ATLANTIC WIND CONNECTION:
How it Works
The Atlantic Wind Connection project will connect multiple offshore wind farms that will be built in the federally-designated Wind Energy Areas ten to twelve miles off the Mid-Atlantic coast to the strongest parts of the existing terrestrial transmission grid.
Using the most advanced transmission technology available today
, the Atlantic Wind Connection will be able to move offshore wind electricity from where it is generated to where it is needed and where it is most valuable.
And when the winds are calm and the wind farm output drops, the line will be used to move conventional energy resources efficiently from places where there is surplus power to places where the demand, and the price, is high.
In addition, the grid along the coast is generally weak, and building a high-capacity cable paralleling the coast will strengthen the grid and make it more reliable.
The system will consist of several major components::
- Offshore converter platforms
- Offshore submarine transmission cables
- Onshore underground transmission cables
- Onshore converter stations
The offshore converter platforms
are positioned in the federally-designated Wind Energy Areas where wind farms can easily and inexpensively connect. At each platform location an offshore steel foundation is installed that will support a high-voltage direct-current (HVDC) converter. The converter platform converts the high-voltage alternating current (AC) output from a wind farm sub-station to HVDC, using a semi-conductor based technology known as insulated gate bipolar transistors (IGBTs).
The converter platform directs the HVDC output to the subsea cable system
, which consists of a bundle of three cables:
- Positive 320KV HVDC submarine power cable,
- Negative 320KV HVDC submarine power cable,
- Submarine fiber optic cable for system control and data communications.
is the preferred way to transmit large amounts of energy long distances through submarine and subterranean cables because the cables experience low power losses and the technology permits greater controllability of power flows.
The power on the Atlantic Wind Connection network is actively controlled and directed to the north, central or south where and when it is most needed.
At the land-based point of interconnection with the terrestrial grid, an onshore converter station
converts the power from HVDC back to the appropriate AC voltage and frequency for delivery into the terrestrial grid.
The system is so flexible that when the winds are calm and there is little offshore wind power production, power from conventional generating plants can also be directed to the north, central or south on the offshore network to other land-based points of interconnection where the power is needed.