Houston-headquartered Friede & Goldman Ltd (F&G), long a leader in jack-up technology, has partnered with Rotterdam-headquartered Tetrahedron B.V. to offer an interesting new wind turbine installation solution for the U.S. offshore wind market.
Called NewWindShape, it is not based on the use of a large conventional WTIV (wind turbine installation vessel) designed to transport turbine components as well as install them. Instead, the turbines are installed using a relatively small F&G designed jack-up, fitted with a Tetrahedron leg-encircling crane.
Turbine components are brought to the jack-up using standard ocean barges as feeder vessels and, as in other feedering based systems, the jack-up does not need to be Jones Act compliant.
A key component of the system is the Tetrahedron model 65 crane. Able to achieves lifting heights of 200 meters above the still water level and with a 20 MW turbine installation capability, the crane has a tetrahedron shape. This shape allows the crane to take the increased side loads often seen with afloat load transfers.
Tetrahedron has also developed the Smart Hoist system, said to offer “unparalleled” lifting speeds. In addition, a “rigging-on-deck” principle is used to eliminate the need for a heavy tool to clamp on the top-flange of a tower segment.
“That is important, because it eliminates the mating process of the heavy flange clamp onto the top of a swinging tower,” say the partners. “With Tetrahedron’s side load stability, Smart Hoist, and ‘rigging-on-deck’ principles, the NewWindShape can complete turbine component transfers without expensive active motion compensating systems.”