Thermal integration of Proton Exchange Membrane Fuel Cell with recuperative organic rankine cycle

Abstract

The increased usage of fossil fuels in today's world is leading to an energy crisis and is having a catastrophic impact on our surroundings. There is an immediate need for the development of new, clean and renewable sources of energy especially to power the fuel driven vehicles to decrease the level of carbon footprint around the world. Fuel cells continue to produce power by undergoing a chemical process unlike conventional combustion technology to convert hydrogen-rich fuel into electricity as long as a fuel source is provided and need not be periodically recharged like batteries. The individual fuel cells can be coupled or compiled together to form stacks that can be combined into larger systems and can be scaled based on the requirement. Fuel cell systems have numerous applications from combustion engine replacements for electric vehicles and portable systems for recharging batteries of several devices to large-scale, multi-megawatt installations providing electricity directly to the utility grid. They vary greatly in their size and power output produced. In the present study, thermal integration of Polymer Exchange Membrane Fuel Cell (PEMFC) with Recuperative Organic Rankine Cycle (RORC) is analyzed. The PEMFC has a higher efficiency when compared to conventional energy conversion devices ranging between 40 and 60% and can also be maximized by using regeneration techniques. High temperature PEMFCs also release heat at a useful temperature of 423 K which can further be utilized to extract useful work to improve the overall efficiency of the fuel cell. A further study and analysis of the various processes of thermal regeneration techniques to improve the efficiency of a fuel cell is carried out.