Sizing Hydrogen Energy Storage in Consideration of Demand Response in Highly Renewable Generation Power Systems

Directory of Open Access Journals (Sweden)

Mubbashir Ali

2018-05-01

Full Text Available From an environment perspective, the increased penetration of wind and solar generation in power systems is remarkable. However, as the intermittent renewable generation briskly grows, electrical grids are experiencing significant discrepancies between supply and demand as a result of limited system flexibility. This paper investigates the optimal sizing and control of the hydrogen energy storage system for increased utilization of renewable generation. Using a Finnish case study, a mathematical model is presented to investigate the optimal storage capacity in a renewable power system. In addition, the impact of demand response for domestic storage space heating in terms of the optimal sizing of energy storage is discussed. Finally, sensitivity analyses are conducted to observe the impact of a small share of controllable baseload production as well as the oversizing of renewable generation in terms of required hydrogen storage size.

Safety operation of chromatography column system with discharging hydrogen radiolytically generated

International Nuclear Information System (INIS)

Watanabe, S; Sano, Y.; Nomura, K.; Koma, Y.; Okamoto, Y.

2015-01-01

The extraction chromatography technology is one of the promising methods for the partitioning of minor actinides (Am and Cm) from spent nuclear fuels. In the extraction chromatography system, the accumulation of hydrogen gas in the chromatography column is suspected to lead to fire or explosion. In order to prevent hazardous accidents, it is necessary to evaluate behaviors of gas radiolytically generated inside the column. In this study, behaviors of gas inside the extraction chromatography column were investigated through experiments and Computation Fluid Dynamics (CFD) simulation. N_2 gas once accumulated as bubbles in the packed bed was hardly discharged by the flow of mobile phase. However, the CFD simulation and X-ray imaging on γ-ray irradiated column revealed that during operation the hydrogen gas generated in the column was dissolved into the mobile phase without accumulation and then discharged. (authors)

Final Technical Report for GO15056 Millennium Cell: Development of an Advanced Chemical Hydrogen Storage and Generation System

Energy Technology Data Exchange (ETDEWEB)

Moreno, Oscar [Millennium Cell Inc., Eatontown, NJ (United States)

2017-02-22

The objectives of this project are to increase system storage capacity by improving hydrogen generation from concentrated sodium borohydride, with emphasis on reactor and system engineering; to complete a conceptual system design based on sodium borohydride that will include key technology improvements to enable a hydrogen fuel system that will meet the systembased storage capacity of 1.2 kWh/L (36 g H2/L) and 1.5 kWh/kg (45 g H2/kg), by the end of FY 2007; and to utilize engineering expertise to guide Center research in both off-board chemical hydride regeneration and on-board hydrogen generation systems.

HOGEN{trademark} proton exchange membrane hydrogen generators: Commercialization of PEM electrolyzers

Energy Technology Data Exchange (ETDEWEB)

Smith, W.F.; Molter, T.M. [Proton Energy Systems, Inc., Rocky Hill, CT (United States)

1997-12-31

PROTON Energy Systems` new HOGEN series hydrogen generators are Proton Exchange Membrane (PEM) based water electrolyzers designed to generate 300 to 1000 Standard Cubic Feet Per Hour (SCFH) of high purity hydrogen at pressures up to 400 psi without the use of mechanical compressors. This paper will describe technology evolution leading to the HOGEN, identify system design performance parameters and describe the physical packaging and interfaces of HOGEN systems. PEM electrolyzers have served US and UK Navy and NASA needs for many years in a variety of diverse programs including oxygen generators for life support applications. In the late 1970`s these systems were advocated for bulk hydrogen generation through a series of DOE sponsored program activities. During the military buildup of the 1980`s commercial deployment of PEM hydrogen generators was de-emphasized as priority was given to new Navy and NASA PEM electrolysis systems. PROTON Energy Systems was founded in 1996 with the primary corporate mission of commercializing PEM hydrogen generators. These systems are specifically designed and priced to meet the needs of commercial markets and produced through manufacturing processes tailored to these applications. The HOGEN series generators are the first step along the path to full commercial deployment of PEM electrolyzer products for both industrial and consumer uses. The 300/1000 series are sized to meet the needs of the industrial gases market today and provide a design base that can transition to serve the needs of a decentralized hydrogen infrastructure tomorrow.

A self-regulating hydrogen generator for micro fuel cells

Energy Technology Data Exchange (ETDEWEB)

Moghaddam, Saeed; Pengwang, Eakkachai; Shannon, Mark A. [Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, 1206 West Green Street, Urbana, IL 61801 (United States); Masel, Richard I. [Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 213 Roger Adams Lab, 600 S. Mathews, Urbana, IL 61801 (United States)

