Highly efficient electricity generation through a hybrid molten carbonate fuel cell-closed loop gas turbine plant

Fuel cells have been revealed to be very attractive power generation systems, promising highly efficient electricity generation and very low environmental impact. With the high-temperature fuel cells still in embryonic infancy, the very high energetic efficiency can be further increased by their integration into hybrid cycles. While a wide variety of potential bottoming technologies for the exploitation of the high temperature exhaust gases waste heat is available, a lot of research effort is needed to determine the optimal integration of well established technologies with these very novel conversion devices. The aim of this work is to provide a contribution to selecting promising plants for the electricity generation of the future, and it constitutes an attempt to optimize the working parameters and estimation of the performances. A basic plant configuration and its main working parameters have been determined, including the plant performance, the stream thermodynamic and chemical properties and the component temperatures. A modified plant configuration has been found, allowing the optimal exploitation of the waste heat streams for internal heat regeneration. Different bottoming cycles have been considered, and a parametric analysis has been performed with the aim of performance comparisons. The most promising solution has been determined, and its performance evaluated. (C) 2001 Published by Elsevier Science Ltd.