Performance analysis of a heavy duty combined cycle power plant burning various syngas fuels D. Sa ´ nchez*, R. Chacartegui, J.M. Mun ˜ oz, A. Mun ˜oz, T. Sa ´ nchez Escuela Te ´cnica Superior de Ingenieros, Camino de los descubrimientos s/n, 41092 Sevilla, Spain article info Article history: Received 8 July 2009 Accepted 23 October 2009 Available online 14 November 2009 Keywords: Syngas Combined cycle Performance abstract This paper presents a performance analysis of state of the art combined cycles power plants burning a number of syngas fuels. The first part of the analysis focuses on the effect of gas composition on the rated performance of the plant drawing two main conclusions. First, higher pressure ratio and lower firing temperature are found at turbine inlet. Second, the pressure at which fuel is supplied to the gas turbine plays an essential role in the power capacity of the engine. With respect to the steam cycle, no major effects are appreciated except for very low LHV fuels. In the second part of the work, the annual performance of the engine subjected to a typical load profile and real ambient and market conditions is studied. Differences in total incomes are appreciated depending on fuel composition and the concern about carbon emissions is highlighted. ª 2009 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved. 1. Introduction During the last decade, burning hydrogen in heavy duty gas turbines has been considered one of the best ways to accomplish a sustainable power system in the near term. Industry and academia have worked closely to try and develop new concepts and products to make it possible. However, hydrogen is not a real primary energy source, like for instance coal or natural gas, since it is not available as a raw fuel. Instead, it is found bounded to carbon or oxygen under the form of hydrocarbons of different composition and molecular weight, water or, in much smaller quantities, biomass. Hence, the final objective of burning hydrogen in gas turbines based power plants, either simple or combined cycle, requires that hydrogen be produced, transported and, in many cases, purified and separated from other by-products of the production process. This is the case of, for example, carbon monoxide, sulphur and nitrogen oxides. Developing efficient and environmentally friendly processes to produce hydrogen in big quantities is therefore the first step in the road to having power plants burning this fuel. Hydrogen rich fuels being available, the second step of the process is related to gas turbines engineering since this is the equipment where these fuels are to be burnt. Among all its components, fuel injectors and combustor are those that need to be modified more [1,2], with a lot of work to be done at the turbine as well. Gas turbine manufacturers are committed in the development of engines capable of burning hydrogen rich fuel as efficiently and reliably as possible and most of them are running specific programmes for it: Siemens [3,4], General Electric [5,6], Mitsubishi Heavy Industries [7] and Alstom [8]. Finally, a third step to be developed in parallel to the previous one is system integration. Power plant performance analyses including thermodynamic, economic and environ- mental considerations are mandatory so as to determine the costs, benefits and drawbacks of burning these unconven- tional fuels. Once the impact of fuel composition is evaluated and the roadmap for improved performance is set up, gas * Corresponding author. Tel.: þ34 954 48 64 88; fax: þ34 954 48 72 43. E-mail addresses: davidsanchez@esi.us.es (D. Sa ´ nchez), ricardo@esi.us.es (R. Chacartegui), jme@esi.us.es (J.M. Mun ˜ oz), ambl@esi.us. es (A. Mun ˜ oz), tmsl@esi.us.es (T. Sa ´ nchez). Available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/he 0360-3199/$ – see front matter ª 2009 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ijhydene.2009.10.080 international journal of hydrogen energy 35 (2010) 337–345