Developments in Ultra-High Efficiency Fuel Cell/Turbine Hybrid Systems and Supporting Technologies

Abstract

FuelCell Energy (FCE) is developing high temperature fuel cell/turbine-based hybrid systems. The development includes both commercial Direct FuelCell/Turbine (DFC/T®) systems as well as Solid Oxide Fuel Cell/Turbine (SOFC/T) systems. It consists of system concepts, design/engineering/demonstration of an alpha-unit sub-megawatt hybrid system, design/engineering of a commercial MW-scale hybrid system, and development of associated supporting technologies. Initial development originated under a Department of Energy (DOE) Vision 21 Program. Follow-on programs have supported further advancement of high temperature fuel cell/turbine hybrids through supporting development of advanced control modules and development of advanced high temperature recuperators (HTR’s), under, respectively, DOE SBIR and EERE Advanced Manufacturing Office (AMO) initiatives. Activities under the former included development of a novel paradigm for advanced control of power plant processes with specific adaptation to hybrid systems and smart grid dispatch. The paradigm involves intelligent control algorithms based on feedforward and feedback dynamic structures. It consists of a combined model-based robust controller and a neural network supervisor (NNS) that together manipulate the power plant actuators to suboptimally control the hybrid system during load ramping maneuvers. Under the latter ongoing effort, FCE is further developing system concepts and components based on microchannel HTR’s. Activities include candidate material screening and environmental testing as well as fabrication and testing of pilot-scale recuperators. The project will culminate in a MW-duty recuperator design that would support FCE’s development efforts toward a commercial MW-scale hybrid system.