Ships: Fuel Cells ppsx

Ships: Fuel Cells W Winkler, Hamburg University of Applied Sciences, Hamburg, Germany & 2009 Elsevier B.V. All rights reserved. Introduction in Applications and Technologies The recent fuel cell (FC) development worldwide has always been accompanied by a number of studies and projects investigating the applications of FCs onboard ships. Almost all possible FC types and different fuels such as hydrogen, natural gas (liquefied or pressurized), liquefied pressurized gas (LPG), methanol, and maritime diesel have been considered. These applications of FCs are still mainly focused on onboard power generation (OPU) and propulsion. The types of ships being con- sidered vary from sailing and other leisure boats to fer- ries, naval surface ships, submarines, and special underwater vehicles such as those used for research or military applications. Although civil utilization of FCs is gaining increasing importance, the naval developments are the clear technology drivers. The main FC types of interest are proton-exchange membrane fuel cells (PEMFC), molten carbonate fuel cells (MCFC), and solid oxide fuel cells (SOFC). Table 1 gives an overview of the main outlines of FC types, fuels, and applications that have already been considered. Leisure boats have been the first application of PEMFC with hydrogen as a fuel. Sailing boats have al- ready been equipped with OPU and motorboats have been operated with an electric motor driven by a hydrogen-supplied PEMFC. The low power density of storing hydrogen restricts the hydrogen-fed PEMFC to applications onboard vessels that operate close to filling stations, for example, at a harbor. This was the main reason to study and develop hydrogen-supplied harbor ferries that are required to cover only a short range. The power supply onboard yacht is an interesting entrance market for FCs because the owners are very much interested in a silent low-emission power gener- ator. Owing to the size of yachts, MCFC and SOFC are possible candidates. Possible fuels are LPG or diesel depending on the future FC development. Similar con- siderations can be made for cruise ships. Specifically, those ships that visit sensitive environments such as Arctic areas are ideal future FC users. The different types of cargo ships have no specific characteristics that might allow FCs to find a specific entrance market; however, onboard power generation might be a possible first application. Naval ships need silent and difficult-to-detect power generators, and a distributed power system onboard for propulsion as applicable with FCs may lead to a better survivability. Preferred fuels are logistic fuels such as diesel or kerosene. Depending on the mission, LPG might be acceptable. The hydrogen-supplied PEMFC- based propulsion system of submarines is the only commercially available FC system worldwide. The combination of hydrogen storage in metal hydrides with hydrogen-powered PEMFC allows a signature with al- most no waste heat, avoiding an easy detection. The maritime research needs unmanned underwater vehicles (UUV) with an air-independent propulsion (AIP) system; hydrogen-supplied PEMFC has been chosen in some applications. Naval systems with diesel- supplied SOFC are under development. In both cases, pure oxygen is used for fuel oxidation. The motivation for using FCs onboard ships has been also accompanied by the development of electric ships. For example, the pod drive as a propulsion system has already been commercialized. The FCs are thus a technology that matches very well the general trend of ship architecture development because they directly supply a large amount of electrical power. The flexibility of electric-driven pod systems is an interesting motiv- ation for merchant ships as well; however, military ap- plications were promoting electrical applications strongly. Figure 1 shows the development from inte- grated power systems onboard ships to all electric ship concepts. Integrated power systems already have an electric drive and a reduced number of prime movers resulting in fuel savings and reduced maintenance. The all electric ship concept increases automation and re- duces manning; the elimination of separated auxiliary systems reduces maintenance and saves energy by better system integration. Table 1 Maritime fuel cells (FCs): types, first applications, and fuels Applications PEMFC MCFC SOFC Sailing boat PG: H 2 a Motor boat PR: H 2 a Ferry PR: H 2 ,NG Yacht PG: LP, MD PG: LP, MD Cruise ship PG: LP, MD PG: LP, MD Cargo ships PG: LP, MD PG: LP, MD Naval ship PG, PR: MD PG, PR: MD Submarine PR: H 2 b Underwater vehicle PR: H 2 a PR: MD a a Operating. b Commercial. Note: Hydrogen, H 2 ; natural gas, NG; LPG, LP; methanol, ME; maritime diesel, MD; propulsion, PR; power generation, PG. 338 . proton-exchange membrane fuel cells (PEMFC), molten carbonate fuel cells (MCFC), and solid oxide fuel cells (SOFC). Table 1 gives an overview of the main outlines of FC types, fuels, and applications that. Ships: Fuel Cells W Winkler, Hamburg University of Applied Sciences, Hamburg, Germany & 2009 Elsevier B.V. All rights reserved. Introduction in Applications and Technologies The recent fuel. maintenance and saves energy by better system integration. Table 1 Maritime fuel cells (FCs): types, first applications, and fuels Applications PEMFC MCFC SOFC Sailing boat PG: H 2 a Motor boat PR: