|Institution:||Chalmers University of Technology|
|Full text PDF:||http://studentarbeten.chalmers.se/publication/174167-design-of-a-fuel-cell-system-design-of-a-specification-of-requirements-for-a-fuel-cell-system-for-th|
The idea for this thesis was to design a specification of requirements for a fuel cell system for the electric power production in a 77-foot sailing ship named T/S Prolific. The fuel cells are intended to complement the existing diesel generator, which is used to deliver power to the three phase system and to charge the batteries used for the low voltage applications. The initiative to the project was first taken by Hydrogen Sweden, a non-profit association which has the goal of promoting the use of hydrogen in Sweden. In a fuel cell a reaction takes place where hydrogen and oxygen recombine into water and thereby releasing energy. A cell consists of two electrodes, anode and cathode, with a layer of electrolyte between them. Hydrogen is supplied to the anode and oxygen to the cathode. The reaction in the fuel cell generates electrons which form a current that flows from the anode to the cathode via an external circuit. In order to design the specification of requirements, parameters such as consumed power, voltage and current were measured during one month of sailing. The measured data was then studied and analyzed to achieve a value of the power rating for the new system. Calculations for the volume needed to store the fuel were performed based on the desired running time of the fuel cells. A control system, based on power electronics, to integrate the fuel cells and the generator into a hybrid system were thought of. The fuel cell system that has been studied for T/S Prolific is intended to be silent rather than environmentally benign. This system should be capable of delivering the needed energy during night sailing and for some periods during the day and therefore the power rate was chosen to be 2.5 kW. The cells used in this project will use hydrogen as fuel and the storage was designed to hold enough hydrogen for two days at sea. This amount was calculated to be 1.52 kg which is equivalent to a volume of 100 dm3 at a pressure of 200 bar. The placement of the entire fuel cell system is intended to be above deck to minimize the risk of accidents. This thesis is intended to be a foundation for the design and installation of a fuel cell system in T/S Prolific. The results of the analysis are presented in a specification of requirements table to function as a foundation for the decision-makers and suppliers. These specifications are based solely on technical aspects, and the economical part is up to the decision-makers and suppliers to look into.