Abstract
Fuel cell based systems can be used effectively to supply electricity to an isolated power system. With variations in electricity demand, fuel cell as well as the reformer operates in part load condition and a buffer storage tank is provided to cater to this fluctuating. Efficiency of a reformer deteriorates with part load operations. On the other hand, efficiency of a fuel cell improves during part load operations. It is important to size the buffer tank properly to improve overall system performance. The primary objective of this work is to optimize reformer size and storage volume for a given load profile. In this paper, a methodology, based on the principles of Pinch Analysis, is proposed by dividing the entire load cycle into several time intervals. The net energy balance in every interval is calculated and various design constraints, such as the turndown ratio of the reformer, electricity demand, and no wastage of hydrogen, are imposed. Set of all feasible configurations of the overall system, known as the design space, is identified on a graphical representation between reformer size and storage volume. In addition a sensitivity analysis is also carried to understand the variation of design space with variations in turn down ratio.
