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.

The present invention relates to an arrangement comprising a waste heat recovery system (WHR-system) and a method for controlling the arrangement. The arrangement comprises an expansion tank having a constant inner volume, first cooling means configured to cool the working fluid in the condenser and a control unit configured to control the first cooling means such that the working fluid is cooled to a desired condensation temperature in the condenser during operation of the WHR system. The arrangement comprises further a sub-cooler arranged in a position downstream of the condenser and second cooling means configured to cool the working fluid in the sub-cooler, and that the control unit is configured to control the second cooling means such that the working fluid receives a determined subcooling in the sub-cooler during operation of the WHR system.

The heat cycle facility includes: a first vaporizer that vaporizes a first liquid heating medium by combusting fuel; a first motive power generator that generates motive power by using as a drive fluid a first gas heating medium obtained at the first vaporizer; a condenser that condenses the first gas heating medium discharged from the first motive power generator by heat-exchanging the first gas heating medium for a second liquid heating medium; a circulator that pressurizes the first liquid heating medium obtained at the condenser and supplies the pressurized first liquid heating medium to the first vaporizer; a second vaporizer that produces gaseous ammonia by heat-exchanging the second liquid heating medium for liquid ammonia; and a supplier that supplies the liquid ammonia to the second vaporizer.

The heat cycle facility includes: a first vaporizer that vaporizes a first liquid heating medium by combusting fuel; a first motive power generator that generates motive power by using as a drive fluid a first gas heating medium obtained at the first vaporizer; a condenser that condenses the first gas heating medium discharged from the first motive power generator by heat-exchanging the first gas heating medium for a second liquid heating medium; a circulator that pressurizes the first liquid heating medium obtained at the condenser and supplies the pressurized first liquid heating medium to the first vaporizer; a second vaporizer that produces gaseous ammonia by heat-exchanging the second liquid heating medium for liquid ammonia; and a supplier that supplies the liquid ammonia to the second vaporizer.

A complete bearing-sealed root vacuum pump system capable of promoting vacuum ability of a condenser of a power plant provides a complete bearing-sealed structure. All chambers are isolated effectively so that liquid cannot flow there between and thus not to destroy the root vacuum pump. Therefore, the lifetime of the root vacuum pump is prolonged. The heat exchangers are arranged between the root vacuum pumps and the front stage pump so as to return the condensed water. The condenser vacuum is improved and thus the power generation efficiency is promoted, and power consumption is lowered. As a result a large power plant can save several thousand tons of coals per year.

An energy storage plant includes a casing for the storage of a working fluid other than atmospheric air, in a gaseous phase and in equilibrium of pressure with the atmosphere; a tank for the storage of said working fluid in a liquid or supercritical phase with a temperature close to the critical temperature; wherein said critical temperature is close to the ambient temperature. The plant is configured to carry out a closed thermodynamic cyclic transformation, first in one direction in a charge configuration and then in the opposite direction in a discharge configuration, between said casing and said tank; wherein in the charge configuration the plant stores heat and pressure and in the discharge configuration generates energy.

An energy storage plant includes a casing for the storage of a working fluid other than atmospheric air, in a gaseous phase and in equilibrium of pressure with the atmosphere; a tank for the storage of said working fluid in a liquid or supercritical phase with a temperature close to the critical temperature; wherein said critical temperature is close to the ambient temperature. The plant is configured to carry out a closed thermodynamic cyclic transformation, first in one direction in a charge configuration and then in the opposite direction in a discharge configuration, between said casing and said tank; wherein in the charge configuration the plant stores heat and pressure and in the discharge configuration generates energy.

A cascade organic Rankine cycle plant comprising a hot source, at least a first high temperature organic Rankine cycle and a second low temperature organic Rankine cycle, said cycles comprising at least one preheater, at least one vaporizer, at least one turbine, at least one condenser, wherein the hot source first supplies a vaporizer of the high temperature cycle, then the vaporizer of the low temperature cycle and finally it is divided into two flows which supply a first preheater of the high temperature cycle and a preheater of the low temperature cycle. The first high-temperature organic Rankine cycle comprises a further vaporizer operating at an intermediate pressure between the vaporizer pressure of the high temperature cycle and the vaporizer pressure of the low temperature cycle.

A power plant comprises supplies of hydrogen fuel, oxygen fuel and water, a boiler comprising a burner for combusting hydrogen and oxygen to produce heat, combustion products and low/intermediate-pressure steam and a first heat exchanger configured to heat water to generate high-pressure steam, and a steam turbine comprising a first turbine configured to be driven only with the high-pressure steam to provide input to a first electrical generator and a second turbine configured to be driven by low/intermediate-pressure steam from the boiler. A method of operating a steam plant comprises combusting hydrogen fuel in a boiler to produce combustion products and LP/IP steam, turning a turbine with the combustion products, condensing water from the combustion products in a condenser, heating water from the condenser in a heat exchanger within the boiler to produce HP steam and turning a turbine with the steam from the first heat exchanger.

A power plant comprises supplies of hydrogen fuel, oxygen fuel and water, a boiler comprising a burner for combusting hydrogen and oxygen to produce heat, combustion products and low/intermediate-pressure steam and a first heat exchanger configured to heat water to generate high-pressure steam, and a steam turbine comprising a first turbine configured to be driven only with the high-pressure steam to provide input to a first electrical generator and a second turbine configured to be driven by low/intermediate-pressure steam from the boiler. A method of operating a steam plant comprises combusting hydrogen fuel in a boiler to produce combustion products and LP/IP steam, turning a turbine with the combustion products, condensing water from the combustion products in a condenser, heating water from the condenser in a heat exchanger within the boiler to produce HP steam and turning a turbine with the steam from the first heat exchanger.