2008-10-15

The ever-increasing power demands and miniaturization of portable electronics, micro-sensors and actuators, and emerging technologies such as cognitive arthropods have created a significant interest in development of micro fuel cells. One of the major challenges in development of hydrogen micro fuel cells is the fabrication and integration of auxiliary systems for generating, regulating, and delivering hydrogen gas to the membrane electrode assembly (MEA). In this paper, we report the development of a hydrogen gas generator with a micro-scale control system that does not consume any power. The hydrogen generator consists of a hydride reactor and a water reservoir, with a regulating valve separating them. The regulating valve consists of a port from the water reservoir and a movable membrane with via holes that permit water to flow from the reservoir to the hydride reactor. Water flows towards the hydride reactor, but stops within the membrane via holes due to capillary forces. Water vapor then diffuses from the via holes into the hydride reactor resulting in generation of hydrogen gas. When the rate of hydrogen consumed by the MEA is lower than the generation rate, gas pressure builds up inside the hydride reactor, deflecting the membrane, closing the water regulator valve, until the pressure drops, whereby the valve reopens. We have integrated the self-regulating micro hydrogen generator to a MEA and successfully conducted fuel cell tests under varying load conditions. (author)

The fusion-hydrogen energy system

International Nuclear Information System (INIS)

Williams, L.O.

1994-01-01

This paper will describe the structure of the system, from energy generation and hydrogen production through distribution to the end users. It will show how stationary energy users will convert to hydrogen and will outline ancillary uses of hydrogen to aid in reducing other forms of pollution. It will show that the adoption of the fusion hydrogen energy system will facilitate the use of renewable energy such as wind and solar. The development of highly efficient fuel cells for production of electricity near the user and for transportation will be outlined. The safety of the hydrogen fusion energy system is addressed. This paper will show that the combination of fusion generation combined with hydrogen distribution will provide a system capable of virtually eliminating the negative impact on the environment from the use of energy by humanity. In addition, implementation of the energy system will provide techniques and tools that can ameliorate environmental problems unrelated to energy use. (Author)

Hydrogen generation at ambient conditions: application in fuel cells.

Science.gov (United States)

Boddien, Albert; Loges, Björn; Junge, Henrik; Beller, Matthias

2008-01-01

The efficient generation of hydrogen from formic acid/amine adducts at ambient temperature is demonstrated. The highest catalytic activity (TOF up to 3630 h(-1) after 20 min) was observed in the presence of in situ generated ruthenium phosphine catalysts. Compared to the previously known methods to generate hydrogen from liquid feedstocks, the systems presented here can be operated at room temperature without the need for any high-temperature reforming processes, and the hydrogen produced can then be directly used in fuel cells. A variety of Ru precursors and phosphine ligands were investigated for the decomposition of formic acid/amine adducts. These catalytic systems are particularly interesting for the generation of H2 for new applications in portable electric devices.

Investment in hydrogen tri-generation for wastewater treatment plants under uncertainties

Science.gov (United States)

Gharieh, Kaveh; Jafari, Mohsen A.; Guo, Qizhong

2015-11-01

In this article, we present a compound real option model for investment in hydrogen tri-generation and onsite hydrogen dispensing systems for a wastewater treatment plant under price and market uncertainties. The ultimate objective is to determine optimal timing and investment thresholds to exercise initial and subsequent options such that the total savings are maximized. Initial option includes investment in a 1.4 (MW) Molten Carbonate Fuel Cell (MCFC) fed by mixture of waste biogas from anaerobic digestion and natural gas, along with auxiliary equipment. Produced hydrogen in MCFC via internal reforming, is recovered from the exhaust gas stream using Pressure Swing Adsorption (PSA) purification technology. Therefore the expansion option includes investment in hydrogen compression, storage and dispensing (CSD) systems which creates additional revenue by selling hydrogen onsite in retail price. This work extends current state of investment modeling within the context of hydrogen tri-generation by considering: (i) Modular investment plan for hydrogen tri-generation and dispensing systems, (ii) Multiple sources of uncertainties along with more realistic probability distributions, (iii) Optimal operation of hydrogen tri-generation is considered, which results in realistic saving estimation.

System approach on solar hydrogen generation and the gas utilization; Taiyo energy ni yoru suiso no seisei oyobi sono riyo system ni kansuru kenkyu

Energy Technology Data Exchange (ETDEWEB)

Fujii, I; Hirooka, N; Deguchi, Y; Narita, D [Meiji University, Tokyo (Japan)

1997-11-25

An apparatus is developed to establish a system which allows utilization of hydrogen safely and easily, and its applicability to a hydrogen system for domestic purposes is tested. The system converts solar energy by the photovoltaic cell unit into power, which is used to generate hydrogen by electrolysis of water at the hydrogen generator, stores hydrogen in a metal hydride , and sends stored hydrogen to the burner and fuel cell units. It is found that a hydrogen occluding alloy of LaNi4.8Al0.2 stores hydrogen to approximately 80% when cooled to 20 to 25degC, and releases it to 10% when heated to 40degC. The fuel cell uses a solid polymer as the electrolyte. The hydrogen gas burner is a catalytic combustion burner with a Pt catalyst carried by expanded Ni-Al alloy. The optimum distance between the burner and object to be heated is 22mm. High safety and fabrication simplicity are confirmed for use for domestic purposes. The system characteristics will be further investigated. 4 refs., 8 figs.

