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This presentation from the U.S. Department of Energy's National Renewable Energy Laboratory includes American Recovery and Reinvestment Act (ARRA) fuel cell material handling equipment composite data products for data through the fourth quarter of 2012.
This presentation from the U.S. Department of Energy's National Renewable Energy Laboratory includes composite data products (CDPs) produced in 2013 for state-of-the-art fuel cell voltage durability status.
This presentation from the U.S. Department of Energy's National Renewable Energy Laboratory includes 21 composite data products (CDPs) produced in Spring 2013 for fuel cell backup power systems.
One of the greatest technological hurdles to deployment of fuel cells relates to the sluggish activity, low durability and the high cost of the catalysts that are currently employed. For automotive PEM fuel cells to become commercially viable, the Pt-specific power density would need to be reduced to less than 0.2gPt/kW (at cell voltages >0.65 V). This would require the Pt loadings to be less than 0.15 mg Pt /cm 2 MEA within the membrane electrode assembly. This could be achieved by enhancing the catalytic activity at the cathode, thus lowering its overpotential. Various different Pt-alloys have shown 2-4 times enhanced activities over Pt alone but still suffer some of the same durability issues as that of the pure Pt. There is a general loss of active Pt due to dissolution and sintering. While there have been a number of elegant fundamental experimental and theoretical studies on ideal single crystal Pt and Pt alloy surfaces which have helped to elucidate the factors that control the activity, there have been very few fundamental studies focused on the stability, reactivity and durability of well-defined Pt nanoparticles. We carried out ab initio density functional theory together with a novel double reference method that we developed to simulate constant potential electrochemical systems in order to model the electrocatalytic reduction of oxygen over model Pt alloy surfaces and nanoparticles. These simulations were used to probe the factors that control the electrocatalytic activity, guide the potential selection of new materials and test their stability under reaction conditions. Ab initio calculations were used to determine the reaction energies and activation barriers for a comprehensive array of different elementary adsorption, desorption, surface reaction and diffusion steps over Pt and Pt alloys involved in the electroreduction of oxygen as a function of surface coverage, the electrochemical potential and temperature. The calculations were used to simulate the potential dependent adsorption and surface reaction energies along with activation barriers in order to determine the kinetics for different surface structures and structural features (step edge and corner sites) to provide the necessary input for kinetic Monte Carlo simulations to follow the rates of reaction. More coarse-grained simulated annealing methods were used to help establish the lowest energy structures and morphologies for different Pt and Pt-alloy nanoparticles that form. The results from the DFT calculations were used to establish an ab initio-derived kinetic database that was used in both 2D and 3D kinetic Monte Carlo simulations that were used to follow the electrocatalytic performance over different particle sizes, shapes and compositions. The ab initio calculations together with the kinetic Monte Carlo simulations were used to complete the following objectives: 1) Determine the controlling elementary reaction pathways and intrinsic kinetics involved in ORR and their potential dependent behavior; 2) Establish the influence of the extrinsic reaction environment including surface structure, alloy composition and spatial arrangement and the humidity on ORR kinetics; 3) Elucidate the effects of particle size and morphology as well as the atomic structure and composition of nanoparticles of Pt, Pt 3 Co, Pt 3 Ni, Pt 3 Fe and other Pt-alloys on the electrocatalytic activity and reaction selectivity; 5) Construct surface Pourbaix phase diagrams for different Pt and Pt-alloys in order to map out the most stable surface phases for different material compositions and reaction conditions; 6) Elucidate the mechanisms that control dissolution and re-deposition of Pt.
