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Pivovar, Bryan S

Publications and source records attributed to Pivovar, Bryan S.

H2@Scale: Economic Potential of Hydrogen as an Energy Intermediate

The H2@Scale concept envisions hydrogen as an energy intermediate across multiple energy sectors. The concept is motivated both by the opportunity to produce hydrogen from low-cost energy resources, and by the many potential applications of hydrogen, including as energy for transportation - used directly in fuel cell electric vehicles (FCEVs), as a feedstock for synthetic fuels, and to upgrade oil and biomass - feedstock for industry (e.g., for ammonia production, metals refining, and other end uses), heat for industry and buildings, and electricity storage. A key hydrogen production opportunity is using variable renewable electricity (i.e., electricity generated by wind turbines or solar photovoltaic panels) during hours when generation exceeds the load on the grid as a source of low-cost, dispatch constrained electricity (LDE). In addition to producing low-cost hydrogen, electrolysis can also serve as a form of responsive load on the electric grid, which can enhance grid stability, reduce curtailment, and create a supplementary revenue stream for generators. The future use and adoption of hydrogen across end-use applications depends both the cost of hydrogen production and on each application's threshold price (i.e., the maximum price each application will pay for hydrogen - above that price, the application has an alternative that is more economic). We estimate economic potential of the hydrogen market - the quantity of hydrogen at an equilibrium price at which suppliers are willing to produce and consumers are willing to buy the same quantity of hydrogen - by developing supply and demand curves for hydrogen production and use. The demand curves are based on the threshold price for various quantities of hydrogen in each market, which is affected by projected prices for alternatives that could provide the same service (e.g., fuel for vehicles, feedstock for metals refining). The supply curves include hydrogen produced via natural gas steam methane reforming, high-temperature electrolysis coupled with nuclear power plants, biomass gasification, and low-temperature electrolysis using LDE. We use a range of market and technology-advancement assumptions to estimate the economic potential for five scenarios in the mid 21st century timeframe, and the corresponding impacts on energy use and emissions. We estimate hydrogen's economic potential to be 14-48 MMT/yr in the contiguous United States - corresponding to 1.5-5 times current annual consumption - depending on key assumptions about the future market conditions and the success of hydrogen production research and development (R&D) in our five scenarios. As a result of the estimated economic potential markets, we also approximate that grid-integrated electrolysis can increase the penetration of wind generation in the electricity market by providing a value stream for LDE, and that total U.S. fossil fuel use could decline below a scenario with high renewable penetration on the grid. We find that hydrogen has potential to provide technical and economic synergies when integrated across multiple sectors of the U.S. energy system, but continued R&D, infrastructure, and market development for LDE are required.

08 HYDROGEN↗

Hydrogen's Expanding Role in the Energy System

Realizing the vision of H2@Scale will require research and investment in efficient hydrogen production methods and upgraded infrastructure. Advances in hydrogen production will allow new applications, such as steelmaking, biofuels production, and fuel cell electric vehicles, to thrive. H2@Scale is a U.S. Dept. of Energy (DOE) initiative that brings together stakeholders to advance affordable hydrogen production, transport, storage, and utilization in multiple energy sectors. H2@Scale will improve the resiliency and reliability of the energy supply chain, increase the competitiveness of U.S. manufacturing, create jobs, and reduce emissions, thereby improving environmental sustainability. Hydrogen has a unique ability to transfer energy across time and economic sectors. The electric grid was designed so that the generated load varies with changes in demand. However, wind and solar power technologies can only generate electricity when each resource is available, making it more difficult to balance the grid. Because hydrogen production can be a large-scale controllable load, it can help address that challenge. Hydrogen can serve as a clean feedstock for diverse applications within the transportation, process industries, and energy sectors. This article describes hydrogen production, application, and infrastructure opportunities. The first part of the article discusses hydrogen production and describes current costs and potential cost reductions that could be enabled by research and development (R&D). The second section discusses key applications that take advantage of hydrogen's chemical properties and its potential as an energy carrier. The final section of the article describes the current hydrogen infrastructure and how it must grow to meet the H2@Scale vision.