Storage, generation, and use of hydrogen

Science.gov (United States)

McClaine, Andrew W.; Rolfe, Jonathan L.; Larsen, Christopher A.; Konduri, Ravi K.

2006-05-30

A composition comprising a carrier liquid; a dispersant; and a chemical hydride. The composition can be used in a hydrogen generator to generate hydrogen for use, e.g., as a fuel. A regenerator recovers elemental metal from byproducts of the hydrogen generation process.

Solar powered hydrogen generating facility and hydrogen powered vehicle fleet. Final technical report, August 11, 1994--January 6, 1997

Energy Technology Data Exchange (ETDEWEB)

Provenzano, J.J.

1997-04-01

This final report describes activities carried out in support of a demonstration of a hydrogen powered vehicle fleet and construction of a solar powered hydrogen generation system. The hydrogen generation system was permitted for construction, constructed, and permitted for operation. It is not connected to the utility grid, either for electrolytic generation of hydrogen or for compression of the gas. Operation results from ideal and cloudy days are presented. The report also describes the achievement of licensing permits for their hydrogen powered trucks in California, safety assessments of the trucks, performance data, and information on emissions measurements which demonstrate performance better than the Ultra-Low Emission Vehicle levels.

Photochemical hydrogen production system

International Nuclear Information System (INIS)

Copeland, R.J.

1990-01-01

Both technical and economic factors affect the cost of producing hydrogen by photochemical processes. Technical factors include the efficiency and the capital and operating costs of the renewable hydrogen conversion system; economic factors include discount rates, economic life, credit for co-product oxygen, and the value of the energy produced. This paper presents technical and economic data for a system that generates on-peak electric power form photochemically produced hydrogen

Water reactive hydrogen fuel cell power system

Science.gov (United States)

Wallace, Andrew P; Melack, John M; Lefenfeld, Michael

2014-01-21

A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into a fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

Comparison of hydrogen production and electrical power generation for energy capture in closed-loop ammonium bicarbonate reverse electrodialysis systems

KAUST Repository

Hatzell, Marta C.; Ivanov, Ivan; D. Cusick, Roland; Zhu, Xiuping; Logan, Bruce E.

2014-01-01

Currently, there is an enormous amount of energy available from salinity gradients, which could be used for clean hydrogen production. Through the use of a favorable oxygen reduction reaction (ORR) cathode, the projected electrical energy generated by a single pass ammonium bicarbonate reverse electrodialysis (RED) system approached 78 W h m-3. However, if RED is operated with the less favorable (higher overpotential) hydrogen evolution electrode and hydrogen gas is harvested, the energy recovered increases by as much ∼1.5× to 118 W h m-3. Indirect hydrogen production through coupling an RED stack with an external electrolysis system was only projected to achieve 35 W h m-3 or ∼1/3 of that produced through direct hydrogen generation.

Comparison of hydrogen production and electrical power generation for energy capture in closed-loop ammonium bicarbonate reverse electrodialysis systems.

Science.gov (United States)

Hatzell, Marta C; Ivanov, Ivan; Cusick, Roland D; Zhu, Xiuping; Logan, Bruce E

2014-01-28

Currently, there is an enormous amount of energy available from salinity gradients, which could be used for clean hydrogen production. Through the use of a favorable oxygen reduction reaction (ORR) cathode, the projected electrical energy generated by a single pass ammonium bicarbonate reverse electrodialysis (RED) system approached 78 W h m(-3). However, if RED is operated with the less favorable (higher overpotential) hydrogen evolution electrode and hydrogen gas is harvested, the energy recovered increases by as much ~1.5× to 118 W h m(-3). Indirect hydrogen production through coupling an RED stack with an external electrolysis system was only projected to achieve 35 W h m(-3) or ~1/3 of that produced through direct hydrogen generation.

Hydrogen generation from natural gas for the fuel cell systems of tomorrow

Science.gov (United States)

Dicks, Andrew L.

In most cases hydrogen is the preferred fuel for use in the present generation of fuel cells being developed for commercial applications. Of all the potential sources of hydrogen, natural gas offers many advantages. It is widely available, clean, and can be converted to hydrogen relatively easily. When catalytic steam reforming is used to generate hydrogen from natural gas, it is essential that sulfur compounds in the natural gas are removed upstream of the reformer and various types of desulfurisation processes are available. In addition, the quality of fuel required for each type of fuel cell varies according to the anode material used, and the cell temperature. Low temperature cells will not tolerate high concentrations of carbon monoxide, whereas the molten fuel cell (MCFC) and solid oxide fuel cell (SOFC) anodes contain nickel on which it is possible to electrochemically oxidise carbon monoxide directly. The ability to internally reform fuel gas is a feature of the MCFC and SOFC. Internal reforming can give benefits in terms of increased electrical efficiency owing to the reduction in the required cell cooling and therefore parasitic system losses. Direct electrocatalysis of hydrocarbon oxidation has been the elusive goal of fuel cell developers over many years and recent laboratory results are encouraging. This paper reviews the principal methods of converting natural gas into hydrogen, namely catalytic steam reforming, autothermic reforming, pyrolysis and partial oxidation; it reviews currently available purification techniques and discusses some recent advances in internal reforming and the direct use of natural gas in fuel cells.

