Abstract: Methods, systems, and apparatus by which steam and/or hot water generated using solar energy may be utilized to generate electricity or work are disclosed herein. A method in one instance may involve driving a first turbine using a fluid having energy obtained from a main energy source other than solar energy, and using solar energy-generated hot water and/or steam as an auxiliary energy input to drive the first turbine. An apparatus in one instance may include (1) a first turbine in fluid communication with and driven by a fluid heated by a main energy source other than solar energy in fluid communication with (2) a solar steam and/or hot water generator that utilizes solar energy to generate hot water and/or steam or other working fluid as an auxiliary energy input source for the first turbine.

Abstract: A combined cycle power plant includes a first generator driven by a gas turbine for generating electricity. The combined cycle power plant further includes a heat recovery steam generator disposed to receive exhaust gas from the gas turbine. The heat recovery steam generator includes an evaporator having tubes receptive to water flow therethrough. The tubes are disposed to be exposed to the exhaust gas, such that a flow of the exhaust gas passes around the tubes transfers heat from the exhaust gas to the tubes and thereby the water flowing through the tubes sufficient for the water to evaporate into steam. The tubes each having an outer surface with a plurality of deformations formed therein sufficient to introduce turbulence in the flow of the exhaust gas for enhancing heat transfer from the exhaust gas to the tubes.

Abstract: A gas turbine system includes a compressor, an expander, a combustor disposed between the compressor and the expander, a boiler disposed between the compressor and the expander, a conduit including chargeable air and in thermal communication with the boiler and an external free heat source coupled to the boiler.

Abstract: A combined cycle power plant in which a gas turbine engine generates power, a heat recovery steam generator (HRSG) produces steam from high energy fluids produced from the generation of power in the gas turbine engine and a steam turbine engine generates additional power from the steam produced in the HRSG. The combined cycle power plant includes a heating element fluidly interposed between the steam turbine engine and the HRSG to heat fluid output from the steam turbine engine, which is to be fed to the HRSG and a control system to control an amount the fluid output from the steam turbine engine is heated by the heating element based on differences between HRSG and ambient temperatures.

Abstract: A hybrid solar power plant includes a first circuit including a first flow medium and a second circuit including a second flow medium. The first circuit includes at least one solar collector to transfer collected solar heat to the first flow medium. The first circuit includes at least one first fluid/second fluid heat exchanger to exchange heat from the first flow medium in the first circuit to the second flow medium in the second circuit. The second circuit is preferably a water/steam circuit. The second circuit includes at least one steam turbine for generating electricity out of steam. The first circuit further includes a heat source for generating a flow of heating gas. The heat source serves as the auxiliary energy. A gas/first fluid heat exchanger is provided for transferring heat from the flow of heating gas to the first flow medium in the first circuit.

Abstract: According to one embodiment, there is provided a power plant operating method. The method includes calculating by a turbine output calculating unit a turbine output based on an exponential value of a steam pressure measured at an arbitrary point downstream from the repeater, calculating by a power generator output calculating unit a power generator output generated by the power generator, detecting by an output deviation detecting unit a deviation between the turbine output and the power generator output, detecting by a power load unbalance detecting unit power load unbalance when the deviation exceeds a preset value, and outputting by a control unit a rapid close command to regulator valves of the steam turbine when the power load unbalance is detected.

Abstract: A method is disclosed for operating a gas turbine power plant having a gas turbine, a heat recovery steam generator and an flue gas splitter which splits flue gases into a first flue gas flow for recirculation into an inlet flow of the gas turbine and into a second flue gas flow for discharge to an environment. An oxygen-depleted gas can be used in an open cooling system for cooling hot gas parts of the gas turbine. A split compressor intake can be provided for separate feed of recirculated flue gas and fresh air into a compressor intake. Compressor blades can include a separating band which blocks intermixing of recirculated flue gas and fresh air during compression.

