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Optimization of Zero Emission Hydrogen Fuel Cell Ferry Design With Comparisons to the SF-BREEZE

Pratt, Joseph W.; Klebanoff, Leonard E.

Zero emission hydrogen fuel cell technology has the potential to drastically reduce total "well - to - waves" maritime emissions. Through realistic design studies of five commercially - relevant passenger vessels, this study examines the most cost - effective ent ry points in the US fleet for deploying today' s available technology, and includes analysis of resulting well - to - waves emission profiles. The results show that per - passenger mile vessel energy use is directly correlated to increased emissions, capital cos ts, and operating costs. As a consequence, low speed, large capacity vessels offer a cost - effective starting place today. Increases in vessel efficiency through such measures as hull design and light - weighting can have large impacts in reducing cost and emissions of these systems. Overall this work showed all five vessel types to be feasible with today's hydrogen fuel cell technology and presents more options to fleets that are committed to reducing maritime emissions in cost effective ways.

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Informing hazardous zones for on-board maritime hydrogen liquid and gas systems

Blaylock, Myra L.; Pratt, Joseph W.; Bran Anleu, Gabriela A.; Proctor, Camron P.

The significantly higher buoyancy of hydrogen compared to natural gas means that hazardous zones defined in the IGF code may be inaccurate if applied to hydrogen. This could place undue burden on ship design or could lead to situations that are unknowingly unsafe. We present dispersion analyses to examine three vessel case studies: (1) abnormal external vents of full blowdown of a liquid hydrogen tank due to a failed relief device in still air and with crosswind; (2) vents due to naturally-occurring boil-off of liquid within the tank; and (3) a leak from the pipes leading into the fuel cell room. The size of the hydrogen plumes resulting from a blowdown of the tank depend greatly on the wind conditions. It was also found that for normal operations releasing a small amount of "boil- off" gas to regulate the pressure in the tank does not create flammable concentrations.

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Practical Application Limits of Fuel Cells and Batteries for Zero Emission Vessels

Pratt, Joseph W.; Minnehan, John J.; Pratt, Joseph W.

Batteries and hydrogen fuel cells provide zero emission power at the point of use. They are studied as an alternative powerplant for maritime vessels by considering 14 case studies of various ship sizes and routes varying from small passenger vessels to the largest cargo ships. The method used was to compare the mass and volume of the required zero emission solution to the available mass and volume on an existing vessel considering its current engine and fuel storage systems. The results show that it is practically feasible to consider these zero emission technologies for most vessels in the world's fleet. Hydrogen fuel cells proved to be the most capable while battery systems showed an advantage for high power, short duration missions. The results provide a guide to ship designers to determine the most suitable types of zero emission powerplants to fit a ship based on its size and energy requirements.

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Maritime Fuel Cell Generator Project

Pratt, Joseph W.

Fuel costs and emissions in maritime ports are an opportunity for transportation energy efficiency improvement and emissions reduction efforts. Ocean-going vessels, harbor craft, and cargo handling equipment are still major contributors to air pollution in and around ports. Diesel engine costs continually increase as tighter criteria pollutant regulations come into effect and will continue to do so with expected introduction of carbon emission regulations. Diesel fuel costs will also continue to rise as requirements for cleaner fuels are imposed. Both aspects will increase the cost of diesel-based power generation on the vessel and on shore. Although fuel cells have been used in many successful applications, they have not been technically or commercially validated in the port environment. One opportunity to do so was identified in Honolulu Harbor at the Young Brothers Ltd. wharf. At this facility, barges sail regularly to and from neighbor islands and containerized diesel generators provide power for the reefers while on the dock and on the barge during transport, nearly always at part load. Due to inherent efficiency characteristics of fuel cells and diesel generators, switching to a hydrogen fuel cell power generator was found to have potential emissions and cost savings.

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Comparison of the greenhouse gas and criteria pollutant emissions from the SF-BREEZE high-speed fuel-cell ferry with a diesel ferry

Transportation Research. Part D, Transport and Environment

Klebanoff, Leonard E.; Pratt, Joseph W.