Hydrogen Generation, Combustibility and Mitigation in Nuclear Power Plant Systems

International Nuclear Information System (INIS)

Talha, K.A.; El-Sheikh, B.M.; Gad El-Mawla, A.S.

2003-01-01

The nuclear power plant is provided with features to insure safety. The engineered safety features (ESFs) are devoted to set operating conditions under accident conditions. If ESFs fail to apply in some accidents, this would lead to what called severe accidents, and core damage. In this case hydrogen will be generated from different sources particularly from metal-water reactions. Since the containment is the final barrier to protect the environment from the release of radioactive materials; its integrity should not be threatened. In recent years, hydrogen concentration represents a real problem if it exceeds the combustibility limits. This work is devoted to calculate the amount of hydrogen to be generated, indelicate its combustibility and how to inertize the containment using different gases to maintain its integrity and protect the environment from the release of radioactive materials

Atomistic Modelling of Materials for Clean Energy Applications : hydrogen generation, hydrogen storage, and Li-ion battery

OpenAIRE

Qian, Zhao

2013-01-01

In this thesis, a number of clean-energy materials for hydrogen generation, hydrogen storage, and Li-ion battery energy storage applications have been investigated through state-of-the-art density functional theory. As an alternative fuel, hydrogen has been regarded as one of the promising clean energies with the advantage of abundance (generated through water splitting) and pollution-free emission if used in fuel cell systems. However, some key problems such as finding efficient ways to prod...

WTP Waste Feed Qualification: Hydrogen Generation Rate Measurement Apparatus Testing Report

Energy Technology Data Exchange (ETDEWEB)

Stone, M. E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Newell, J. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Smith, T. E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Pareizs, J. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-06-01

The generation rate of hydrogen gas in the Hanford tank waste will be measured during the qualification of the staged tank waste for processing in the Hanford Tank Waste Treatment and Immobilization Plant. Based on a review of past practices in measurement of the hydrogen generation, an apparatus to perform this measurement has been designed and tested for use during waste feed qualification. The hydrogen generation rate measurement apparatus (HGRMA) described in this document utilized a 100 milliliter sample in a continuously-purged, continuously-stirred vessel, with measurement of hydrogen concentration in the vent gas. The vessel and lid had a combined 220 milliliters of headspace. The vent gas system included a small condenser to prevent excessive evaporative losses from the sample during the test, as well as a demister and filter to prevent particle migration from the sample to the gas chromatography system. The gas chromatograph was an on line automated instrument with a large-volume sample-injection system to allow measurement of very low hydrogen concentrations. This instrument automatically sampled the vent gas from the hydrogen generation rate measurement apparatus every five minutes and performed data regression in real time. The fabrication of the hydrogen generation rate measurement apparatus was in accordance with twenty three (23) design requirements documented in the conceptual design package, as well as seven (7) required developmental activities documented in the task plan associated with this work scope. The HGRMA was initially tested for proof of concept with physical simulants, and a remote demonstration of the system was performed in the Savannah River National Laboratory Shielded Cells Mockup Facility. Final verification testing was performed using non-radioactive simulants of the Hanford tank waste. Three different simulants were tested to bound the expected rheological properties expected during waste feed qualification testing. These

Simultaneous Hydrogen Generation and Waste Acid Neutralization in a Reverse Electrodialysis System

KAUST Repository

Hatzell, Marta C.

2014-09-02

Waste acid streams produced at industrial sites are often co-located with large sources of waste heat (e.g., industrial exhaust gases, cooling water, and heated equipment). Reverse electrodialysis (RED) systems can be used to generate electrical power and hydrogen gas using waste heat-derived solutions, but high electrode overpotentials limit system performance. We show here that an ammonium bicarbonate (AmB) RED system can achieve simultaneous waste acid neutralization and in situ hydrogen production, while capturing energy from excess waste heat. The rate of acid neutralization was dependent on stack flow rate and increased 50× (from 0.06 ± 0.04 to 3.0 ± 0.32 pH units min -1 m-2 membrane), as the flow rate increased 6× (from 100 to 600 mL min-1). Acid neutralization primarily took place due to ammonium electromigration (37 ± 4%) and proton diffusion (60 ± 5%). The use of a synthetic waste acid stream as a catholyte (pH ≈ 2) also increased hydrogen production rates by 65% (from 5.3 ± 0.5 to 8.7 ± 0.1 m3 H2 m-3 catholyte day -1) compared to an AmB electrolyte (pH ≈ 8.5). These findings highlight the potential use of dissimilar electrolytes (e.g., basic anolyte and acidic catholyte) for enhanced power and hydrogen production in RED stacks. © 2014 American Chemical Society.

