Heat recovery steam generator for a combined cycle power plant

A combined cycle power plant comprising:

• a gas turbomachine system including a compressor and a gas turbine, the gas turbine extracting work from first gases at a first temperature;
• a steam turbomachine system including at least one steam turbine having a high pressure portion and an intermediate pressure portion, the at least one steam turbine extracting work from second gases at a second temperature;
• and
• a heat recovery steam generator having a main housing fluidly connected to the gas turbomachine, the heat recovery steam generator including a reheat member arranged outside the main housing, the reheat member having an interior chamber fluidly connected to the high pressure portion of the steam turbine through a steam conduit and to the intermediate pressure portion of the steam turbine through an outlet member, a plurality of sealed heat pipes having a partial vacuum, at least a portion of the plurality of sealed heat pipes extend within the main housing in fluid communication with the gases at the first temperature, the plurality of heat pipes also being in fluid communication with the gases at the second temperature within the interior chamber, wherein the plurality of sealed heat pipes absorb heat from the first gases at the first temperature and pass the heat into the second gases at the second temperature to raise the temperature of the second gases to a third temperature, the second gases at the third temperature being passed back through the main housing and to the intermediate portion of the steam turbine through the outlet member.