System for transferring an object from a ship to an offshore structure

A method for transferring an object between a ship and an offshore structure, the method comprising:

• providing the offshore structure with an electrically operated hoisting mechanism responsive to a control unit, the control unit configured to receive vertical displacement information from a first device mounted on the offshore structure and receive vertical displacement information from a second device mounted on the ship, and the control unit receiving power from a stand-alone power supply mounted on the offshore structure or a cable adapted to connect to a power source on the ship, wherein the offshore structure comprises an electrical emergency power supply cable attachable to an external power source;
• configuring the control unit to, in the absence of vertical displacement information from the first device, continue to operate using the vertical displacement information from the second device;
• and
• suspending the object using the hoist, wherein the control unit uses the vertical displacement information to determine to move the object in synchronicity with a vertical position of the ship relative to the offshore structure when within a predetermined distance to a deck of the ship to avoid collision of the object with the ship.

An offshore structure, comprising:

• an electrically operated hoisting mechanism responsive to a control unit, wherein an object is suspended from the hoisting mechanism and the control unit moves the object up or down;
• the control unit comprising:
• a receiver configured to receive vertical displacement information relative to a ship docked against the offshore structure, the vertical displacement information provided by a first device mounted on the offshore structure and by a second device mounted on the ship;
• a motor configured to receive power from a power supply mounted on the offshore structure or a cable adapted to connect to a power source on the ship;
• and
• wherein the control unit is configured to move the object in synchronicity with a vertical position of the ship when within a predetermined distance to a deck of the ship to avoid collision of the object with the ship, wherein, in the absence of vertical displacement information from the first device, the control unit is configured to continue to operate the hoisting mechanism using the vertical displacement information from the second device;
• wherein the offshore structure has no ladder, and
• wherein the offshore structure comprises an electrical emergency power supply cable attachable to an external power source.