Chemical recuperation of heat is the most considerable method of increasing the efficiency of combined-cycle plants, but plants with chemical recuperation are not in application yet. In this paper, the causes of this phenomenon have been examined and the thermodynamic basis of using chemical recuperation of heat has been given. The energy efficiency of a combined cycle plant with chemical recuperation has reached 80-90% and more and it increases with lower reforming pressure. Additionally, chemical recuperation has raised the amount of gas fuel used in energy and chemical industries and has decreased the amount of waste carbon dioxide ejected into the environment by nearly 20%. The energy efficiency of a power plant with chemical recuperation must be calculated with registration of the methane which does not undergo a reaction in the reformer. (C) 2003 Published by Elsevier Ltd.