A theoretical comparison is made of the “well to waves” (WTW) greenhouse gas (GHG) and criteria pollutant emissions from the SF-BREEZE high-speed hydrogen PEM fuel cell ferry and the VALLEJO ferry powered by traditional diesel engine technology but constrained to Tier 4 emissions standards. The emissions were calculated for a common maritime mission, the current ferry route between Vallejo CA and San Francisco CA. Calculations are made of the energy required for the SF-BREEZE and VALLEJO to perform the mission route profile. The SF-BREEZE requires 10.1% more fuel energy than the VALLEJO, primarily due to the SF-BREEZE being heavier. Estimates are made for the SF-BREEZE GHG emissions associated with five LH2 fuel production pathways including renewable and non-renewable (fossil-fuel based) methods. Estimates are also made for GHG emissions associated with fossil-diesel production and delivery as well as those for biodiesel, which can be considered a renewable “drop-in” fuel replacement for conventional diesel fuel. We find that the GHG emissions for the SF-BREEZE using non-renewable LH2 are significantly higher than for the Tier 4 diesel-fueled VALLEJO on a per passenger basis. However, using renewable LH2, the GHG emissions for the SF-BREEZE ferry are reduced 75.8% compared to the diesel-fueled VALLEJO operating at Tier 4 emissions standards. We also compare the criteria pollutant emissions (NOx, HC, PM10) for the SF-BREEZE to that of the VALLEJO held to Tier 4 emissions standards fueled by diesel fuel or biodiesel. Hydrogen PEM fuel cell technology dramatically reduces NOx and HC emissions below the most advanced Tier 4 criteria pollutant emissions requirements regardless of whether the LH2 is made by NG reforming or via water electrolysis using 70% renewable energy. Renewable LH2 made with greater than 84% renewable process energy is needed to also drop the SF-BREEZE PM10 emissions below that of Tier 4 for high-speed fuel cell ferry transportation. Overall, the results show that operating a hydrogen fuel cell ferry on nearly 100% renewable hydrogen provides the dramatic reduction in GHG and criteria pollutant emissions commensurate with the problems of global climate change and maritime air pollution worldwide.

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Maritime fuel cell generator project

Pratt, Joseph W.; Chan, Shuk H.

A first-of-its kind hydrogen fuel cell power generator for marine applications was designed, built, and demonstrated to verify increased energy efficiency at part loads and reduced emissions. The project goals were to demonstrate the use of the generator in the maritime environment, identify areas requiring additional research and development, analyze the business case, and address regulatory and other market barriers. A 100 kW generator with 72 kg of hydrogen storage was designed and built by Hydrogenics with safety and regulatory reviews by the Hydrogen Safety Panel, US Coast Guard, and American Bureau of Shipping. Young Brothers operated the generator for 10 months powering refrigerated containers in Honolulu, HI. The project showed it is possible to increase energy efficiency by up to 30% at part load and reduce emissions to zero through the use of hydrogen fuel cells, and identified paths forward to wider adoption of the technology in this sector.

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Comparison of conventional vs. modular hydrogen refueling stations and on-site production vs. delivery

Hecht, Ethan S.; Pratt, Joseph W.

To meet the needs of public and private stakeholders involved in the development, construction, and operation of hydrogen fueling stations needed to support the widespread roll-out of hydrogen fuel cell electric vehicles, this work presents publicly available station templates and analyses. These ‘Reference Stations’ help reduce the cost and speed the deployment of hydrogen stations by providing a common baseline with which to start a design, enable quick assessment of potential sites for a hydrogen station, identify contributors to poor economics, and suggest areas of research. This work presents layouts, bills of materials, piping and instrumentation diagrams, and detailed analyses of five new station designs. In the near term, delivered hydrogen results in a lower cost of hydrogen compared to on-site production via steam methane reforming or electrolysis, although the on-site production methods have other advantages. Modular station concepts including on-site production can reduce lot sizes from conventional assemble-on-site stations.

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Comparison of conventional vs. modular hydrogen refueling stations, and on-site production vs. delivery

Hecht, Ethan S.; Pratt, Joseph W.

To meet the needs of public and private stakeholders involved in the development, construction, and operation of hydrogen fueling stations needed to support the widespread roll-out of hydrogen fuel cell electric vehicles, this work presents publicly available station templates and analyses. These 'Reference Stations' help reduce the cost and speed the deployment of hydrogen stations by providing a common baseline with which to start a design, enable quick assessment of potential sites for a hydrogen station, identify contributors to poor economics, and suggest areas of research. This work presents layouts, bills of materials, piping and instrumentation diagrams, and detailed analyses of five new station designs. In the near term, delivered hydrogen results in a lower cost of hydrogen compared to on-site production via steam methane reforming or electrolysis, although the on-site production methods have other advantages. Modular station concepts including on-site production can reduce lot sizes from conventional assemble-on-site stations.

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Results 1–25 of 60
Results 1–25 of 60