An appealing photo-powered multi-functional energy system for the poly-generation of hydrogen and electricity

Science.gov (United States)

Tang, Tiantian; Li, Kan; Shen, Zhemin; Sun, Tonghua; Wang, Yalin; Jia, Jinping

2015-10-01

This paper focuses on a photo-powered poly-generation system (PPS) that is powered by the photocatalytic oxidation of organic substrate to produce hydrogen energy and electrical energy synchronously. This particular device runs entirely on light energy and chemical energy of substrate without external voltage. The performance measurements and optimization experiments are all investigated by using the low concentration of pure ethanol (EtOH) solution. Compared with the conventional submerged reactor for the photogeneration of hydrogen, the hydrogen and the electric current obtained in the constructed PPS are all relatively stable in experimental period and the numerical values detected are many times higher than that of the former by using various simulated ethanol waste liquid. When using Chinese rice wine as substrate at the same ethanol content level (i.e., 0.1 mol L-1), the production of hydrogen is close to that of the pure ethanol solution in the constructed PPS, but no hydrogen is detected in the conventional submerged reactor. These results demonstrate that the constructed PPS could effectively utilize light energy and perform good capability in poly-generation of hydrogen and electricity.

Liquid-phase chemical hydrogen storage: catalytic hydrogen generation under ambient conditions.

Science.gov (United States)

Jiang, Hai-Long; Singh, Sanjay Kumar; Yan, Jun-Min; Zhang, Xin-Bo; Xu, Qiang

2010-05-25

There is a demand for a sufficient and sustainable energy supply. Hence, the search for applicable hydrogen storage materials is extremely important owing to the diversified merits of hydrogen energy. Lithium and sodium borohydride, ammonia borane, hydrazine, and formic acid have been extensively investigated as promising hydrogen storage materials based on their relatively high hydrogen content. Significant advances, such as hydrogen generation temperatures and reaction kinetics, have been made in the catalytic hydrolysis of aqueous lithium and sodium borohydride and ammonia borane as well as in the catalytic decomposition of hydrous hydrazine and formic acid. In this Minireview we briefly survey the research progresses in catalytic hydrogen generation from these liquid-phase chemical hydrogen storage materials.

Research on hydrogen production system

International Nuclear Information System (INIS)

Nakagiri, Toshio

2002-07-01

Hydrogen is closely watched for environmental issues in recent years. In this research, hydrogen production systems and production techniques are widely investigated, and selected some hydrogen production process which have high validity for FBR system. Conclusions of the investigation are shown below. (1) Water-electrolysis processes and steam reform processes at low temperatures are already realized in other fields, so they well be easily adopted for FBR system. FBR system has no advantage when compared with other systems, because water-electrolysis processes can be adopted for other electricity generation system. On the other hand, FBR system has an advantage when steam reforming processes at low temperatures will be adopted, because steam reforming processes at 550-600degC can't be adopted for LWR. (2) Thermochemical processes will be able to adopted for FBR when process temperature will be lowered and material problems solved, because their efficiencies are expected high. Radiolysis processes which use ray (for example, gamma rya) emitted in reactor can be generate hydrogen easily, so they will be able to be adopted for FBR if splitting efficiency will be higher. Further investigation and R and D to realize these processes are considered necessary. (author)

Dealloyed Ruthenium Film Catalysts for Hydrogen Generation from Chemical Hydrides

Directory of Open Access Journals (Sweden)

Ramis B. Serin

2017-07-01

Full Text Available Thin-film ruthenium (Ru and copper (Cu binary alloys have been prepared on a Teflon™ backing layer by cosputtering of the precious and nonprecious metals, respectively. Alloys were then selectively dealloyed by sulfuric acid as an etchant, and their hydrogen generation catalysts performances were evaluated. Sputtering time and power of Cu atoms have been varied in order to tailor the hydrogen generation performances. Similarly, dealloying time and the sulfuric acid concentration have also been altered to tune the morphologies of the resulted films. A maximum hydrogen generation rate of 35 mL min−1 was achieved when Cu sputtering power and time were 200 W and 60 min and while acid concentration and dealloying time were 18 M and 90 min, respectively. It has also been demonstrated that the Ru content in the alloy after dealloying gradually increased with the increasing the sputtering power of Cu. After 90 min dealloying, the Ru to Cu ratio increased to about 190 times that of bare alloy. This is the key issue for observing higher catalytic activity. Interestingly, we have also presented template-free nanoforest-like structure formation within the context of one-step alloying and dealloying used in this study. Last but not least, the long-time hydrogen generation performances of the catalysts system have also been evaluated along 3600 min. During the first 600 min, the catalytic activity was quite stable, while about 24% of the catalytic activity decayed after 3000 min, which still makes these systems available for the development of robust catalyst systems in the area of hydrogen generation.

Hydrogen system (hydrogen fuels feasibility)

International Nuclear Information System (INIS)

Guarna, S.

1991-07-01

This feasibility study on the production and use of hydrogen fuels for industry and domestic purposes includes the following aspects: physical and chemical properties of hydrogen; production methods steam reforming of natural gas, hydrolysis of water; liquid and gaseous hydrogen transportation and storage (hydrogen-hydride technology); environmental impacts, safety and economics of hydrogen fuel cells for power generation and hydrogen automotive fuels; relevant international research programs

On-Board Hydrogen Gas Production System For Stirling Engines

Science.gov (United States)

Johansson, Lennart N.