Abstract: A method for assembling a combined cycle power generation system includes coupling a gas turbine in flow communication with a heat recovery steam generator (HRSG). The method also includes coupling a steam turbine in flow communication with the HRSG via at least one steam conduit. The method further includes coupling at least one heating element to a portion of the at least one steam conduit. The method also includes operatively coupling at least one controller to the at least one heating element. The method further includes programming the at least one controller to vary a rate of temperature change in the portion of the at least one steam conduit.

Abstract: Ambient air is compressed into a compressed ambient gas flow and delivered to a turbine combustor. At least one of an exhaust port, a bypass conduit, or an extraction conduit is opened to vent the power plant. A turbine shaft is rotated at an ignition speed and a fuel stream is delivered to the turbine combustor for mixing with the compressed ambient gas flow to form a combustible mixture. The combustible mixture is burned and forms a recirculated gas flow that drives the turbine. The recirculated gas flow is recirculated using the recirculation loop. The turbine is operated at a target operating speed and then reaches substantially stoichiometric combustion. At least a portion of the recirculated gas flow is extracted using an extraction conduit that is fluidly connected to the turbine compressor.

Abstract: An application and process that incorporates an external heat source to increase the temperature of the airstream entering a compressor section of a combustion turbine. The application and process may perform an anti-icing operation that may not require an Inlet Bleed Heat system (IBH) to operate. Additionally, the application and process may perform an anti-icing operation that may allow for the IGV angle to remain nearly constant. The application and process may increase the output and efficiency of a combustion turbine operating at partload by delaying IBH operation and delaying the closing IGVs.

Abstract: A method and system for co-production of electric power, fuel, and chemicals in which a synthesis gas at a first pressure is expanded using a stand-alone mechanical expander or a partial oxidation gas turbine, simultaneously producing electric power and an expanded synthesis gas at a second pressure after which the expanded synthesis gas is converted to a fuel and/or a chemical.

Abstract: A power plant is provided including a steam power plant and/or a combined cycle power plant. A water steam cycle of the plant includes two steam turbine arrangements; the first turbine arrangement includes steam turbines with at least two pressure levels and a second turbine arrangement having at least one back pressure turbine configured to expand steam to the supply pressure of a CO2 capture system. A method for operating the plant includes operating the first steam turbine arrangement to produce power during all steady state operating points of the steam cycle and at least a part of the second steam turbine arrangement is bypassed to the system and/or is operated to produce power and to release low-pressure steam to the system when the system is in operation. Both steam turbine arrangements are operated using all available steam to produce power when the system is not in operation.

Abstract: A method of assembling a steam turbine power system with a coolant source is provided. The method includes providing a first steam turbine train including a first high pressure turbine assembly, a first low pressure turbine assembly coupled in flow communication with the first high pressure turbine assembly, and a first condenser coupled in flow communication with the first low pressure turbine assembly. The method also includes providing a second steam turbine train including a second high pressure turbine assembly, a second low pressure turbine assembly coupled in flow communication with the second high pressure turbine assembly, and a second condenser coupled in flow communication with the second low pressure turbine assembly.

Abstract: A power generation system that comprises a first power generator; a first turbine operable to drive the first power generator; a vaporizer operable to vaporize a working fluid, wherein the vaporized working fluid turns the first turbine; and a condenser operable to condense the vaporized working fluid exiting the first turbine, wherein the condenser is coupled to the vaporizer such that the condensed working fluid is vaporized in the vaporizer. The power generation system also comprises a second power generator; a second turbine operable to burn a fuel to drive the second power generator; a switch to selectively operate the second turbine independently of the first turbine; and a heat exchanger coupled to the second turbine to receive flue gas from the second turbine when operated, wherein heat is transferred in the heat exchanger from the flue gas to the vaporized working fluid after the vaporized working fluid exits the vaporizer and prior to the vaporized working fluid entering the first turbine.

