In 2002, federal reguators predicted it would take between 18-months and three-years for the proposed Cape Wind energy project in Nantucket Sound to receive federal approval. Nearly ten years later, the project is still awaiting full federal clearance, and has yet to begin construction. Full operation remains at least two years away.

On Friday, the Cape Wind project suffered yet another setback when the U.S. Court of Appeals for the D. C. Circuit vacated and remanded the Federal Aviation Administration’s determinations that the project would pose no hazard to air traffic. A unanimous three-judge panel concluded that the FAA had failed adequately explain the basis for its decision. Even though formal FAA approval is not required for the windfarm, the Interior Department has made its approval of the plan conditional upon FAA clearance and full compliance with any FAA-recommended mitigation measures. So until the FAA can provide an explanation for its “no hazard” determination the D.C. Circuit will accept, construction will be on hold.

Friday’s decision is not merely a setback for Cape Wind. It worsens the climate for offshore wind energy development more generally. The longer and more uncertain the regulatory process for such projects, the harder it will be to encourage private firms to invest — and the more difficult it will be to expand wind power offshore.

The Cape Wind experience also shows that it does not take much to gum up the regulatory gears for new projects of this sort. Opposition to Cape Wind has been driven by a few dozen families willing to invest their time and money to influence the regulatory process — and it’s worked. It does not matter whether a proposed project is popular with local residents, as a relatively small group of naysayers can exploit existing regulatory requirements to slow things down in the hope of eventually killing the project altogether. If other offshore wind projects are to succeed where Cape Wind has (thus far) failed, they must prepare for similar opposition, and encourage regulatory reforms that will streamline wind project development and approval.