2004-06-29

A hydrogen production system for use in connection with Stirling engines. The production system generates hydrogen working gas and periodically supplies it to the Stirling engine as its working fluid in instances where loss of such working fluid occurs through usage through operation of the associated Stirling engine. The hydrogen gas may be generated by various techniques including electrolysis and stored by various means including the use of a metal hydride absorbing material. By controlling the temperature of the absorbing material, the stored hydrogen gas may be provided to the Stirling engine as needed. A hydrogen production system for use in connection with Stirling engines. The production system generates hydrogen working gas and periodically supplies it to the Stirling engine as its working fluid in instances where loss of such working fluid occurs through usage through operation of the associated Stirling engine. The hydrogen gas may be generated by various techniques including electrolysis and stored by various means including the use of a metal hydride absorbing material. By controlling the temperature of the absorbing material, the stored hydrogen gas may be provided to the Stirling engine as needed.

Start up system for hydrogen generator used with an internal combustion engine

Science.gov (United States)

Houseman, J.; Cerini, D. J. (Inventor)

1977-01-01

A hydrogen generator provides hydrogen rich product gases which are mixed with the fuel being supplied to an internal combustion engine for the purpose of enabling a very lean mixture of that fuel to be used, whereby nitrous oxides emitted by the engine are minimized. The hydrogen generator contains a catalyst which must be heated to a pre-determined temperature before it can react properly. To simplify the process of heating up the catalyst at start-up time, either some of the energy produced by the engine such as engine exhaust gas, or electrical energy produced by the engine, or the engine exhaust gas may be used to heat up air which is then used to heat the catalyst.

Hourly energy management for grid-connected wind-hydrogen systems

International Nuclear Information System (INIS)

Bernal-Agustin, Jose L.; Dufo-Lopez, Rodolfo

2008-01-01

This paper is a complete technical-economic analysis of the hourly energy management of the energy generated in wind-hydrogen systems. Wind power generation depends on the unpredictable nature of the wind. If the wind-power penetration becomes high in the Spanish electrical grid, energy management will be necessary for some wind farms. A method is proposed in this paper to adjust the generation curve to the demand curve, consisting of the generation of hydrogen and storing it in a hydrogen tank during off-peak (low demand) hours, while during the rest of the hours (peak hours, high demand) the stored hydrogen can be used to generate electricity. After revising the results obtained in this paper, for the current values of efficiency of the electricity-hydrogen-electricity conversion (approximately 30%) and due to the high cost of the hydrogen components, for a wind-hydrogen system to be economically viable the price of the sale of the energy generated by the fuel cell would be very high (approximately 171 cEUR/kWh). (author)

Hydrogen generation from biogenic and fossil fuels by autothermal reforming

Science.gov (United States)

Rampe, Thomas; Heinzel, Angelika; Vogel, Bernhard

Hydrogen generation for fuel cell systems by reforming technologies from various fuels is one of the main fields of investigation of the Fraunhofer ISE. Suitable fuels are, on the one hand, gaseous hydrocarbons like methane, propane but also, on the other hand, liquid hydrocarbons like gasoline and alcohols, e.g., ethanol as biogenic fuel. The goal is to develop compact systems for generation of hydrogen from fuel being suitable for small-scale membrane fuel cells. The most recent work is related to reforming according to the autothermal principle — fuel, air and steam is supplied to the reactor. Possible applications of such small-scale autothermal reformers are mobile systems and also miniature fuel cell as co-generation plant for decentralised electricity and heat generation. For small stand-alone systems without a connection to the natural gas grid liquid gas, a mixture of propane and butane is an appropriate fuel.

Hydrogen Generation from Biomass-Derived Surgar Alcohols via the Aqueous-Phase Carbohydrate Reforming (ACR) Process

Energy Technology Data Exchange (ETDEWEB)

Randy Cortright

2006-06-30

This project involved the investigation and development of catalysts and reactor systems that will be cost-effective to generate hydrogen from potential sorbitol streams. The intention was to identify the required catalysts and reactors systems as well as the design, construction, and operation of a 300 grams per hour hydrogen system. Virent was able to accomplish this objective with a system that generates 2.2 kgs an hour of gas containing both hydrogen and alkanes that relied directly on the work performed under this grant. This system, funded in part by the local Madison utility, Madison, Gas & Electric (MGE), is described further in the report. The design and development of this system should provide the necessary scale-up information for the generation of hydrogen from corn-derived sorbitol.

Rapid hydrogen gas generation using reactive thermal decomposition of uranium hydride.

Energy Technology Data Exchange (ETDEWEB)

Kanouff, Michael P.; Van Blarigan, Peter; Robinson, David B.; Shugard, Andrew D.; Gharagozloo, Patricia E.; Buffleben, George M.; James, Scott Carlton; Mills, Bernice E.