Abstract: An exhaust gas waste heat recovery heat exchanger includes a housing having a working fluid inlet, a working fluid outlet, an exhaust inlet, and an exhaust outlet, an exhaust flow path extending through the housing between the exhaust inlet and the exhaust outlet, and a working fluid flow path extending through the housing between the working fluid inlet and the working fluid outlet and having a first portion and a second portion. A flow of working fluid along the first portion of the working fluid flow path can be substantially counter to a flow of exhaust along the exhaust flow path, and the flow of working fluid along the second portion of the working fluid flow path can be substantially parallel to the flow of exhaust along the exhaust flow path.

Abstract: A waste heat recovery system is provided. The waste heat recovery system includes a gas separation apparatus that includes a chamber and at least one membrane positioned within the chamber. The gas separation apparatus is configured to produce a retentate that includes at least a combustible gas and a permeate that includes at least a waste gas, wherein the waste gas includes at least a noncombustible gas. Moreover, the waste heat recovery system includes a burner that is coupled to the gas separation apparatus, wherein the burner is configured to receive the permeate and to combust the permeate such that heat is generated from the permeate. Further, a heat recovery steam generator is coupled to the burner and configured to recover heat generated by the burner.

Abstract: An ORC system configured to limit temperature of a working fluid below a threshold temperature is provided. The ORC system includes a heat source configured to convey a waste heat fluid. The ORC system also includes a heat exchanger coupled to the heat source. The heat exchanger includes an evaporator configured to receive the waste heat fluid from the heat source and vaporize the working fluid, wherein the evaporator is further configured to allow heat exchange between the waste heat fluid and the vaporized working fluid at an elevated temperature and further produce an evaporator outlet flow including a lower temperature waste heat fluid.

Abstract: A method of monitoring a power generation system that includes a steam turbine that is coupled to a gas turbine engine. The method includes calculating, by a control system, a gas turbine engine power output that is based at least in part on a predefined power generation system power output and a predefined steam turbine power output. The power generation system is operated to generate a power output that is approximately equal to the predefined power generation system power output. A signal indicative of a sensed operating power output of the gas turbine engine is transmitted from a sensor to the control system. A condition of the steam turbine is determined based at least in part on the sensed operating gas turbine engine power output and the calculated gas turbine engine power output.

Abstract: A method is provided for operating a gas turbine power plant with exhaust gas recirculation, in which, based upon the operating state of the gas turbine a setpoint concentration of at least one constituent in an exhaust gas flow and/or in the intake flow of the gas turbine after adding the recirculated exhaust gases is determined. The actual concentration of the at least one constituent in the exhaust gas flow and/or in the intake flow is measured and a control element for controlling the recirculation flow is controlled based upon the setpoint/actual deviation. Also provided is a gas turbine power plant with exhaust gas recirculation and includes a controller, in which a setpoint concentration of at least one constituent in an exhaust gas flow or in the intake flow of the gas turbine is determined, and a measuring instrument for measuring the actual concentration of the at least one constituent.

Abstract: A system and method of maintaining an optimal temperature range for a catalyst section in a HRSG comprising placing a portion of the exhaust stream in a heat exchanger and superheater, diverting a second portion around the heat exchanger and superheater, combining the two portions and contacting the two portions with a catalyst section. Alternatively, a system of heat exchangers are employed to address the fluctuating exhaust temperature caused by the intermittent use of the duct burners.

Abstract: The present invention is a gas turbine combined cycle power plant which generates electricity by fueling a gas turbine with crude oil or heavy oil and which is provided with a vacuum distillation unit which distills and extracts a light oil fraction from crude oil or heavy oil by keeping the interior thereof in an environment which lowers a boiling point of crude oil or heavy oil, and the vacuum distillation unit is provided with heaters which heat distillation materials by using low pressure steam and medium pressure steam generated in a gas turbine combined cycle.