08 HYDROGEN↗

Hydrogen's Potential Role in Future Energy Systems

Hydrogen is developing as a key energy interface that can benefit the electricity grid, provide energy storage, and be used in a number of key applications that have limited alternatives to today's fossil-energy sources. In 2015, the global hydrogen market was 60 MMT/yr (8 EJ/yr). The Hydrogen Council estimated that it could grow ten-fold to 600 MMT/yr (80 EJ/yr) if industrial, transportation, buildings, and electrical applications grow [1]. Hydrogen is used extensively in oil refining for hydrocracking and hydrodesulfurization. It is also the key intermediate while producing ammonia which is used primarily as a fertilizer. Additional industrial market opportunities include steel production where hydrogen could replace metallurgical coal as a reductant (for example, in the direct iron reduction process) and as a feedstock with carbon dioxide to produce methanol, Fischer-Tropsch liquids, and other organic chemicals. In transportation, hydrogen can be used in applications powered by fuel cells. Currently, material handling equipment is the primary market; however, heavy- and medium-duty trucks and light duty vehicles are other direct options. In addition, a hydrogen carrier such as ammonia is a key transportation opportunity. Because it is a non-carbon form of energy storage, hydrogen can play a key role in heating buildings, either directly or through combined heat and power generation, and in providing seasonal storage for the electricity grid. Research and development (R&D) that reduce costs will likely be necessary for hydrogen to economically participate in steelmaking and organic chemical markets. Likewise, lower-cost fuel cells will likely be needed for hydrogen to compete in many transportation, heat, and power markets. Hydrogen is primarily produced from natural gas or other organic feedstocks (e.g., oil refinery byproducts) today. R&D that can reduce the capital cost of both low-temperature and high-temperature electrolysis is possible. If the capital costs for low temperature electrolysis can be reduced while keeping its ability to respond to varying power input, it could be a flexible load on the grid. As such, it could utilize power that would otherwise be curtailed and thus increase the market opportunity for variable renewable generation such as wind and photovoltaic solar [2]. Because it is at an elevated temperature, high temperature electrolysis has a higher efficiency. In many sites where both heat and electricity are available (e.g., nuclear power plants) it can be the most cost effective option for producing hydrogen and supporting energy generation facilities that are challenged when competing to produce electricity alone. [1] The Hydrogen Council. Hydrogen Scaling Up. November 2017. [2] Ruth M., Jadun P., Elgowainy A. H2@Scale Analysis. U.S. Department of Energy Hydrogen and Fuel Cells Program 2019 Annual Merit Review and Peer Evaluation Meeting. April 30, 2019.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Perspectives on Low-Temperature Electrolysis and Potential for Renewable Hydrogen at Scale

Hydrogen is an important part of any discussion on sustainability and reduction in emissions across major energy sectors. In addition to being a feedstock and process gas for many industrial processes, hydrogen is emerging as a fuel alternative for transportation applications. Renewable sources of hydrogen are therefore required to increase in capacity. Low-temperature electrolysis of water is currently the most mature method for carbon-free hydrogen generation and is reaching relevant scales to impact the energy landscape. However, costs still need to be reduced to be economical with traditional hydrogen sources. Operating cost reductions are enabled by the recent availability of low-cost sources of renewable energy, and the potential exists for a large reduction in capital cost withmaterial and manufacturing optimization. This article focuses on the current status and development needs by component for the low-temperature electrolysis options.

08 HYDROGEN↗

Preface - JES Focus Issue on Advances in Modern Polymer Electrolyte Fuel Cells in Honor of Shimshon Gottesfeld

The advances in polymer electrolyte fuel cell (PEFC) technologies over the past few decades and particularly over the past few years, have been very impressive. The promise of PEFC-based fuel cell electric vehicles (FCEVs) as long range EVs of zero emissions, high conversion efficiency, and fit for use of fuels from renewable sources, was recognized by pioneers of this technology some 40 years ago, facing at the time significant skepticism. The eventual commercial introduction of FCEVs in 2015 was enabled by the impressive accomplishments of scientists, engineers, and policymakers over that period of time. Among those responsible for the fuel cell community's success, few, if any, have had more impact than Dr. Shimshon Gottesfeld. He is a distinguished fuel cell educator, a passionate fuel cell and alternative fuel advocate, and a pioneering fuel cell innovator, responsible for several critical contributions that helped demonstrate the commercial viability of polymer electrolyte fuel cells. His impact on the field is seen through specific technical accomplishments, the scientists he has mentored, the teams he has led in different topical areas, and his activities as organizer and speaker in technical fuel cell meetings. We are honored to dedicate this focus issue of the Journal of The Electrochemical Society, entitled 'Advances in Modern Polymer Electrolyte Fuel Cells in Honor of Shimshon Gottesfeld,' to Dr. Gottesfeld for his accomplishments in the area of PEFC science and technology.

30 DIRECT ENERGY CONVERSION↗

2D and 3D Characterization of PtNi Nanowire Electrode Composition and Structure

Extended surface Pt or Pt-M (M = Ni or Co) catalysts are a viable alternative to supported nanoparticle catalysts for the oxygen reduction reaction (ORR) at the cathode in proton exchange membrane fuel cells (PEMFCs). The activity and durability of these catalysts in membrane electrode assemblies (MEAs) are greatly dependent on the surface and bulk properties of the catalyst material, integration with ionomer, and the three-dimensional structure of the electrode, necessitating extensive characterization of the catalyst in the electrode at multiple scales. In this work, extended surface PtNi nanowire-based electrocatalysts derived by spontaneous galvanic displacement, and post-treated to obtain high specific and mass activities, are characterized by X-ray spectroscopies to assess catalyst composition and to determine the extent of Pt-Ni alloying. Transmission X-ray microscopy (TXM) is used to generate two- and three-dimensional images of catalyst layers with varied compositions within the electrode to show the distribution of nanowires and to study Ni dissolution and redeposition within the electrode. These techniques are complemented by electron microscopy, which is used to confirm leaching of nickel from the nanowires and its redeposition within the electrode. This process is shown to have detrimental effect on the MEA performance, which can be at least in part recovered by soaking electrodes in acid. The combination of these techniques provides unprecedented detail of the evolution of the nanowire-based extended surface catalyst and electrode structure guiding the targeted design of high performance electrodes based on this class of materials.

