Renewable Hydrogen Storage and Transport Conference Session 2: High Density Hydrogen Carriers

Monday, March 11 2:10PM-5:40PM PST at Town and Gown of USC, Los Angeles, CA

This session is designed for those seeking a deep understanding of the cutting-edge technologies and methodologies, with in-depth exploration of the intricacies of hydrogen sourcing and conversion. Talks will touch on potential carriers like formic acid, solid hydrogen, ammonia, and ethylamine. Solar production and e-methanol will also be discussed.

Session Chair: Shaama Sharada, USC Viterbi School of Engineering

Learn more about this session's presentations from leaders in the field:

2:10PM-2:40PM: "The Role of Clean Fuels in advancing California's Energy Transition" 

Plenary Speaker: Siari Sosa, Technology Development Manager, Low Carbon Resources Team, Research, Development and Demonstration, SoCalGa

2:40PM-3:00PM: "Catalytic Technology to Enable Formic Acid and Alcohol Hydrogen Carriers"

Invited Speaker: Dr. Travis J. Williams, Professor of Chemistry, University of Southern California

3:00PM-3:20PM: "Economical Hydrogen Storage and Transport: The Role of Homogeneously Catalyzed Methanol Synthesis"

Invited Speaker: Devinder Mahajan, Professor & Graduate Program Director, Stony Brook University

In the overall scheme involving methanol (MeOH) as a liquid carrier, the overall process economics will drive this pathway for adoption as a storage medium. Economical MeOH production plants of capacities in the range of 100 – 500 tons/day, as opposed to the present 2000+ tons/day are needed.  One of the advanced concepts in methanol synthesis was developed in the author’s laboratories. The Ni metal complexed with N-donor ligands in a highly ionic medium consisting of an alkoxide base dissolved in glyme/methanol solvent mixture can achieve methanol synthesis. At low (<150oC) operating temperatures and pressures (1-3 MPa), the equilibrium conversion of carbon monoxide hydrogenation to methanol is nearly complete (>99%) with commercially comparable reaction rates (to 9 g-mol MeOH.L-1.h-1). Hence, the process can be operated in once-through mode, a marked advantage over the commercial Cu/ZnO based systems that achieves low (~20%) gas conversion and requires rather large gas recycle. The implication of low temperature methanol synthesis in hydrogen storage will be discussed. 

3:20PM-3:40PM: "Safety, Simplicity, Efficiency: Storing H2 as a Solid"

Invited Speaker: Jim Petrecky, VP Sales and Business Development, GKN Hydrogen

3:40PM-4:00PM: Coffee Break

4:00PM-4:20PM: "Decarbonization of Consolidated Edison’s District Steam Heating System with E-methanol"

Invited Speaker: Vijay Srinivasan, Senior Engineer & Metallurgist, Consolidated Edison

The presentation introduces Consolidated Edison of New York, Inc., the utility supplying electric, gas, and steam and its efforts to decarbonize New York City’s energy systems. Focus turns to the multiple decarbonizing initiatives being pursued for the district steam heating and cooling system which connects to 1,600 buildings located between 96th Street to Battery, the southern tip of Manhattan. Up next is the proposal to implement a pilot project to use of e-methanol as a high-density hydrogen carrier. Due to the limited availability of green hydrogen to produce e-methanol, the pilot, if approved, will start with widely available biobased ethanol, primarily in the Midwest.

4:20PM-4:40PM: "The History of Techno-economic Analysis of Photoelectrochemical Hydrogen Production"

Invited Speaker: Todd Deutsch, Senior Scientist, National Renewable Energy Laboratory

The concept of photoelectrochemical (PEC) water splitting to generate hydrogen fuel was first demonstrated in the laboratory on TiO2 over 50 years ago by Fujishima and Honda. Despite continued bench-scale advances, there are still no commercial deployments of this technology. 

About 20 years ago, the US Department of Energy (DOE) funded the development of the Hydrogen Analysis (H2A) tool, a publicly available techno-economic analysis (TEA) modeling framework that established conventions for plant capacity and lifetime, output hydrogen purity and pressure, and included discounted cash flow analysis to calculate a levelized cost of hydrogen (LCOH). In 2009, a rigorous, bottom-up study that costed out components for four canonical photoreactor types (e.g., planar vs. particulate photoabsorbers) used the H2A tool and sensitivity analysis to report LCOH. I will summarize assumptions and key insights from these results, for example, a “Type IV” planar system with optical concentration had a much lower LCOH because it was assumed that it would be able to produce hydrogen at the 300 psi target output pressure without relying on mechanical compression. I will also discuss how sensitivity analysis can be useful for identifying key parameters such as conversion efficiency, absorber lifetime, and semiconductor cost that have the greatest influence on LCOH and how these analyses are used by DOE to establish technical performance targets and inform research priorities.