Abstract: A method involves operating a combined-cycle power plant (10), which has a gas turbine (11) with a compressor (12) and a turbine (13), a heat recovery steam generator (17) which is connected downstream to the gas turbine (11) and is for producing steam in a water/steam cycle, and also at least one once-through cooler (21), through which flows compressed air which is compressed in the compressor (12) and intended for cooling the gas turbine (11), and, cooling down, converts feed-water (24) which is fed from the heat recovery steam generator (17) into steam, and discharges the steam to the heat recovery steam generator (17). The combined-cycle power plant is switched between a first operating mode, in which only the gas turbine cycle is used for power generation, and a second operating mode, in which the gas turbine cycle and the water/steam cycle are used for power generation.

Abstract: A combined-cycle system includes a compressor, a gas turbine, a steam turbine, and an electric generator, which are coupled to the same shaft. A method of controlling the system envisages detecting a current compression ratio of the compressor, calculating a normalized compression ratio on the basis of the current compression ratio, and determining a load condition of the gas turbine on the basis of the normalized compression ratio. Moreover, a setpoint is selected, for at least one operating quantity of the gas turbine, and regulating signals are applied to actuators of the gas turbine so that the operating quantity of the gas turbine tends to reach the setpoint.

Abstract: A power generation system having an exhaust gas attemperating device and method for controlling a temperature of exhaust gases is provided. The exhaust gas attemperating device includes a first conduit and a venturi member. The first conduit is configured to receive at least a portion of exhaust gases from a gas turbine. The venturi member is disposed in the first conduit and defines a flow path therethrough for receiving the exhaust gases in the first conduit. The first conduit and the venturi member have an aperture extending therethrough communicating with the flow path, such that the exhaust gases flowing through the flow path draws ambient air through the aperture into the flow path for reducing a temperature of the exhaust gases flowing through the first conduit.

Abstract: A combined cycle power plant includes a gas turbine, a condensing stage, a steam turbine, and a heat recovery steam generator (HRSG). The HRSG is configured to generate steam for driving the steam turbine in response to heat transferred from exhaust gas received from the gas turbine at a first temperature and to transmit the exhaust gas to the condensing turbine at a second temperature that is lower than the first temperature.

Abstract: A steam cycle power plant includes a gas turbine, a gas turbine intercooler, a steam turbine, and a heat recovery steam generator (HRSG). The gas turbine intercooler recovers unused heat generated via the gas turbine and transfers substantially all of the recovered heat for generating extra steam for driving the steam turbine.

Abstract: A power plant for burning a fuel in a low pressure combustion chamber to produce electrical power. A first compressor supplies compressed air through a first heat exchanger to add heat to the compressed air. The heated compressed air is passed through a first turbine to drive a first electric generator. The first turbine outlet is passed through a second heat exchanger in series with the first heat exchanger to further heat the compressed air. The compressed air is then passed through a second turbine to drive a second electric generator and produce electric power. The outlet from the second turbine is passed through a first combustor to produce the hot gas flow through the second heat exchanger. The outlet from the second heat exchanger is passed through a second combustor before passing through the first heat exchanger. The outlet from the first heat exchanger is passed through a heat recovery steam generator to generate steam to drive another turbine and another generator.

Abstract: A system and assemblies for pre-heating fuel in a combined cycle power plant are provided. A fuel supply system includes a water heater assembly configured to heat a flow of water using progressively higher grade heat from a multi-stage heat exchanger arrangement. The fuel supply system also includes a fuel heater that includes a first flow path coupled in flow communication with a fuel flow path wherein the fuel heater includes a second flow path coupled in flow communication with a flow path for the flow of water. The fuel heater is configured to transfer heat from the flow of water to the flow of fuel.

Abstract: A combined cycle power plant includes a gas turbine having a first compressor, a second compressor downstream of the first compressor, and a regenerative heat exchanger between the first and second compressors. A steam generator is downstream of the gas turbine and receives exhaust from the gas turbine. A closed loop cooling system through the regenerative heat exchanger and the steam generator transfers heat from the regenerative heat exchanger to the steam generator. A method for operating a combined cycle power plant includes compressing a working fluid in a compressor and cooling the compressed working fluid with a regenerative heat exchanger so as to create a cooled compressed working fluid. The method further includes transferring heat from the regenerative heat exchanger to a steam generator.

