On Wednesday, Interior Secretary Ken Salazar finally approved the Cape Wind Project in Massachusetts, clearing the way for what he said “will be the first of many projects up and down the Atlantic Coast.”

The approval is sure to set off a scramble to push forward stalled offshore projects. There are about a dozen pending in the U.S., and according to the American Wind Energy Association they represent as much as 2,500 megawatts of green power. Experts say the U.S. could easily get a fifth of its electricity from wind, and some say that the wind potential of just a few states (Texas, the Dakotas) could power the entire grid.

Although Salazar slightly trimmed the size of the project from 170 turbines to 130, ordered some light dimming and requested that the towers be painted off-white to blend into scenic Nantucket Sound, he left no ambiguity that this long-delayed project — mired in a regulatory fight for nine years with implacable foes — was now cleared for takeoff. “We hope to begin construction of Cape Wind before the end of the year,” said the project’s developer, Jim Gordon. Completion could come as early as 2012.

But despite the air of finality around the federal Record of Decision, the opposition is far from vanquished. Salazar’s words were still hanging in the air when “a coalition of stakeholder groups” lead by Cape-based Save Our Sound announced that it would immediately file suit. Not content with simply saying the secretary ruled the wrong way, the coalition accused him of “trampling the rights of Native Americans and the people of Cape Cod.” And it said his decision violated (take a deep breath here) the National Environmental Policy Act, the Migratory Bird Treaty Act, the Rivers and Harbors Act, the Clean Water Act, the Outer Continental Shelf Lands Act, and the Lobster Freedom of Assembly Pact. (Sorry, made up that last one.)

Native groups did indeed hold up the project for a time, and they are also talking about suing now.

The assumption that the rights of Cape residents have been trampled is a bit disingenous, since some polls show them favoring the project, in one case by as much as 55 percent. Here's how some residents took the news:

I talked to Audra Parker, the fire-breathing head of the Alliance to Protect Nantucket Sound (aka Save Our Sound) and she didn’t sound conciliatory. “Already, 10 parties have announced their intention to sue,” she said. Parker admitted to having been set back in the lower courts “two or three times,” but whenever her group loses anything they appeal, so the state Supreme Court has several of those cases — keeping the fires burning for the opposition. Parker also has hopes that the Federal Aviation Administration will deny a final permit.

I’ve visited Parker in her Cape office, and her determination is palpable. I asked her if there’s any possibility that the group could finally concede defeat. No, she said, “We will fight until we win.”

Cape Wind has been forced to spend many millions defending itself in court, so it will now have to find considerable entrepreneurial capital to finance the estimated $1 billion cost of building Cape Wind. The facility, with turbines from German giant Siemens (a switch from GE), would provide enough power for 400,000 homes.

The turbines are 400 feet high, but at more than five miles from shore will not exactly dominate the landscape. As Reuters put it, they will “be visible on the horizon from parts of Cape Cod.”

I visited Denmark specifically to get a look at the country's pioneering offshore wind farm, and found myself standing on a beach dotted with old German gun emplacements. The towers were barely visible from there. In fact, at a comparable distance to the Cape Wind site, they could have been a mirage. And perhaps it is a mirage that the opposition is pursuing in its ongoing fight to stop the country’s first offshore wind development.

Opposition to this project also reminds me of another trip, this one to West Virginia to see mountaintop removal mining sites. Environmental groups there oppose "industrial" wind power as an alternative to just decapitating ancient peaks. They don't want to look at wind towers either, but do they prefer ravaged, heavily polluted mining sites? And, of course, the oil even now drifting toward protected coastline in Louisiana shows the folly of relying on conventional sources of energy. Did I mention that Cape Cod is now served by a dirty coal plant?

Jim Motavalli ( @jmotavalli ) writes about cars, technology and the environmental world to anyone curious enough to ask.

Mighty wind: Cape project wins approval, but opposition is still full of hot air
Cape Wind won decisive approval triggering a potential green energy gold rush. But the opposition -- which mainly just doesn't want to look at wind turbines --