A fuel cell ship includes a fuel cell compartment in which a fuel cell is installed, a tank compartment in which a fuel tank is installed, a fuel supply pipe through which fuel is supplied from the fuel tank to the fuel cell, and a control unit. The fuel supply pipe includes at least two shutoff valves. Fuel gas detectors that detect a fuel gas being in a gaseous state of the fuel are each installed in the compartments. If at least one of the fuel gas detectors detects that a concentration of the fuel gas is equal to or greater than a predetermined standard value, the control unit controls to close a shutoff valve in a compartment out of the tank compartment and the fuel cell compartment, where the fuel gas detector having detected the concentration equal to or greater than the standard value is installed.

An exemplary fuel cell ship is a fuel cell ship for propelling a hull by using electric power supplied by a fuel cell that generates electric power through an electrochemical reaction of fuel, and includes at least one compartment including an emission source of the fuel, and a vent pipe through which the fuel in the compartment is released to outside of the hull. A release port of the vent pipe is located at a position higher than a cabin or a bridge provided on the hull.

A fuel cell ship includes a storage battery compartment installed with a storage battery that supplies, to a propulsion device, electric power different from electric power by a fuel cell. The storage battery compartment is provided between a deck and a ship bottom portion of a hull.

An exemplary fuel cell ship is a fuel cell ship for propelling a hull by using electric power supplied from a fuel cell that generates electric power through an electrochemical reaction of fuel, and includes a tank compartment installed therein with a fuel tank that stores the fuel. The tank compartment is provided below a deck of the hull and provided separately from other compartments.

An exemplary fuel cell ship is a fuel cell ship for propelling a hull by using electric power supplied from a fuel cell that generates electric power through an electrochemical reaction of fuel, and includes a plurality of compartments including an emission source of the fuel, in which the plurality of compartments include a tank compartment installed therein with a fuel tank that stores the fuel and a fuel cell compartment installed therein with the fuel cell. The tank compartment and the fuel cell compartment are each sealed except for a ventilation port through which the inside of the compartment is ventilated.

A fuel cell ship includes a cooling system that cools a fuel cell. The cooling system includes a cooling medium tank that accommodates a cooling medium, a cooling medium circulation pipe that circulates the cooling medium between the fuel cell and the cooling medium tank, a cooling tank internal gas detector installed in the cooling medium tank, a cooling tank internal gas discharge pipe connected to the cooling medium tank, and a cooling tank internal gas discharge valve installed in the cooling tank internal gas discharge pipe. The fuel cell ship includes a control unit that controls opening and closing of the cooling tank internal gas discharge valve. The control unit opens the cooling tank internal gas discharge valve when the cooling tank internal gas detector detects that the concentration of the fuel gas in the cooling medium tank is equal to or greater than a specified value determined in advance.

A ventilator for exhausting gas from an exhaust port, by utilizing wind or relative wind around and through the ventilator to create a reduced pressure zone at an open exhaust port. Tapered intermediate portions extend from the opposite ends of a centrally located throat portion within a body of the ventilator to a pair of opposite mouths through which gas can flow out through the ventilator from the exhaust port. Each mouth of the ventilator has an opening with an area significantly larger than the area of a flow path within the throat portion. The throat portion may be of constant internal cross-sectional area over its entire length.

A ventilator for exhausting gas from an exhaust port, by utilizing wind or relative wind around and through the ventilator to create a reduced pressure zone at an open exhaust port. Tapered intermediate portions extend from the opposite ends of a centrally located throat portion within a body of the ventilator to a pair of opposite mouths through which gas can flow out through the ventilator from the exhaust port. Each mouth of the ventilator has an opening with an area significantly larger than the area of a flow path within the throat portion. The throat portion may be of constant internal cross-sectional area over its entire length.

A watercraft and method for operating the watercraft, wherein the watercraft includes an electrical system that is present in a space that has an atmosphere that differs from air, where the space is formable by a pressure hull, where the atmosphere contains, for example, an inert gas, and where the space having the electrical system is filled with the atmosphere.

A watercraft and method for operating the watercraft, wherein the watercraft includes an electrical system that is present in a space that has an atmosphere that differs from air, where the space is formable by a pressure hull, where the atmosphere contains, for example, an inert gas, and where the space having the electrical system is filled with the atmosphere.