Offshore Potential for Eastern US

Sometimes it is worthwhile to dream big.  And there was an article in North American Windpower about a study on offshore wind potential in the Mid Atlantic Bight, that runs from Cape Hatteras to Cape Cod on the Eastern seaboard of the US, that does just that.

The area has a broad sand and gravel shelf, which is good material to construct wind turbine foundations.  And it is in an area that lacks category 5 hurricanes.  The study analyzed the potential for using water depths less than 20 m, which is the current depth used by conventional offshore turbines, 20-50 m, which is the depth that some new foundation designs have been validated for, and 50-100 m, which would need some new designs.  In addition to water depth, other areas were excluded for bird flyways, shipping lanes, chemical disposal sites, military restricted areas, zones of unexploded mines etc.  The model proposed that turbines would be a generous 10 rotor diameters apart, in order to minimize wake losses.

In total, the model showed about 45,000 sq km from 0-20 m depth, and additional 77,000 sq km at 20-50 m, and an additional 67,000 sq km at 50-100 sq km.

But it was when the power output was estimated that it got interesting.  If only the 0-20 m depths were used, the wind turbines could provide enough power to meet 82% of the total electric load of the adjacent states.  And the adjacent states are heavily populated, including New York, New Jersey, Virginia, North Carolina, and several smaller states.  If all depth to 100 m were used, then the wind could supply all of the energy currently used for building heat from oil, natural gas, all electric load for all uses, and all the energy used by light vehicles (assumes a conversion to electric or electric hybrid vehicles – it was assumed this would be integrated as a diverse backup system for the wind).  And all of this would consume only 64% of the wind energy available.

Some people critcize such studies as “pie in the sky”, or unrealistic.  And of course they are to some extent.  Will it ever be built?  Clearly not.  Among other things, who says we need to rely on only offshore wind?  There are lots of other renewable energy resources in the mid Atlantic states, including hydro, biomass, solar, on shore wind, geothermal etc.  Sprinkle in some conservation, and some other renewable energy, and a good dose of offshore wind, and even the densely populated mid Atlantic area of the US can develop a sustainable energy system.

And that is the value of this study.  It demonstrates that we are not limited by the resource.  We are only limited by our resourcefulness, and creativity.

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