The goal of this study was to develop a Residential Integrated Ventilation Controller (RIVEC) to reduce the energy impact of required mechanical ventilation by 20%, maintain or improve indoor air quality and provide demand response benefits. This represents potential energy savings of about 140 GWh of electricity and 83 million therms of natural gas as well as proportional peak savings in California. The RIVEC controller is intended to meet the 2008 Title 24 requirements for residential ventilation as well as taking into account the issues of outdoor conditions, other ventilation devices (including economizers), peak demand concerns and occupant preferences. The controller is designed to manage all the residential ventilation systems that are currently available. A key innovation in this controller is the ability to implement the concept of efficacy and intermittent ventilation which allows time shifting of ventilation. Using this approach ventilation can be shifted away from times of high cost or high outdoor pollution towards times when it is cheaper and more effective. Simulations, based on the ones used to develop the new residential ventilation requirements for the California Buildings Energy code, were used to further define the specific criteria and strategies needed for the controller. These simulations provide estimates of the energy, peak power and contaminant improvement possible for different California climates for the various ventilation systems. Results from a field test of the prototype controller corroborate the predicted performance.
This presentation from the U.S. Department of Energy's National Renewable Energy Laboratory includes stationary fuel cell system composite data products for data through the fourth quarter of 2012.
SunLine Transit Agency, which provides public transit services to the Coachella Valley area of California, has demonstrated hydrogen and fuel cell bus technologies for more than 10 years. In May 2010, SunLine began demonstrating the advanced technology (AT) fuel cell bus with a hybrid electric propulsion system, fuel cell power system, and lithium-based hybrid batteries. This report describes operations at SunLine for the AT fuel cell bus and five compressed natural gas buses. The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) is working with SunLine to evaluate the bus in real-world service to document the results and help determine the progress toward technology readiness. NREL has previously published three reports documenting the operation of the fuel cell bus in service. This report provides a summary of the results with a focus on the bus operation from February 2012 through November 2012.
The main objective of this project is to systematically characterize the surface composition, morphology, and electro-catalytic properties of catalysts coated on LSCF, aiming to establish the scientific basis for rational design of high-performance cathodes by combining a porous backbone (such as LSCF) with a thin catalyst coating. The understanding gained will help us to optimize the composition and morphology of the catalyst layer and microstructure of the LSCF backbone for better performance.
This fact sheet describes National Renewable Energy Laboratory's (NREL's) Fuel Cell Technology Status Analysis Project. NREL is seeking fuel cell industry partners from the United States and abroad to participate in an objective and credible analysis of commercially available fuel cell products to benchmark the current state of the technology and support industry growth. Participating fuel cell developers share price information about their fuel cell products and/or raw fuel cell test data related to operations, maintenance, and safety with NREL via the Hydrogen Secure Data Center (HSDC). The limited-access, off-network HSDC houses the data and analysis tools to protect proprietary information. NREL shares individualized data analysis results as detailed data products (DDPs) with the partners who supplied the data. Aggregated results are published as composite data products (CDPs), which show the technology status without identifying individual companies. The CDPs are a primary benchmarking tool for the U.S. Department of Energy and other stakeholders interested in tracking the status of fuel cell technologies. They highlight durability advancements, identify areas for continued development, and help set realistic price expectations at small-volume production.
The proposed research attempted to identify novel biochemical catalysts, catalyst support materials, high-efficiency electron transfer agents between catalyst active sites and electrodes, and solid-phase electrolytes in order to maximize the current density of biochemical fuel cells that utilize various alcohols as substrates.
Our work is focused on membraneless laminar flow fuel cells, an unconventional fuel cell technology, intended to create a system that not only avoids most typical fuel cell drawbacks, but also achieves the highest power density yet recorded for a non-H 2 fuel cell. We have employed rigorous electrochemistry to characterize the high-energy- density fuel BH 4 - , providing important mechanistic insight for anode catalyst choice and avoiding deleterious side reactions. Numerous fuel cell oxidants, used in place of O 2 , are compared in a detailed, uniform manner, and a powerful new oxidant, cerium ammonium nitrate (CAN), is described. The high-voltage BH 4 - /CAN fuel/oxidant combination is employed in a membraneless, room temperature, laminar-flow fuel cell, with herringbone micromixers which provide chaotic-convective flow which, in turn, enhances both the power output and efficiency of the device. We have also been involved in the design of a scaled-up version of the membraneless laminar flow fuel cell intended to provide a 10W output.
