A power generation sailing ship has a sail provided on a deck, a water turbine connected to a front end of a shaft passing through a bow part outer hull and extending forward, a power generator disposed in a front body of the sailing ship and connected to a rear end of the shaft, and an energy storage device for directly storing electric energy generated by the power generator or converting the electric energy into energy of a substance and storing the substance.

A power system for a marine vessel comprises an engine and a controllable pitch thruster drivably coupled to the engine. A speed of the controllable pitch thruster various with a speed of the engine. A control unit receives a thrust command value indicating a thrust required from controllable pitch thruster. The control unit determines a current speed of the controllable pitch thruster and calculates a pitch of the controllable pitch thruster that produces thrust in accordance with the thrust command value at the current speed of the controllable pitch thruster. The power system allows for operating the engine at variable speeds to allow for a reduction of the engine speed under partial load conditions.

A fuel tank arrangement in a marine vessel has a tank container, a first fuel line having a first fuel line port opening into the tank container so as to provide a flow path exclusively for a first fuel, a second fuel line having a second fuel line port opening into the tank container so as to provide a flow path exclusively for a second fuel. The first fuel line port and/or the second fuel line port is provided with a plug or alike to close the flow path from the tank container into the fuel line.

Various implementations include propulsion systems and related methods of operation. In one implementation, a system includes: an internal combustion engine, wherein the internal combustion engine has a combustion chamber for burning a fossil fuel, an electrolysis chamber for producing hydrogen gas and oxygen gas, a turbocharger, a supply line connecting a compressor of the turbocharger to the combustion chamber, the supply line designed to convey a gas mixture including at least a part of the hydrogen gas and the oxygen gas to the combustion chamber, a gasification tank with volatile organic compounds received therein, and an air supply for supplying compressed air into the gasification tank, wherein the gas mixture, which is guided via the supply line to the combustion chamber, also includes gasified organic compounds from the gasification tank.

A self-propelling watercraft system is provided. The watercraft has a base with a plurality of sidewalls extending from the base to form a cockpit. The base also has a recess, where a pump can detachably connect to the hull within the recess. The pump has an intake valve on a first end and a nozzle on a second end that is opposite the first end. The intake valve can intake water. The nozzle can jettison water received in the pump from the intake valve and agitate water surrounding the nozzle.

A gas processing system according to an embodiment of the present invention includes a heater which is configured to increase a temperature of liquefied gas compulsorily vaporized by a forcing vaporizer before the liquefied gas is joined with Boil Off Gas (BOG) compressed by a BOG compressor.

A marine vessel includes at least one gas fuel consumer is arranged at a first horizontal level in the vessel, and at least one gas tank for the gas fuel consumer is arranged at a second horizontal level in the vessel, which second horizontal level is different from the first horizontal level. The vessel is provided with a fluid passing shaft for providing a confined vertically extending shaft between a gas consumer at a first horizontal level in the vessel and at least one gas fuel tank arranged at a second horizontal level in the vessel.

A ship includes: a boil-off gas heat exchanger installed on a downstream of a storage tank and heat-exchanges a compressed boil-off gas (a first fluid) by a boil-off gas discharged from the storage tank as a refrigerant, to cool the boil-off gas; a compressor installed on a downstream of the boil-off gas heat exchanger and compresses a part of the boil-off gas discharged from the storage tank; an extra compressor installed on a downstream of the boil-off gas heat exchanger and in parallel with the compressor and compresses the other part of the boil-off gas discharged from the storage tank; a refrigerant heat exchanger which additionally cools the first fluid which is cooled by the boil-off gas heat exchanger; and a refrigerant decompressing device which expands a second fluid, which is sent to the refrigerant heat exchanger, and then sends the second fluid back to the refrigerant heat exchanger.

A ship includes: a boil-off gas heat exchanger which is installed on a downstream of a storage tank and heat-exchanges a compressed boil-off gas (a first fluid) by a boil-off gas discharged from the storage tank as a refrigerant to cool the boil-off gas; a compressor installed on a downstream of the boil-off gas heat exchanger and compresses a part of the boil-off gas from the storage tank; an extra compressor which is installed on a downstream of the boil-off gas heat exchanger and in parallel with the compressor and compresses the other part of the boil-off gas from the storage tank; a refrigerant heat exchanger which additionally cools the first fluid; and a refrigerant decompressing device which expands a second fluid, which is sent to the refrigerant heat exchanger, and then sends the second fluid back to the refrigerant heat exchanger.

A vessel propulsion apparatus includes a propulsive force generator including a duct and a propeller. The duct includes a stator. The propeller includes a rim that includes a rotor disposed at a position facing the stator, and a blade on an inner side in a radial direction of the rim. The vessel propulsion apparatus further includes a steering shaft that turnably supports the duct, a motor controller that rotationally drives an electric motor including the stator and the propeller in forward and reverse rotation directions, a turning mechanism that turns the duct in a full turning angle range including a range of 180 degrees, and a turning angle range limiter that limits a turning angle range of the turning mechanism to a reduced turning angle range narrower than the full turning angle range, and when a predetermined limitation cancellation condition is met, cancels the limitation and allows turning in a turning angle range wider than the reduced turning angle range.