A power plant comprising - an arrangement of a steam turbine (410, 420) and a generator (415, 425) for producing electric energy using steam, - a boiler having • a furnace, • a flue gas duct for leading flue gases from the furnace, • a drum, • superheater piping (260, 270) for superheating steam and conveying steam from the drum to the steam turbine, • feed water piping (210, 220, 230, 240, 310, 312, 320, 322, 330, 332) for feeding water and/or steam into the drum, • a last economizer that is in the direction of flow of the feed water in the feed water piping (210, 220, 230, 240, 310, 312, 320, 322, 330, 332) the last economizer forming a part of the feed water piping, and is arranged at such a location that no other economizer is arranged in the direction of flow of feed water in between the last economizer and the drum in the feed water piping. - an afterheater • configured to heat water and/or steam running in the feed water piping (210, 220, 230, 240, 310, 312, 320, 322, 330, 332) by using heating steam and • arranged, in the direction of flow of the feed water in the feed water piping (210, 220, 230, 240, 310, 312, 320, 322, 330, 332) and along the feed water piping (210, 220, 230, 240, 310, 312, 320, 322, 330, 332), upstream from the drum and downstream from the last economizer, and - a pipeline (610, 610a, 610b, 610c) for conveying the heating steam to the afterheater, wherein - the pipeline (610, 610a, 610b, 610c) is configured to convey the heating steam to the afterheater from at least one of • a location of the superheater piping (260, 270), the location being arranged, in the direction of flow of steam in the superheater piping, downstream from at least a phase of the steam turbine, • the steam turbine, and • a steam net configured to receive steam from another boiler. - an arrangement of a steam turbine (410, 420) and a generator (415, 425) for producing electric energy using steam, - a boiler having • a furnace, • a flue gas duct for leading flue gases from the furnace, • a drum, • superheater piping (260, 270) for superheating steam and conveying steam from the drum to the steam turbine, • feed water piping (210, 220, 230, 240, 310, 312, 320, 322, 330, 332) for feeding water and/or steam into the drum, • a last economizer that is in the direction of flow of the feed water in the feed water piping (210, 220, 230, 240, 310, 312, 320, 322, 330, 332) the last economizer forming a part of the feed water piping, and is arranged at such a location that no other economizer is arranged in the direction of flow of feed water in between the last economizer and the drum in the feed water piping. • a furnace, • a flue gas duct for leading flue gases from the furnace, • a drum, • superheater piping (260, 270) for superheating steam and conveying steam from the drum to the steam turbine, • feed water piping (210, 220, 230, 240, 310, 312, 320, 322, 330, 332) for feeding water and/or steam into the drum, • a last economizer that is in the direction of flow of the feed water in the feed water piping (210, 220, 230, 240, 310, 312, 320, 322, 330, 332) the last economizer forming a part of the feed water piping, and is arranged at such a location that no other economizer is arranged in the direction of flow of feed water in between the last economizer and the drum in the feed water piping. - an afterheater • configured to heat water and/or steam running in the feed water piping (210, 220, 230, 240, 310, 312, 320, 322, 330, 332) by using heating steam and • arranged, in the direction of flow of the feed water in the feed water piping (210, 220, 230, 240, 310, 312, 320, 322, 330, 332) and along the feed water piping (210, 220, 230, 240, 310, 312, 320, 322, 330, 332), upstream from the drum and downstream from the last economizer, and • configured to heat water and/or steam running in the feed water piping (210, 220, 230, 240, 310, 312, 320, 322, 330, 332) by using heating steam and • arranged, in the direction of flow of the feed water in the feed water piping (210, 220, 230, 240, 310, 312, 320, 322, 330, 332) and along the feed water piping (210, 220, 230, 240, 310, 312, 320, 322, 330, 332), upstream from the drum and downstream from the last economizer, and - a pipeline (610, 610a, 610b, 610c) for conveying the heating steam to the afterheater, wherein - the pipeline (610, 610a, 610b, 610c) is configured to convey the heating steam to the afterheater from at least one of • a location of the superheater piping (260, 270), the location being arranged, in the direction of flow of steam in the superheater piping, downstream from at least a phase of the steam turbine, • the steam turbine, and • a steam net configured to receive steam from another boiler. • a location of the superheater piping (260, 270), the location being arranged, in the direction of flow of steam in the superheater piping, downstream from at least a phase of the steam turbine, • the steam turbine, and • a steam net configured to receive steam from another boiler.