ABB, the power and automation technology group, has won an order worth around $700 million, from the German transmission grid operator, transpower, to supply an 800-megawatt (MW) power link that will connect more offshore wind farms in the DolWin1cluster, located in the North Sea to the mainland German grid.

ABB will deploy its innovative and environmentally friendly HVDC Light (high-voltage direct current) transmission technology to transmit power from the 400 MW Borkum West II wind farm and other wind farms to be developed nearby. The wind farms will be connected to an offshore HVDC converter station which will transmit electricity to the onshore HVDC station at Dörpen, on the northwest coast of Germany via 165 km of underwater and underground DC cables. The Dörpen/West converter station will in turn feed AC power to the mainland grid.

This is the largest power transmission order in ABB's history. At 320-kilovolt this will be the highest voltage level of extruded cable ever used for HVDC.

ABB will be responsible for system engineering, including design, supply and installation of the offshore platform, the offshore and onshore converter stations, and will also supply and install the sea and land cable systems. ABB is uniquely positioned with in-house manufacturing capability of converter stations,cables and semiconductors.

“Offshore wind power is becoming a key source of large-scale renewable energy and is making a vital contribution to the effort of lowering environmental impact,” said Peter Leupp, head of ABB’s Power Systems division. ”ABB has state-of-the-art transmission technologies for integrating renewable energy sources efficiently and ensuring grid reliability and stability.”

HVDC Light transmission systems offer numerous environmental benefits, such as neutral electromagnetic fields, oil-free cables and compact converter stations. It is an ideal solution for connecting remote offshore wind farms to mainland networks, overcoming distance limitations and grid constraints, while ensuring robust performance and minimal electrical losses.

Scheduled to be operational in 2013, this network of offshore wind farms is expected to avoid three million tons of carbon dioxide emissions per year by replacing fossil-fuel based generation. Germany currently meets about eight percent of its electricity requirements with wind power and expects to double that by 2020.

This is the second HVDC Light offshore wind connection supplied by ABB in Germany, the first being the BorWin1 project, the most remote offshore wind farm in the world.