A combined cycle power plant and method for operating a combined power plant with stack energy control are presented. The combined cycle power plant includes a gas turbine, a heat recovery steam generator including a plurality of heating surfaces, and a steam turbine. The heating surfaces may be partially bypassed to reduce steam production in the heat recovery steam generator during power plant startup. Less energy may be extracted from exhaust gas of the gas turbine. More energy may be dumped through an exhaust stack. The steam turbine may start without restriction of a gas turbine load during power plant startup. The steam turbine may start without increasing a size of an air cooled condenser while maintaining a higher load of a gas turbine during power plant startup.

Provided is a solar thermal power generation facility that includes: a compressor; a medium heating heat receiver that receives sunlight and heats a compressed medium from the compressor; a turbine that is driven by the compressed medium heated by the medium heating heat receiver; a power generator that generates electric power by driving of the turbine; and a tower that supports these components. The compressor, the turbine, and the power generator are formed as arranged devices. A plurality of the arranged devices are aligned in a vertical direction.

A method includes determining, via a processor, a commanded temperature rate for a component of a steam turbine system. The method further includes determining, via the processor, a measured temperature rate for the component of the steam turbine system. The method additionally includes determining, via the processor, a variable multiplier based at least in part on the commanded temperature rate and the measured temperature rate. The method also includes deriving, via the processor, a multiplied temperature rate command by applying the variable multiplier to the commanded temperature rate.

The purpose of the present invention is to maintain the intake pressure of a water supply pump at an operable pressure. A boiler is provided with: condensate pumps (a condensate pump and an auxiliary condensate pump); a branch line that causes water delivered by the condensate pumps to branch; a drum (a low-pressure drum) that is connected to one (a low-pressure branch line) of two lines into which the branch line branches; and a water supply pump that is connected to the other (a high-pressure branch line) of the two lines into which the branching line branches and that pumps water to an evaporator (a high-pressure evaporator). The boiler is additionally provided with pressure applying means that guides a portion of the water in the drum to the water supply pump side when the intake pressure on the inlet side of the water supply pump has become lower than a predetermined pressure.

A gas turbine plant including a gas turbine and a compressor is provided with a steam turbine plant including a steam turbine and a condenser, and, an exhaust heat recovery boiler. Steam from the exhaust heat recovery boiler is directly flown to the condenser of the steam turbine plant through a bypass control valve. A pressure sensor detects pressure in a turbine bypass system. A controller outputs, based on a set value from an input device and a process value from the pressure sensor, an open level instruction value to the control value so as to make the process value consistent with the set value in a predetermined sampling cycle. A corrector corrects the set value from the input device in a direction in which the open level instruction value decreases when the open level instruction value from the controller becomes a value that substantially fully opens the control valve.

A combined power generation system includes a gas turbine, a heat recovery steam generator (HRSG) configured to heat feedwater using combustion gases discharged from the gas turbine and having a high-pressure section, a medium-pressure section, and a low-pressure section having different pressure levels, an ammonia decomposer decomposing ammonia with the combustion gases discharged from the gas turbine, a first exhaust gas line through which the exhaust gases discharged from the gas turbine are transferred to the HRSG, a second exhaust gas line through which the exhaust gases discharged from the gas turbine are transferred to the ammonia decomposer, a third exhaust gas line through which the exhaust gases discharged from the ammonia decomposer are transferred to the HRSG, and a decomposed gas transfer tube connecting the ammonia decomposer and the combustor to transfer decomposed gases generated with the decomposition of ammonia to the combustor.

A combined cycle power plant (CCPP) is provided. The CCPP includes a gas turbine that has a compressor section, a combustion section, and a turbine section. The CCPP further includes a heat recovery steam generator (HRSG) that has a first economizer. The HRSG receives a flow of exhaust gas from the turbine section. The HRSG further includes a fuel heating system that has a fuel supply line and a high temperature heat exchanger disposed in thermal communication on the fuel supply line. The fuel supply line is fluidly coupled to the combustion section. The high temperature heat exchanger is fluidly coupled to the first economizer such that the high temperature heat exchanger receives water from the first economizer. The CCPP further includes a feedwater pump that is fluidly coupled to the high temperature heat exchanger.

Described herein are technologies of a heat engine that transforms a low-level temperature differential between a heat source and a heat sink into useful electrical power. One heat engine includes a hydro-electric turbine, a steam source configurable to generate steam from a hot water source, a condenser, and a slug intake bend in a first pipe coupled between the steam source and the condenser. The slug intake bend is configurable to receive a slug of water from a cold water source. The steam from the hot water source pushes the slug of water up a vertical distance to the condenser. The condenser is configurable to receive the slug of water and the steam and provide liquid water from the slug of water and steam to power the hydro-electric turbine.

There is provided a combined cycle power plant in which a high-pressure steam turbine and an intermediate-pressure steam turbine can operate in a state where amounts of thermal effect thereof are close to a limit value, and capable of reducing start-up time. A combined cycle power plant includes: an exhaust heat recovery boiler that includes a high-pressure superheater which superheats steam for a high-pressure steam turbine, and a reheater which reheats steam for an intermediate-pressure steam turbine; bypass pipes through which steam bypasses the high-pressure superheater and the reheater; bypass valves that regulate flow rates of steam which flows through the bypass pipes; and a bypass controller that controls the bypass valves such that a difference between thermal effect-amount margins of the turbines is decreased.

A heat exchange system includes: a gas line through which a gas to be cooled flows; a first heat exchanger disposed in the gas line and configured to cool the gas through heat exchange with a refrigerant; a refrigerant introduction line for introducing the refrigerant into the first heat exchanger; a refrigerant discharge line for discharging the refrigerant after cooling the gas from the first heat exchanger; a recirculation line for recirculating at least a part of the refrigerant flowing through the refrigerant discharge line into the refrigerant introduction line; and a flow-rate adjustment unit for adjusting a flow rate of the refrigerant flowing through the recirculation line so that a temperature of the refrigerant introduced into the first heat exchanger from the refrigerant introduction line is not lower than a threshold.