In accordance with at least on aspect of this disclosure, there is provided a hydrogen fuel system for aircraft. The hydrogen fuel system includes a gas turbine engine and a fuel feed conduit. The fuel feed conduit is defined at least in part by, in fluid series, a liquid hydrogen tank fluidly connected to a combustor of the gas turbine engine, a liquid hydrogen pump to drive fuel to the combustor of the gas turbine engine, an evaporator, and an electric heat source in thermal communication with the evaporator to add heat into a flow of hydrogen passing through the evaporator. In embodiments, the electric energy source associated with the electric heat source to power the electric heat source.

In accordance with at least on aspect of this disclosure, there is provided a hydrogen fuel system for aircraft. The hydrogen fuel system includes a gas turbine engine and a fuel feed conduit. The fuel feed conduit is defined at least in part by, in fluid series, a liquid hydrogen tank fluidly connected to a combustor of the gas turbine engine, a liquid hydrogen pump to drive fuel to the combustor of the gas turbine engine, an evaporator, and an electric heat source in thermal communication with the evaporator to add heat into a flow of hydrogen passing through the evaporator. In embodiments, the electric energy source associated with the electric heat source to power the electric heat source.

A method for managing the offtake of power produced by an auxiliary power unit of an aircraft. The method comprises a step of calculating a maximum capacity for offtake of mechanical power that the auxiliary power unit can provide to the aircraft, a step of determining an actual offtake of mechanical power taken off by a first mechanical power offtake system of the auxiliary power unit, a step of comparing the maximum capacity for offtake of mechanical power and the actual offtake of mechanical power, a step of optimizing the offtake of mechanical power which step, based on the comparison of the maximum capacity for offtake of mechanical power and the actual offtake of mechanical power, determines at least one corrective action. A device for managing the offtake of power produced by an auxiliary power unit of an aircraft and an aircraft including such a device are provided.

A power production facility comprises a power plant that combusts fuel to produce energy for generating electricity and exhaust gas, an emissions capture unit to receive the exhaust gas to remove pollutants, a fuel cell to generate electricity via reaction of constituents and provide byproduct heat to operate the emissions capture unit, and an electrolyzer to generate constituents for the fuel cell from water byproduct received from the fuel cell resulting from the reaction process. A method of generating power with an emissions capture unit comprises providing a hybrid power plant configured to generate hydrogen gas and oxygen gas with an electrolyzer from a water input using an electrical input, generate electricity, heat and the water input with a fuel cell from the hydrogen gas and oxygen gas of the electrolyzer, and capture emissions from exhaust gas with an emissions capture unit using the heat from the fuel cell.

A power production facility comprises a power plant that combusts fuel to produce energy for generating electricity and exhaust gas, an emissions capture unit to receive the exhaust gas to remove pollutants, a fuel cell to generate electricity via reaction of constituents and provide byproduct heat to operate the emissions capture unit, and an electrolyzer to generate constituents for the fuel cell from water byproduct received from the fuel cell resulting from the reaction process. A method of generating power with an emissions capture unit comprises providing a hybrid power plant configured to generate hydrogen gas and oxygen gas with an electrolyzer from a water input using an electrical input, generate electricity, heat and the water input with a fuel cell from the hydrogen gas and oxygen gas of the electrolyzer, and capture emissions from exhaust gas with an emissions capture unit using the heat from the fuel cell.

A pressurized air supply system supplies, to a pressurization object device, flowing air that includes at least one of compressed air, which is generated by compressing air supplied from an air supply source, or discharged air from a turbocharger compressor forming a turbocharger. The compressor is controlled such that a saturated steam temperature of the flowing air supplied from the air supply source to the pressurization object device is lower than a temperature in the pressurization object device, at startup.

A power source for an aircraft having a gas turbine engine, including: an electrical connection assembly; a fuel cell assembly integrated into the gas turbine engine, electrically coupled to the connection assembly and configured to provide a first power output; and an electric machine coupled to the gas turbine engine, electrically coupled to the connection assembly and configured to provide a second power output, wherein both the first power output from the fuel cell assembly and the second power output from the electric machine are provided to the connection assembly during operating of the gas turbine engine and wherein the connection assembly is electrically coupled to an aircraft electrical load.

A power production facility comprises a power plant that combusts fuel to produce energy for generating electricity and exhaust gas, an emissions capture unit to receive the exhaust gas to remove pollutants, a fuel cell to generate electricity via reaction of constituents and provide byproduct heat to operate the emissions capture unit, and an electrolyzer to generate constituents for the fuel cell from water byproduct received from the fuel cell resulting from the reaction process. A method of generating power with an emissions capture unit comprises providing a hybrid power plant configured to generate hydrogen gas and oxygen gas with an electrolyzer from a water input using an electrical input, generate electricity, heat and the water input with a fuel cell from the hydrogen gas and oxygen gas of the electrolyzer, and capture emissions from exhaust gas with an emissions capture unit using the heat from the fuel cell.

A power production facility comprises a power plant that combusts fuel to produce energy for generating electricity and exhaust gas, an emissions capture unit to receive the exhaust gas to remove pollutants, a fuel cell to generate electricity via reaction of constituents and provide byproduct heat to operate the emissions capture unit, and an electrolyzer to generate constituents for the fuel cell from water byproduct received from the fuel cell resulting from the reaction process. A method of generating power with an emissions capture unit comprises providing a hybrid power plant configured to generate hydrogen gas and oxygen gas with an electrolyzer from a water input using an electrical input, generate electricity, heat and the water input with a fuel cell from the hydrogen gas and oxygen gas of the electrolyzer, and capture emissions from exhaust gas with an emissions capture unit using the heat from the fuel cell.

The invention provides a CO.sub.2 turbine power generation system that can be easily prevented from reaching an overspeed condition. A CO.sub.2 turbine power generation system of an embodiment includes a CO.sub.2 medium shutoff valve installed in a medium flow path between a regenerative heat exchanger and a combustor. When load rejection is to be performed, the CO.sub.2 medium shutoff valve closes to shut off the supply of the medium from the regenerative heat exchanger to the combustor.