6. Configurations of Solar Gas Turbines

Components of a gas turbine can be assembled together in many ways, thereby yielding a wide variety of system configurations. It is possible to use multiple units of each type of component (such as compressor, combustor, turbine and shaft). The configuration of a gas turbine, which is also influenced by the intended application, affects the optimal performance of the system. This flexibility in gas turbine configuration provides a good opportunity for the development of the solar gas turbine (SGT) technology. Major configurations of SGTs can be generally classified into solar-only or hybrid categories. Recovery of heat from the exhaust helps to augment the efficiency of the power plant. In this vein, a review of the literature shows that both recuperative and regenerative types of heat exchangers were used on the exit side of the turbine in previous work. Based on the theory of heat exchangers, it is shown in this chapter that recuperative exchangers are most suitable for heat recovery downstream of the turbine. Hybridization and inclusion of a thermal storage unit enhance the performance of SGTs.