1 percent, 4.5 percent, 20 percent, zero.

Those numbers stuck in my mind after a boat tour of an offshore wind farm near Copenhagen.

One percent is, roughly, is the share of global electricity generated by wind.

4.5 percent is the share of electricity in the EU that comes from wind.

20 percent is the share in Denmark, the world capital of the wind industry.

And zero? That's the number of offshore wind farms that state and federal regulators have approved for construction in the United States. The Cape Wind offshore farm proposed for Nantucket Sound has been mired in controversy for years.

What a missed opportunity.

Offshore wind farms near population centers make environmental and economic sense, industry leaders say. They reduce greenhouse gas emissions and over time will cost no more than burning coal. About 30 reporters joined wind industry officials on the tour organized by the Global Wind Energy Association, which included presentations from executives from the world's top wind power companies. As my wise-cracking friend and Greenbiz.com colleague Joel Makower noted: "This is the ultimate in spin."

Up close and personal, the turbines are impressive. We got close:

The Middelgrunden Wind Turbines that we visited are a collection of 20 turbines, maintained and serviced by Siemens, and owned by an energy cooperative in Copenhagen and a utility called Dong Energy. They were built in 2000 and 2001 are relatively small–2MW apiece–meaning they provide electricity for about 24,500 homes. Many larger offshore turbines, built by Siemens and the Danish wind giant Vestas, have gone up since then. About 22 percent of the wind turbine in Denmark are located offshore.

"We have the largest amount of wind of any country in the world feeding into our daily operations," said Ditlev Engel, the CEO of Vestas. "No other country can beat that."