm proposed in the U.S., and the nation lacked a clear regulatory path established for how such a project would get approved," Josh Levin, one of the film's producers, told the Times last June. "Whether you are a green person or not, whether you are a renewable energy person or not, whether you're a pro-business person or not, there is a cost to the United States having no effective energy policy."

Bogged Down