Abstract: Contemplated plants integrate regeneration of a freeze point depressant with LNG regasification and a power cycle. Most preferably, the plant is a combined cycle plant in which heat for reboiling the regenerator is provided by the steam cycle, and in which LNG refrigeration content is used to condense steam from the regenerator and to further subcool intake air for a combustion turbine.

Abstract: The invention relates in particular to a method for converting thermal energy from carbonaceous raw materials into mechanical work, having at least one first (4) and one second (6) device for storing and releasing thermal energy connected to least intermittently alternatingly in a turbine branch (T) having a gas turbine (8) connected downstream thereof, comprising the steps of: a) combusting a gas in a gas combustor (2); b) passing the smoke gases (3) arising in the gas combustor (2) through a device (4, 6) for storing thermal energy; and c) feeding the hot air released by at least one device (4, 6) into the gas turbine (8), wherein the hot air (7) released by the gas turbine (8) is fed to at least one heat exchanger ( ) connected downstream of the gas turbine (8).

Abstract: Systems and a method for controlling a temperature of an exhaust gas stack are provided. The system includes a first heat exchanger positioned upstream in exhaust gas flow communication to an exhaust gas inlet to the stack, a second heat exchanger positioned upstream in exhaust gas flow communication to the first heat exchanger, and a water side conduit configured to direct a flow of relatively hot water from the second heat exchanger to the first heat exchanger such that a temperature of a flow of exhaust gas flowing through the first exchanger is maintained within a predetermined range.

Abstract: A gas turbine is driven by a combustion gas produced when BFG compressed by a gas compressor and air compressed by a compressor are burned in a combustor. Steam is generated from a waste heat boiler by utilization of heat of an exhaust gas from the gas turbine, and a steam turbine is driven by this steam. An electric generator generates electricity upon driving of the turbines. A condensing heat exchanger is disposed in an air intake duct, and part of steam from the waste heat boiler flows through the heat exchanger to heat intake air. The amount of steam that flows through the heat exchanger is adjusted by adjusting the degree of opening of a steam control valve by a control device. By so doing, the ignition performance of the gas turbine in a BFG-fired gas turbine combined cycle plant is enhanced even in an extremely cold district.

Abstract: An external steam turbine main steam startup control valve bypass loop is provided to facilitate a full pressure combined cycle rapid response/fast start powerplant. The main steam startup bypass control loop particularly includes a main steam startup bypass control valve, which allows for the implementation of high efficiency, low pressure drop main steam control valve that otherwise would not be able to handle the severe throttling duty during a full pressure steam turbine startup and enhances the controllability of the steam turbine allowing for the high fidelity controls necessary to minimize steam turbine rotor stresses.

Abstract: A system comprises a first heat recovery steam generator (HRSG) operative to receive steam from a source of steam and output water to the source of steam, a second HRSG operative to receive steam from the source of steam and output water to the source of steam, a first water flow control valve operative to regulate a flow of the water output from the first HRSG to the source of steam, and a second water flow control valve operative to regulate a flow of the water output from the second HRSG to the source of steam.

Abstract: A combined cycle power plant includes a gas turbomachine, a steam turbomachine operatively connected to the gas turbomachine, a heat recovery steam generator (HRSG) operatively connected to the gas turbomachine and the steam turbomachine, and a cooling system fluidly connected to the gas turbomachine. The cooling system is configured and disposed to pass a coolant through the gas turbomachine to absorb heat. A condensate system is fluidly connected to the steam turbine and the HRSG. The condensate system is configured and disposed to deliver a steam condensate from the steam turbine to the HRSG. A heat exchange member is fluidly connected to the cooling system and the condensate system. The heat exchange member is configured and disposed to transfer heat entrained in the coolant to the steam condensate.