2011-09-01

Oxygen gas injection has been studied as one method for rapidly generating hydrogen gas from a uranium hydride storage system. Small scale reactors, 2.9 g UH{sub 3}, were used to study the process experimentally. Complimentary numerical simulations were used to better characterize and understand the strongly coupled chemical and thermal transport processes controlling hydrogen gas liberation. The results indicate that UH{sub 3} and O{sub 2} are sufficiently reactive to enable a well designed system to release gram quantities of hydrogen in {approx} 2 seconds over a broad temperature range. The major system-design challenge appears to be heat management. In addition to the oxidation tests, H/D isotope exchange experiments were performed. The rate limiting step in the overall gas-to-particle exchange process was found to be hydrogen diffusion in the {approx}0.5 {mu}m hydride particles. The experiments generated a set of high quality experimental data; from which effective intra-particle diffusion coefficients can be inferred.

Hydrogen-based power generation from bioethanol steam reforming

Energy Technology Data Exchange (ETDEWEB)

Tasnadi-Asztalos, Zs., E-mail: tazsolt@chem.ubbcluj.ro; Cormos, C. C., E-mail: cormos@chem.ubbcluj.ro; Agachi, P. S. [Babes-Bolyai University, Faculty of Chemistry and Chemical Engineering, 11 Arany Janos, Postal code: 400028, Cluj-Napoca (Romania)

2015-12-23

This paper is evaluating two power generation concepts based on hydrogen produced from bioethanol steam reforming at industrial scale without and with carbon capture. The power generation from bioethanol conversion is based on two important steps: hydrogen production from bioethanol catalytic steam reforming and electricity generation using a hydrogen-fuelled gas turbine. As carbon capture method to be assessed in hydrogen-based power generation from bioethanol steam reforming, the gas-liquid absorption using methyl-di-ethanol-amine (MDEA) was used. Bioethanol is a renewable energy carrier mainly produced from biomass fermentation. Steam reforming of bioethanol (SRE) provides a promising method for hydrogen and power production from renewable resources. SRE is performed at high temperatures (e.g. 800-900°C) to reduce the reforming by-products (e.g. ethane, ethene). The power generation from hydrogen was done with M701G2 gas turbine (334 MW net power output). Hydrogen was obtained through catalytic steam reforming of bioethanol without and with carbon capture. For the evaluated plant concepts the following key performance indicators were assessed: fuel consumption, gross and net power outputs, net electrical efficiency, ancillary consumptions, carbon capture rate, specific CO{sub 2} emission etc. As the results show, the power generation based on bioethanol conversion has high energy efficiency and low carbon footprint.

Hydrogen-based power generation from bioethanol steam reforming

International Nuclear Information System (INIS)

Tasnadi-Asztalos, Zs.; Cormos, C. C.; Agachi, P. S.

2015-01-01

This paper is evaluating two power generation concepts based on hydrogen produced from bioethanol steam reforming at industrial scale without and with carbon capture. The power generation from bioethanol conversion is based on two important steps: hydrogen production from bioethanol catalytic steam reforming and electricity generation using a hydrogen-fuelled gas turbine. As carbon capture method to be assessed in hydrogen-based power generation from bioethanol steam reforming, the gas-liquid absorption using methyl-di-ethanol-amine (MDEA) was used. Bioethanol is a renewable energy carrier mainly produced from biomass fermentation. Steam reforming of bioethanol (SRE) provides a promising method for hydrogen and power production from renewable resources. SRE is performed at high temperatures (e.g. 800-900°C) to reduce the reforming by-products (e.g. ethane, ethene). The power generation from hydrogen was done with M701G2 gas turbine (334 MW net power output). Hydrogen was obtained through catalytic steam reforming of bioethanol without and with carbon capture. For the evaluated plant concepts the following key performance indicators were assessed: fuel consumption, gross and net power outputs, net electrical efficiency, ancillary consumptions, carbon capture rate, specific CO 2 emission etc. As the results show, the power generation based on bioethanol conversion has high energy efficiency and low carbon footprint

Hydrogen-based power generation from bioethanol steam reforming

Science.gov (United States)

Tasnadi-Asztalos, Zs.; Cormos, C. C.; Agachi, P. S.

2015-12-01

This paper is evaluating two power generation concepts based on hydrogen produced from bioethanol steam reforming at industrial scale without and with carbon capture. The power generation from bioethanol conversion is based on two important steps: hydrogen production from bioethanol catalytic steam reforming and electricity generation using a hydrogen-fuelled gas turbine. As carbon capture method to be assessed in hydrogen-based power generation from bioethanol steam reforming, the gas-liquid absorption using methyl-di-ethanol-amine (MDEA) was used. Bioethanol is a renewable energy carrier mainly produced from biomass fermentation. Steam reforming of bioethanol (SRE) provides a promising method for hydrogen and power production from renewable resources. SRE is performed at high temperatures (e.g. 800-900°C) to reduce the reforming by-products (e.g. ethane, ethene). The power generation from hydrogen was done with M701G2 gas turbine (334 MW net power output). Hydrogen was obtained through catalytic steam reforming of bioethanol without and with carbon capture. For the evaluated plant concepts the following key performance indicators were assessed: fuel consumption, gross and net power outputs, net electrical efficiency, ancillary consumptions, carbon capture rate, specific CO2 emission etc. As the results show, the power generation based on bioethanol conversion has high energy efficiency and low carbon footprint.

