Tuesday, October 21, 2008

Wind Turbines Offshore in Deep Water For The Northeast US

The state of New Jersey is helping to fund an initiative by Garden State Offshore Energy to build wind turbines 16 miles offshore. The state would like to have 3000 megawatts of wind power from offshore wind farms by the year 2020, which is 13 percent of the state's electricity needs. The Garden State initiative will provide 350 megawatts of electrical power, and represent the US's first deepwater wind turbines.

Proposed wind turbines in this country have been challenged diligently by the public and shipping interests and this has slowed or outright stopped some proposed offshore wind farms. With the deepwater turbines this is no longer a problem. When the turbines are closer in to shore they are visible and some feel eyesores. Shipping interests say shipping lanes are compromised by the wind turbines. The problem was that no wind farms were allowed any further out than 3-4 miles. The federal government has now agreed to open up deep ocean waters, and by new federal government rules this will create vast areas of space to place wind turbines. The area that they have agreed to let companies develop is the outer continental shelf, it extends to the edge of U.S. territory 230 miles out. These wind farms would not obstruct views, or interfere with any other activity.

The U.S. Department of the Interior, the agency that is responsible for the new rules planned to finalize to rules by the end of 2008. They will lease plots of the shelf to developers of wind farms and other renewable energy projects. These other projects include ocean current and wave-harvesting technologies. States along the northeast coast where 80 percent of the population of the U.S. lives, have decided to providing some of the funding for these wind farms in the hope that they will have some of the energy from the farms transmitted into state grids and help meet renewable energy requirements. The Ocean Renewable Energy Coalition's founder Sean O'Neill thinks the leases may be too expensive and the environmental review process too extensive. Other groups are saying that there are too many barriers to overcome, and they want to know are these waters really open?

Opening the shelf is probably the only way to have offshore wind projects for the U.S. There have been problems in the past trying to get something like this done. Most proposed wind projects in state waters can be seen from shore, and there's potential interference with shipping lanes. Wind turbines in these conditions have to have a smaller design and this leads to a reduction in the anticipated amount of electricity causing profits to fall. In addition no one seemed to know who had control, before the new federal government rules. As a result there is not a single offshore wind turbine operating in the U.S. today.

Nearly 80 percent of the population of the U.S. live in coastal states. In the heavily populated areas there is simply no room for wind turbine farms. Wind turbines located on the continental shelf will generate 1000 gigawatts of electricity. That number is more than the electrical capacity of the entire U.S. The U.S. is in the rear with regard to offshore wind turbines, Europe has more than 2 dozen wind parks in their waters.

New designs have to be developed for deep water wind turbines. At shallow depths it is a simple matter to drive a pole into the floor of the sea, this is called a monopile. The concept is like having to drive piles for reinforced concrete construction. Obviously they cannot have the deepwater turbines without new designs that will take the depth of the water into consideration.

Engineers and researchers are trying new designs like underwater tripods and lattice type structures called jackets. German developer Alpha Ventus is in the next few months going to build a dozen turbines with tripod and lattice structures in deep water. The leading developer in this type of technology are the engineering staff for Beatrice Wind Farm in the North Sea close to Scotland, with turbines 138 feet deep and over 15 miles from shore.

Engineers have determined these designs would be good for depths of 200 feet. The option they have for deeper water is floating structures used by the oil industry. The platforms would not be exactly the same as the oil industry has experience in using, however they would be very similar. Private developers in Europe say they are working on prototypes for this model. Otherwise this technology could take up to a decade to to get up and running.

The cost of deepwater windturbine installation is twice that of wind turbines on land. The industry here in the U.S. is being very careful, they don't want to fail because of fear that would hamper or completely stop further offshore construction of wind turbine farms.


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