Abstract: Exemplary embodiments are disclosed that utilize waste heat from one or more aeroderivative turbines to provide backup thermal energy for a parabolic trough concentrating solar power (CSP) plant.

Abstract: A heat recovery steam generator (HRSG) is coupled to a gas turbine engine that discharges a flow of exhaust gases including oxides of nitrogen (NOx) The HRSG includes a steam-based heating element for heating the exhaust gases, and at least one NOx reduction element coupled downstream from the at least one steam-based heating element and configured to facilitate reducing an amount of NOx in the exhaust gases that are channeled into the at least one NOx reduction element.

Abstract: Methods and systems for the generation of electrical energy through the combination of steam flows produced from different fuel sources. Steam produced from processing of a biomass fuel source is combined with steam produced from the processing of natural gas or fossil fuel and routed through a steam turbine generator to produce electrical energy. The steam is preferably reheated after partial processing in the steam turbine generator and then recirculated for further processing in the steam turbine generators. Following extraction of all available energy from the steam, the steam is condensed to water, the feedwater is then reheated and pumped to the boilers of both energy sources for conversion into steam.

Abstract: This invention presents improved combustion methods, systems, engines and apparatus utilizing H2, O2 and H2O as fuel, thereby providing environmentally friendly combustion products, as well as improved fuel and energy management methods, systems, engines and apparatus. The Water Combustion Technology; WCT, is based upon water (H2O) chemistry, more specifically H2O combustion chemistry and thermodynamics. WCT does not use any hydrocarbon fuel source, rather the WCT uses H2 preferably with O2 and secondarily with air. The WCT significantly improves the thermodynamics of combustion, thereby significantly improving the efficacy of combustion, utilizing the first and second laws of thermodynamics. The WCT preferably controls combustion temperature with H2O and secondarily with air in the combustion chamber. The WCT preferably recycles exhaust gases as fuel converted from water.

Abstract: A power plant includes a gas turbine unit adapted to feed whose flue gases into a boiler of a steam turbine unit, to be then diverted into a recirculated flow and discharged flow. The recirculated flow is mixed with fresh air forming a mixture that is fed into a gas turbine unit compressor. The discharged flow is fed into a CO2 capture unit that is an amine based or chilled ammonia based CO2 capture unit.

Abstract: A system and method for removing at least carbon from a fuel/air mixture prior to injection of the fuel/air mixture into a combustion system is disclosed. The system fully integrates the combined cycle power plant with carbon scrubbing of the fuel/air mixture to increase overall cycle efficiency while capturing carbon from the cycle. A portion of the compressed air source generated by the gas turbine compressor is provided to a premixer where it is mixed with a natural gas to form a fuel/air mixture. The fuel/air mixture passes through a catalytic partial oxidation (CPOX) reactor, which utilizes a precious metal to partially oxidize the hydrocarbons into carbon monoxide. The mixture passes through a shift reactor to complete generation of carbon dioxide and raise hydrogen yield of the fuel/air mixture. Carbon constituents are then removed from the mixture by a separator.

Abstract: A method involved operating a combined-cycle power plant (10), which has a gas turbine (11) with a compressor (12) and a turbine (13), a heat recovery steam generator (17) which is connected downstream to the gas turbine (11) and is for producing steam in a water/steam cycle, and also at least one once-through cooler (21), through which flows compressed air which is compressed in the compressor (12) and intended for cooling the gas turbine (11), and, cooling down, converts feed-water (24) which is fed from the heat recovery steam generator (17) into steam, and discharges the steam to the heat recovery steam generator (17). Making the operation more flexible is achieved, without lowering the load of the gas turbine (11), by the combined-cycle power plant (10) being switched between a first operating mode, in which only the gas turbine cycle is used for power generation, and a second operating mode, in which the gas turbine cycle and the water/steam cycle are used for power generation.

