Innovative solar augmentation of gas turbine combined cycle plants

Abstract

The objective of this paper is to offer а concept for innovative hybridization of gas turbine combined cycle plant and solar power system. This conceptual plant is named as Solar Assisted Combined Cycle, as the solar energy is indirectly involved in power generation. The proposed solar hybridization can be accomplished in two ways. The first solar assisted option introduces mechanical chiller for a complete cooling of gas turbine inlet air. Such of cooling is commonly used to increase the power output of gas turbines during hot days of the year. This mechanical chiller is powered with electricity generated by a dedicated photovoltaic plant. The next solar assisted option does the same but with an absorption chiller. The steam for this chiller is generated in a solar field equipped with Linear Fresnel Reflectors. The efficiency and the total additional costs for development of these two configurations are estimated with relevant software packages. Similar power augmentation can be achieved with traditional Integrated Solar Combined Cycle plant. All main additional costs for construction of this alternative plant are also estimated. As a result, the specific costs for solar augmentation of a basic GTCC plant are obtained and compared. The configuration with an absorption chiller has lower specific incremental plant capital costs and requires smaller land area than the others. The proposed solar assisted plant concept offers an effective way for further implementation of compact linear Fresnel reflector technology.