There are already more than 20 offshore wind farms in Europe, as opposed to none in the U.S. Opponents, including beachfront homeowners, claim that such installations would threaten avian and aquatic life and ruin scenic vistas.
Onshore, U.S. wind-power capacity is growing fast, thanks to federal tax credits and state laws encouraging the production of energy form renewable sources. In 2007, U.S. wind-power generating capacity grew by 45% to nearly 17,000 megawatts per hour, second only to Germany.
Wind turbines in the U.S. are expected to generate about 48 billion kilowatt hours of energy this year, or enough to power about 4,5 million homes. Even so, that is only about 1.2% of the nation’s demand for electricity. By comparison, wind already meets about 20% of Denmark’s needs and about 12% of Spain’s.
Because of favourable wind conditions, much of the U.S. construction to date has been in areas far from big population centres. In many cases, transmission systems lack the capacity to move all of the resulting electricity to where it is most needed.
Building offshore would allow developers to produce electricity closer to big cities, particularly along the East Coast. The downside is that it would also boost construction costs by 30% or more.
Another key benefit of offshore wind power is the lower rate of wind turbulence at sea vs. on land. Sunlight penetrates the water evenly, resulting in a more even range of temperature directly above the water surface, thus reducing irregularity in the flow of the wind.
Less wind turbulence means that the height of the offshore wind turbines can be lower than similar models on land, as well as potentially longer lifetime for the turbine.
Source: WSJ, 20/06/08