Abstract: Systems and methods for integrating heat exchanger elements of HRSG systems with gas turbine exhaust diffusers are provided in the disclosed embodiments. The systems and methods may include integrating heat exchanger elements, such as steam pipes, with various components of an exhaust diffuser. For example, the heat exchanger elements may be integrated with inlet turning vanes, exhaust frame struts, exit guide vanes, associated support structures, and other components of the exhaust diffuser. In addition, the heat exchanger elements may be integrated with multiple components of a single exhaust diffuser. Moreover, the heat exchanger elements may be integrated with the components of the exhaust diffuser within an airfoil, which may encompass both the heat exchanger elements and the individual component of the exhaust diffuser. The use of airfoils may help ensure certain aerodynamic properties of the heated exhaust gas flowing across the exhaust diffuser components.

Abstract: A split heat recovery steam generator (HRSG) arrangement including a first HRSG coupled to a turbine and thereby receptive of a portion of the exhaust gases to deliver the portion of the exhaust gases to a compressor, a second HRSG coupled to the turbine and thereby receptive of a remaining portion of the exhaust gases, which includes an NOx catalyst and a CO catalyst sequentially disposed therein to remove NOx and CO from the exhaust gases and an air injection apparatus to inject air into the second HRSG between the NOx catalyst and the CO catalyst to facilitate CO consumption at the CO catalyst.

Abstract: A method for assembling a fuel supply system for use with a power generation system. The method includes coupling a fuel heater to a fuel source for heating a fuel. A first heating assembly is coupled to the fuel heater for heating a first flow of water channeled to the fuel heater. A heat recovery steam generator assembly is coupled to the fuel heater for channeling a second flow of heated water to the fuel heater. A valve assembly is coupled between the first heating assembly, the heat recovery steam generator assembly, and the fuel heater to enable a flow of heated water from the first heating assembly and the heat recovery steam generator assembly to be selectively channeled to the fuel heater.

Abstract: A combined cycle power plant includes a gas turbine having a first compressor, a second compressor downstream of the first compressor, and a regenerative heat exchanger between the first and second compressors. A steam generator is downstream of the gas turbine and receives exhaust from the gas turbine. A closed loop cooling system through the regenerative heat exchanger and the steam generator transfers heat from the regenerative heat exchanger to the steam generator. A method for operating a combined cycle power plant includes compressing a working fluid in a compressor and cooling the compressed working fluid with a regenerative heat exchanger so as to create a cooled compressed working fluid. The method further includes transferring heat from the regenerative heat exchanger to a steam generator.

Abstract: A combined cycle power plant includes a gas turbine having a first compressor, a second compressor downstream of the first compressor, and a regenerative heat exchanger between the first and second compressors. A steam generator is downstream of the gas turbine and receives exhaust from the gas turbine. A closed loop cooling system through the regenerative heat exchanger and the steam generator transfers heat from the regenerative heat exchanger to the steam generator. A method for operating a combined cycle power plant includes compressing a working fluid in a compressor and cooling the compressed working fluid with a regenerative heat exchanger so as to create a cooled compressed working fluid. The method further includes transferring heat from the regenerative heat exchanger to a steam generator.

Abstract: A system and method for controlling the temperature of a fuel gas. The system and method includes mixing an intermediate pressure feedwater stream from the heat recovery steam generator with a high pressure feedwater stream from the heat recovery steam generator, then using that mixture to heat the fuel gas mixture. The system and method may provide for improved control over the Modified Wobbe Index of the fuel gas, which may allow for greater variation in the composition of the fuel gas.

Abstract: Disclosed is an optimized approach of using bleed-off of compressed air flow from a gas turbine compressor in a combined-cycle power plant and performance heating to augment plant performance. In one embodiment, a diverted portion of a by-product off gas and the bleed-off of compressed air flow are fired heated to produce a high temperature flue gas that is used to performance heat a pressurized mixture of fuel prior to being supplied to the gas turbine combustor.