Control of low pressure recoup air in a gas turbine engine disposed in a gas turbine enclosure with low pressure recoup air piping coupled to a gas turbine combustion exhaust and gas turbine engine enclosure is disclosed. A first valve of the piping controls a flow of the recoup air to the gas turbine combustion exhaust. A second valve of the piping diverts the recoup air to the enclosure for eventual flow to the air intake. A controller controls the flow of the recoup air from the piping to the exhaust and/or the enclosure as a function of ambient and air intake temperature measurements, and a predetermined temperature requirement having an ambient temperature constraint and an air intake temperature differential constraint.

A power plant having a gas turbine and having a heat recovery steam generator installed downstream of the gas turbine in the direction of flow of an exhaust gas, wherein the heat recovery steam generator includes heating surfaces of a high pressure section, of an intermediate pressure section and of a low pressure section, wherein an exhaust gas recirculation line branches from the heat recovery steam generator downstream of an evaporator in the flow direction of an exhaust gas in the high pressure section and opens again into the heat recovery steam generator upstream of the heating surfaces. A blower is arranged in the exhaust gas recirculation line, with a steam feed opening into the exhaust gas recirculation line downstream of the blower in the direction of flow of a recirculated exhaust gas. A method operates a power plant of this kind.

A power plant having a gas turbine and having a heat recovery steam generator installed downstream of the gas turbine in the direction of flow of an exhaust gas, wherein the heat recovery steam generator includes heating surfaces of a high pressure section, of an intermediate pressure section and of a low pressure section, wherein an exhaust gas recirculation line branches from the heat recovery steam generator downstream of an evaporator in the flow direction of an exhaust gas in the high pressure section and opens again into the heat recovery steam generator upstream of the heating surfaces. A blower is arranged in the exhaust gas recirculation line, with a steam feed opening into the exhaust gas recirculation line downstream of the blower in the direction of flow of a recirculated exhaust gas. A method operates a power plant of this kind.

In a cryogenic combined cycle power plant electric power drives a cryogenic refrigerator to store energy by cooling air to a liquid state for storage within tanks, followed by subsequent release of the stored energy by first pressurizing the liquid air, then regasifying the liquid air and raising the temperature of the regasified air at least in part with heat exhausted from a combustion turbine, and then expanding the heated regasified air through a hot gas expander to generate power. The expanded regasified air exhausted from the expander may be used to cool and make denser the inlet air to the combustion turbine. The combustion turbine exhaust gases may be used to drive an organic Rankine bottoming cycle. An alternative source of heat such as thermal storage, for example, may be used in place of or in addition to the combustion turbine.

In a cryogenic combined cycle power plant electric power drives a cryogenic refrigerator to store energy by cooling air to a liquid state for storage within tanks, followed by subsequent release of the stored energy by first pressurizing the liquid air, then regasifying the liquid air and raising the temperature of the regasified air at least in part with heat exhausted from a combustion turbine, and then expanding the heated regasified air through a hot gas expander to generate power. The expanded regasified air exhausted from the expander may be used to cool and make denser the inlet air to the combustion turbine. The combustion turbine exhaust gases may be used to drive an organic Rankine bottoming cycle. An alternative source of heat such as thermal storage, for example, may be used in place of or in addition to the combustion turbine.

There are described methods and systems for operating an aircraft having two or more engines. One method comprises operating the two or more engines of the aircraft in an asymmetric operating regime, wherein a first of the engines is in an active mode to provide motive power to the aircraft and a second of the engines is in a standby mode to provide substantially no motive power to the aircraft; governing the first engine in the active mode using a first governing logic; and governing the second engine in the standby mode using a second governing logic, the second governing logic based on a target compressor speed and variable geometry mechanism (VGM) settings that are adjusted using trim values dependent on at least one parameter of the second engine in the standby mode.

There are described methods and systems for operating an aircraft having two or more engines. One method comprises operating the two or more engines of the aircraft in an asymmetric operating regime, wherein a first of the engines is in an active mode to provide motive power to the aircraft and a second of the engines is in a standby mode to provide substantially no motive power to the aircraft; governing the first engine in the active mode using a first governing logic; and governing the second engine in the standby mode using a second governing logic, the second governing logic based on a target compressor speed and variable geometry mechanism (VGM) settings that are adjusted using trim values dependent on at least one parameter of the second engine in the standby mode.

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 system includes a gas turbine engine configured to combust an oxidant and a fuel to generate an exhaust gas, a catalyst bed configured to treat a portion of the exhaust gas from the gas turbine engine to generate a treated exhaust gas, a differential temperature monitor configured to monitor a differential temperature between a first temperature of the portion of exhaust gas upstream of the catalyst bed and a second temperature of the treated exhaust gas downstream of the catalyst bed, and an oxidant-to-fuel ratio system configured to adjust a parameter to maintain an efficacy of the catalyst bed based at least in part on the differential temperature in order to maintain a target equivalence ratio.