36 MATERIALS SCIENCE↗

H2@Scale: Technical and Economic Potential of Hydrogen as an Energy Intermediate

The H2@Scale concept is focused on developing hydrogen as an energy carrier and using hydrogen's properties to improve the national energy system. Specifically hydrogen has the abilities to (1) supply a clean energy source for industry and transportation and (2) increase the profitability of variable renewable electricity generators such as wind turbines and solar photovoltaic (PV) farms by providing value for otherwise potentially-curtailed electricity. Thus the concept also has the potential to reduce oil dependency by providing a low-carbon fuel for fuel cell electric vehicles (FCEVs), reduce emissions of carbon dioxide and pollutants such as NOx, and support domestic energy production, manufacturing, and U.S. economic competitiveness. The analysis reported here focuses on the potential market size and value proposition for the H2@Scale concept. It involves three analysis phases: 1. Initial phase estimating the technical potential for hydrogen markets and the resources required to meet them; 2. National-scale analysis of the economic potential for hydrogen and the interactions between willingness to pay by hydrogen users and the cost to produce hydrogen from various sources; and 3. In-depth analysis of spatial and economic issues impacting hydrogen production and utilization and the markets. Preliminary analysis of the technical potential indicates that the technical potential for hydrogen use is approximately 60 million metric tons (MMT) annually for light duty FCEVs, heavy duty vehicles, ammonia production, oil refining, biofuel hydrotreating, metals refining, and injection into the natural gas system. The technical potential of utility-scale PV and wind generation independently are much greater than that necessary to produce 60 MMT / year hydrogen. Uranium, natural gas, and coal reserves are each sufficient to produce 60 MMT / year hydrogen in addition to their current uses for decades to centuries. National estimates of the economic potential of hydrogen production using steam methane reforming of natural gas, high temperature electrolysis coupled with nuclear power plants, and low temperature electrolysis are reported. To generate the estimates, supply curves for those technologies are used. They are compared to demand curves that describe the market size for hydrogen uses and willingness to pay for that hydrogen. Scenarios are developed at prices where supply meets demand and are used to estimate energy use, emissions, and economic impacts.

13 HYDRO ENERGY↗

Potential Size of and Value Proposition for H2@Scale Concept

The H2@Scale concept is focused on developing hydrogen as an energy carrier and using hydrogen's properties to improve the national energy system. Specifically hydrogen has the abilities to (1) supply a clean energy source for industry and transportation and (2) increase the profitability of variable renewable electricity generators such as wind turbines and solar photovoltaic (PV) farms by providing value for otherwise potentially-curtailed electricity. Thus the concept also has the potential to reduce oil dependency by providing a low-carbon fuel for fuel cell electric vehicles (FCEVs), reduce emissions of carbon dioxide and pollutants such as NOx, and support domestic energy production, manufacturing, and U.S. economic competitiveness. The analysis reported here focuses on the potential market size and value proposition for the H2@Scale concept. It involves three analysis phases: 1. Initial phase estimating the technical potential for hydrogen markets and the resources required to meet them; 2. National-scale analysis of the economic potential for hydrogen and the interactions between willingness to pay by hydrogen users and the cost to produce hydrogen from various sources; and 3. In-depth analysis of spatial and economic issues impacting hydrogen production and utilization and the markets. Preliminary analysis of the technical potential indicates that the technical potential for hydrogen use is approximately 60 million metric tons (MMT) annually for light duty FCEVs, heavy duty vehicles, ammonia production, oil refining, biofuel hydrotreating, metals refining, and injection into the natural gas system. The technical potential of utility-scale PV and wind generation independently are much greater than that necessary to produce 60 MMT / year hydrogen. Uranium, natural gas, and coal reserves are each sufficient to produce 60 MMT / year hydrogen in addition to their current uses for decades to centuries. National estimates of the economic potential of hydrogen production using steam methane reforming of natural gas, high temperature electrolysis coupled with nuclear power plants, and low temperature electrolysis are reported. To generate the estimates, supply curves for those technologies are used. They are compared to demand curves that describe the market size for hydrogen uses and willingness to pay for that hydrogen. Scenarios are developed at prices where supply meets demand and are used to estimate energy use, emissions, and economic impacts.

13 HYDRO ENERGY↗

Advanced membrane electrode assemblies for fuel cells

A method of preparing advanced membrane electrode assemblies (MEA) for use in fuel cells. A base polymer is selected for a base membrane. An electrode composition is selected to optimize properties exhibited by the membrane electrode assembly based on the selection of the base polymer. A property-tuning coating layer composition is selected based on compatibility with the base polymer and the electrode composition. A solvent is selected based on the interaction of the solvent with the base polymer and the property-tuning coating layer composition. The MEA is assembled by preparing the base membrane and then applying the property-tuning coating layer to form a composite membrane. Finally, a catalyst is applied to the composite membrane.

25 ENERGY STORAGE↗