Fuel Cells in Aeronautics: Analysis of Solid Oxide Fuel Cell Systems for More-Electric Aircrafts

Aviation emissions are growing faster than any other sector and they risk undermining the progress achieved through emission cuts in other areas of the economy. Rapidly emerging hydrogen- and fuel-cell-based technologies could be developed for future replacement of onboard electrical systems in more-electric or all-electric aircraft. The primary advantages of deploying these technologies are low emissions and low noise (important features for commuter airplanes that take off and land in urban areas). Solid oxide fuel-cell systems could be advantageous for some aeronautical applications due to their capability of accepting hydrocarbons and high energy-density fuels. Moreover, they are suitable for operating in combined heat and power configurations; they recover heat from hightemperature exhaust gases, which could be used to supply thermal loads and thereby reduce the electric power requested by the aircraft. Environmentally Friendly Inter City Aircraft Powered by Fuel Cells is a Sixth Framework Programme project selected by the Aeronautics and Space division of the European Commission and led by the Politecnico di Torino in Turin, Italy.One of the objectives of the project is to carry out a feasibility study on different typologies of more-electric intercity aircraft. After the characterization of the power consumption of electrical and nonelectrical loads, and the definition of mission profiles for three different typologies of passenger aircraft, the design of the solid oxide fuel-cell-based energy system as well as the simulation of complete missions is performed by hypothesizing different system configurations. The simulations concern both the stack (current and current density, cell and stack voltage, etc.) and the balance of plant (air compressor power, gross stack power, system efficiency, etc.). Obtained results are analyzed and discussed.