Abstract not provided.
Electrolysis of water, particularly in conjunction with renewable energy sources, is potentially a cost-effective and environmentally friendly method of producing hydrogen at dispersed forecourt sites, such as automotive fueling stations. However, state-of-the-art proton-exchange-membrane (PEM) electrolyzer systems have not been economically competitive for forecourt hydrogen production due to their high capital and operating costs, particularly the cost of the electricity used by the electrolyzer stack. The forecourt hydrogen application requires an electrolyzer that produces 1500 kg/day (62.5 kg/hr) hydrogen. At the present time, the markets for PEM electrolyzers are for much smaller units, typically less than 5 kg/hr. Although larger stacks have been developed they have not been commercialized. Thus, PEM electrolyzer systems are generally quite small. The primary feedstock for an electrolyzer is electricity, which could be produced by renewable sources such as wind or solar that do not produce carbon dioxide or other greenhouse gas emissions. In this project, Giner, Inc. (Giner) developed a low-cost, high-efficiency PEM electrolysis stack and system for hydrogen production at moderate pressures of 300 to 400 psig (2170 to 2860 kPa). The electrolyzer stack operates at differential pressure, with hydrogen produced at moderate pressure while oxygen is evolved at near-atmospheric pressure, reducing the cost of the water feed and oxygen handling subsystems. The project included research on catalysts and membranes to improve the efficiency of the electrolysis reaction, as well as development of advanced materials and component fabrication methods to reduce the capital cost of the electrolyzer stack and system. The project culminated in the delivery of a prototype electrolyzer module to the National Renewable Energy Laboratory for testing at the National Wind Technology Center. Electrolyzer stack efficiency of 74% LHV (87%HHV), meeting DOE 2012 targets, was demonstrated using an advanced high-strength membrane. Giner significantly reduced the capital cost of a PEM electrolyzer stack through development of low-cost components and fabrication methods, including a 60% reduction in stack cost. The estimated cost of the present stack design in large-scale production is less than $\$$350/kW. In addition, Giner demonstrated improved lifetimes of the advanced membrane and cell components that can exceed 60,000 hours of operation. An Economic analysis indicates that hydrogen, prior to delivery costs, could be produced for $\$$3.64 per gge (gasoline-gallon equivalent) at an electricity cost of $\$$0.04/kWh utilizing the lower-cost PEM electrolyzer developed in this project assuming high-volume production of large-scale systems.
This report presents a summary of the work performed by LG Fuel Cell Systems Inc. during the project LG Solid Oxide Fuel Cell (SOFC) Model Development (DOE Award Number: DE-FE0000773) which commenced on October 1, 2009 and was completed on March 31, 2013. The aim of this project is for LG Fuel Cell Systems Inc. (formerly known as Rolls-Royce Fuel Cell Systems (US) Inc.) (LGFCS) to develop a multi-physics solid oxide fuel cell (SOFC) computer code (MPC) for performance calculations of the LGFCS fuel cell structure to support fuel cell product design and development. A summary of the initial stages of the project is provided which describes the MPC requirements that were developed and the selection of a candidate code, STAR-CCM+ (CD-adapco). This is followed by a detailed description of the subsequent work program including code enhancement and model verification and validation activities. Details of the code enhancements that were implemented to facilitate MPC SOFC simulations are provided along with a description of the models that were built using the MPC and validated against experimental data. The modeling work described in this report represents a level of calculation detail that has not been previously available within LGFCS.
Fabrication of membrane electrode assemblies (MEAs) depends on creating inks or pastes of catalyst and binder, and applying this suspension to either the membrane (catalyst coated membrane) or gas diffusion media (gas diffusion electrode) and respectively laminating either gas diffusion media or gas diffusion electrodes (GDEs) to the membrane. One barrier to cost effective fabrication for either of these approaches is the development of stable and consistent suspensions. This program investigated the fundamental forces that destabilize the suspensions and developed innovative approaches to create new, highly stable formulations.
