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Wang, Xiaohua

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Updated Manufactured Cost Analysis for Proton Exchange Membrane Water Electrolyzers

Enabling rapid and extensive decarbonization within the electric power and industrial sectors is likely to require high levels of renewable energy deployment, supported by technologies that store and transform renewable electricity into other useful forms. Within hard to decarbonize sectors such as organic chemicals and heavy-duty transportation, the use of low-carbon intensity hydrogen as a fuel and chemical building block is emerging as a near-term alternative to reduce their fossil-fuel dependency. Water splitting electrolysis to produce hydrogen requires only water and electricity as inputs, eliminating the use of natural gas in steam methane reforming, which is the conventional hydrogen production pathway. When powered by low-carbon electricity, electrolysis represents an important pathway towards cross-sectoral decarbonization.

08 HYDROGEN↗

Performance and Total Cost of Ownership of a Fuel Cell Hybrid Mining Truck

The main objective of this work was to investigate the potential of hydrogen and fuel cells replacing diesel and internal combustion engines in the ultraclass haul trucks deployed in the mining sector. Performance, range, durability, and cost are the main criteria considered for comparing the two fuels and engine options. Fuel cell system (FCS) performance is characterized in terms of heat rejection, efficiency, and fuel consumption for a hybrid platform equivalent to a 3500 hp diesel engine operating on a representative open pit mining duty cycle. A hybrid platform was chosen because the heat rejection, with a constrained radiator frontal area, limits the maximum fuel cell-rated power by about 50% compared to that of the diesel truck. The hybrid powertrain was 81–88% more efficient than the diesel powertrain on the truck duty cycle. A liquid hydrogen storage system is required for an equal range or time between refilling, but the packaging remains a challenge. Fuel cell and battery durability were evaluated for their performance degradation and lifetime. Achieving a fuel cell lifetime comparable to the time between major overhauls for diesel trucks necessitates the oversizing of the membrane-active area, catalyst overloading, and voltage clipping. For an equal lifetime, the battery must be oversized to control its depth of discharge and charge/discharge rates. A total cost of ownership (TCO) analysis considering the initial capital expenditures, as well as the lifetime cost of fuel, operation, and maintenance, indicates that fuel cells and hydrogen can compete with diesel. A breakeven fuel cost for TCO parity is obtained if H2 is available at USD 5.79–6.85/kg vs. diesel at USD 3.25/gal and the FCS-specific cost is USD 323/kW e relative to USD 250/kW for a diesel genset. Volume manufacturing is required for FCS cost reduction. High volume is possible through the standardization, modularity, and proliferation of class 8 long-haul truck systems across different heavy-duty applications.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Hydrogen for Maritime Applications

The maritime industry is investigating a number of fuel options for reducing emissions, including liquefied natural gas (LNG), biofuels, and electrical drive systems powered by batteries and/or hydrogen-fueled fuel cells. Hydrogen-fueled ships offer the potential to significantly reduce, if not eliminate, regulated and unregulated pollutants in maritime applications. Argonne National Laboratory conducted preliminary comparisons of the total cost of ownership (TCO) of several classes of ships to determine how fuel cell technology compares to the current diesel technology, what advancements are needed for hydrogen fuel cell technology to be competitive in the future, and what applications may be appropriate for introducing fuel cells into the maritime industry. These studies included feeder container ships, harbor tugboats, river pushboats, and auto/passenger ferries. For this study, TCO was defined to include the cost of fuel, propulsion system, and fuel storage system, the levelized cost of propulsion/auxiliary engines, and the cost of annual maintenance and consumables. It did not include the cost of the vessel frame or other components, aside from the propulsion system, that the fuel cell and diesel ships have in common. A 10% internal rate of return (IRR) was applied to the initial capital investment and an installation cost factor of 20% was applied to the capital cost. The capital cost of each component (e.g., engine, fuel tank, motor, etc.) was amortized over a period of 20 years, except for the fuel cell system, which was amortized over 6 or 10 years depending on ship class. The initial comparisons for container ships indicate that fuel costs are by far the dominant contributor to the TCO. With the current low cost of low-sulfur marine gasoil (LSMGO) and relatively high cost of hydrogen, it is difficult for hydrogen to compete with LSMGO in container ship applications. The large energy demand for container ships also favors the use of the higher volumetric energy density LSMGO fuel, especially for longer voyages. The space required to store enough hydrogen for the same journey is larger than that needed to store diesel fuels and can reduce the available cargo carrying and revenue generating space available on the ship.

08 HYDROGEN↗