4:40PM-5:00PM: "Ammonia As a Vector for Distributed Delivery of UHP Hydrogen and Clean Combustion Mixtures"

Submitted Abstract:  Colin Wolden, Colorado School of Mines

This talk provides an overview of the advantages and challenges involved in employing ammonia for storage, transport, and utilization of green hydrogen. First, as liquid at modest temperature and pressure, ammonia is the leading hydrogen carrier in terms of both gravimetric (17.7 wt.%) and volumetric (~11 kg/lit) capacity. Second, ammonia is a major commodity chemical with a global production and distribution network that may be leveraged (>200 MMT/yr). The principal challenge for ammonia as a hydrogen carrier is its efficient decomposition and purification. The reaction is endothermic and commercial catalysts require very high temperature (800ºC). We highlight current research in the field directed at developing both novel catalysts with high activity at low temperature as well as novel processing strategies. We will highlight work in our group using a catalytic membrane reformer for onsite/on-demand hydrogen generation. Here reaction and separation processes are integrated in a single, process-intensified unit operation. Finally, a third advantage of ammonia is utilization. A zero carbon fuel, ammonia provides great flexibility in that it may used directly, completed decomposed and purified into UHP hydrogen, or used to create tunable H2/NH3 fuel blends. The latter can serve as drop-in replacements for hydrocarbons, and we highlight their potential for zero carbon power generation.

5:00PM-5:20PM: "We Need Hydrogen Storage Materials to Bring Dedicated Green Hydrogen into Industry"

Submitted Abstract:  Hanna Breunig, Lawrence Berkeley National Laboratory

Numerous reviews and analysis of hydrogen storage systems have advanced our understanding of the portfolio of technologies available for hydrogen storage and their technical maturity. The suitability of such technologies for storing hydrogen at the scales expected for industry have not been well established, largely due to a lack of data on the real-world requirements for hourly and seasonal storage in such applications. Herein, we use new estimates of the necessary storage capacity to smooth renewable hydrogen delivery from wind and solar facilities powering 1 Gigawatt (GW) scale electrolyzers, to size, model and benchmark liquid organic hydrogen carrier (LOHC) storage against incumbent storage technologies. We present a plausible design for a stationary toluene/methylcyclohexane storage system and compare its performance and cost with other storage technologies for an example wind-solar profile in Southwest Texas. We then use machine learning to develop scaling factors for the hydrogenation, storage, and dehydrogenation systems based on hourly operation data simulated for 50,000 plausible locations using the new NREL GreenHeart Model. Results are used to evaluate the impact of renewable generation profiles on the suitability of the LOHC system based on key technical and economic performance metrics, including levelized cost of storage, capital cost, and energy efficiency.

5:20PM-5:40PM: "Enabling Ethylamine As Liquid Organic Hydrogen Carrier for Ambient Hydrogen Storage"

Submitted Abstract:  Zhenmeng Peng, University of South Carolina

Hydrogen is an appealing energy carrier that can potentially replace conventional fossil fuels in the development of a clean, sustainable hydrogen economy, which would resolve environmental problems caused by the combustion of the non-renewable resources while also meeting the rising demand for energy. However, hydrogen storage has remained a major roadblock in the hydrogen economy development. As a matter of fact, the state-of-the-art methods fall short of the 2025 Department of Energy (DOE) onboard hydrogen storage target of 5.5 wt.% under 85 °C and 12 bars. Herein we report an electrochemical ethylamine/acetonitrile redox method for efficient, high-capacity hydrogen storage under completely ambient conditions. The amine/nitrile redox couple is selected due to their moderate chemical polarity and relatively simple hydrogenation and dehydrogenation pathways, which would aid reaction activation and reduce the energy barrier. Electrochemical potential provides the driving force in CH3CH2NH2 dehydrogenation under ambient conditions, rather than high temperature and pressure that are typically required to thermally drive an endothermic process. We demonstrate effective CH3CN hydrogenation to CH3CH2NH2 for hydrogen uptake and CH3CH2NH2 dehydrogenation to CH3CN for hydrogen release at low overpotentials, using commercial Pt black catalyst in an electrochemical cell. The studied CH3CH2NH2/CH3CN system has a theoretical H2 storage capacity of 8.9 wt.%, well surpassing the 5.5 wt.% DOE target. This study offers a new, effective hydrogen storage strategy that can be extended to many other amine/nitrile redox systems and would help advance the hydrogen economy development.