Significant research efforts are currently centered on developing advanced gas turbine systems for electric power generation applications. Gas-steam combined cycles are often used to obtain a high efficiency power plant. Two innovative gas turbine technologies have recently been proposed for combined cycle applications. Two gas-steam combined cycles using thermodynamic analysis are presented: a combined cycle with three pressure levels with reheat heat recovery boiler is used with two different gas turbine technologies (high pressure ratio and reheat against "H" technology). This analysis constitutes a comparison not only between two different constructive solutions but also between two different gas turbine (GT) techniques (reheat and GT steam cooling) and technologies (a consolidated and an advanced gas turbine technology) applied to a combined cycle, (C) 2000 Elsevier Science Ltd. All rights reserved.