The subject report summarizes the results of solid oxide fuel cell development conducted by UTC Power in conjunction with Delphi Automotive Systems under a cost-share program with from October 2008 through March of 2013. Over that period Delphi Automotive Systems developed a nearly four times larger area solid oxide fuel cell stack capable of operating on pre-reformed natural gas and simulated coal gas with durability demonstrated to 5,000 hours and projected to exceed 10,000 hours. The new stack design was scaled to 40-cell stacks with power output in excess of 6.25kW. Delphi also made significant strides in improving the manufacturability, yield and production cost of these solid oxide fuel cells over the course of the program. Concurrently, UTC Power developed a conceptual design for a 120 MW Integrated Gasification Fuel Cell (IGFC) operating on coal syngas with as high as 57% Higher Heating Value (HHV) efficiency as a measure of the feasibility of the technology. Subsequently a 400 kW on-site system preliminary design with 55% Lower Heating Value (LHV) efficiency operating on natural gas was down-selected from eighteen candidate designs. That design was used as the basis for a 25kW breadboard power plant incorporating four Delphi cell stacks that was tested on natural gas before the program was discontinued due to the sale of UTC Power in early 2013. Though the program was cut short of the endurance target of 3,000 hours, many aspects of the technology were proven including: large-area, repeatable cell manufacture, cell stack operation on simulated coal gas and natural gas and integrated power plant operation on natural gas. The potential of the technology for high efficiency stationary electric power generation is clear. Acceptable production costs, durability, and reliability in real world environments are the remaining challenges to commercialization.
Battelle's Economic Analysis of PEM Fuel Cell Systems project was initiated in 2003 to evaluate the technology and markets that are near-term and potentially could support the transition to fuel cells in automotive markets. The objective of Battelle's project was to assist the DOE in developing fuel cell systems for pre-automotive applications by analyzing the technical, economic, and market drivers of direct hydrogen PEM fuel cell adoption. The project was executed over a 6-year period (2003 to 2010) and a variety of analyses were completed in that period. The analyses presented in the final report include: Commercialization scenarios for stationary generation through 2015 (2004); Stakeholder feedback on technology status and performance status of fuel cell systems (2004); Development of manufacturing costs of stationary PEM fuel cell systems for backup power markets (2004); Identification of near-term and mid-term markets for PEM fuel cells (2006); Development of the value proposition and market opportunity of PEM fuel cells in near-term markets by assessing the lifecycle cost of PEM fuel cells as compared to conventional alternatives used in the marketplace and modeling market penetration (2006); Development of the value proposition of PEM fuel cells in government markets (2007); Development of the value proposition and opportunity for large fuel cell system application at data centers and wastewater treatment plants (2008); Update of the manufacturing costs of PEM fuel cells for backup power applications (2009).
Thermoelectric Power Generation (TEPG) is the most efficient and commercially deployable power generation technology for harvesting wasted heat from such things as automobile exhausts, industrial furnaces, and incinerators, and converting it into usable electrical power. We investigated the materials magnesium silicide (Mg2Si) and manganese silicide (MnSi) for TEG. MgSi2 and MnSi are environmentally friendly, have constituent elements that are abundant in the earth's crust, non-toxic, lighter and cheaper. In Phase I, we successfully produced Mg2Si and MnSi material with good TE properties. We developed a novel technique to synthesize Mg2Si with good crystalline quality, which is normally very difficult due to high Mg vapor pressure and its corrosive nature. We produced n-type Mg2Si and p-type MnSi nanocomposite pellets using FAST. Measurements of resistivity and voltage under a temperature gradient indicated a Seebeck coefficient of roughly 120 V/K on average per leg, which is quite respectable. Results indicated however, that issues related to bonding resulted in high resistivity contacts. Determining a bonding process and bonding material that can provide ohmic contact from room temperature to the operating temperature is an essential part of successful device fabrication. Work continues in the development of a process for reproducibly obtaining low resistance electrical contacts.