Hydrogen, a bridge between mobility and distributed generation. Some consideration towards the hydrogen economy

International Nuclear Information System (INIS)

Valentino Romeri

2006-01-01

In this paper were analysed the most recent energy initiatives started by some national and international institution, with particular focus on hydrogen and fuel cell. It were also overviewed the national road-maps towards the hydrogen economy. In 2004, based on the most authoritative available data regarding future FCVs penetration it was observed that, if vehicle power-generation system fuel cell based becomes more sophisticated, the role of the vehicles within the power grid might change. Fuel Cell Vehicle (FVC) could become a new power-generation source, supplying electricity to home and to the grid. Also, it was defined the dimension of this new kind of power generation source in different areas and it was compared with the related power grid installed generation capacity and it was found that this new source could be a multiple of the foreseeable installed capacity in year 2030. In the present work it was revised the analysis with the most recent scenarios and it was found that the results do not change significantly. Unfortunately this kind of analysis is still not considered in the energy debate or in the road-maps towards the hydrogen economy. (author)

Analysis of Hybrid Hydrogen Systems: Final Report

Energy Technology Data Exchange (ETDEWEB)

Dean, J.; Braun, R.; Munoz, D.; Penev, M.; Kinchin, C.

2010-01-01

Report on biomass pathways for hydrogen production and how they can be hybridized to support renewable electricity generation. Two hybrid systems were studied in detail for process feasibility and economic performance. The best-performing system was estimated to produce hydrogen at costs ($1.67/kg) within Department of Energy targets ($2.10/kg) for central biomass-derived hydrogen production while also providing value-added energy services to the electric grid.

IEA Hydrogen Implementing Agreement's Second Generation R and D and the Hydrogen Economy

Energy Technology Data Exchange (ETDEWEB)

Beck, N.; Garcia-Conde, A. G.; Riis, T. U.; Luzzi, A.; Valladares, M. R. de

2005-07-01

Since its creation by the International Energy Agency in the late 1970's, the IEA Hydrogen Implementing Agreement (HIA) has been at the forefront of collaborative international hydrogen research and development (R and D) (http://www.ieahia.org. ) The collective body of HIA hydrogen R and D will contribute to definition of the hydrogen economy. The five-year [2004-2009) mission of the IEA HIA is to advance the adoption of a Hydrogen Economy through strategic implementation of collaborative R and D and outreach programs that address key issues and barriers. The three goals for the Second Generation HIA are: Advancement of science and technology via pre-commercial collaborative RD and D programs; Assessment of market environment, including the non-energy sector; and Implementation of outreach program, aimed at community acceptance and support. The HIA launched its Second Generation of hydrogen R and D in the latter part of 2004. The HIA's anniversary report: In Pursuit of the Future: 25 Years of IEA Research towards the realization of Hydrogen Energy Systems (http://ieahia.org/pdfs/IEA_AnniversaryReport_HIA.pdf) chronicles its contributions to hydrogen R and D. As the hydrogen economy takes shape, the HIA is pleased to share highlights of its R and D history together with progress on planned activities and its six current annexes, listed below: Task 15 Photobiological Production of Hydrogen Task 16 Hydrogen from Carbon-Containing Materials Task 17 Solid and Liquid Storage Task 18 Integrated Systems Evaluation Task 19 Safety Task 20 Hydrogen from Waterphotolysis Planned successor annexes in storage and photobiological hydrogen production will also be discussed, along with a task on high temperature hydrogen production that is now in the definition phase. Over 250 experts from the sixteen member HIA countries and the European Union contribute to this portfolio of cutting edge hydrogen R and D and analysis activities. Several other countries are expected to

Steam generators of Phenix: Measurement of the hydrogen concentration in sodium for detecting water leaks in the steam generator tubes

International Nuclear Information System (INIS)

Cambillard, E.; Lacroix, A.; Langlois, J.; Viala, J.

1975-01-01

The Phenix secondary circuits are provided with measurement systems of hydrogen concentration in sodium, that allow for the detection of possible water leaks in steam generators and the location of a faulty module. A measurement device consists of : a detector with nickel membranes of 0, 3 mm wall thickness, an ion pump with a 200 l/s flow rate, a quadrupole mass spectrometer and a calibrated hydrogen leak. The temperature correction is made automatically. The main tests carried out on the leak detection systems are reported. Since the first system operation (October 24, 1973), the measurements allowed us to obtain the hydrogen diffusion rates through the steam generator tube walls. (author)

Purdue Hydrogen Systems Laboratory

Energy Technology Data Exchange (ETDEWEB)

Jay P Gore; Robert Kramer; Timothee L Pourpoint; P. V. Ramachandran; Arvind Varma; Yuan Zheng

2011-12-28

The Hydrogen Systems Laboratory in a unique partnership between Purdue University's main campus in West Lafayette and the Calumet campus was established and its capabilities were enhanced towards technology demonstrators. The laboratory engaged in basic research in hydrogen production and storage and initiated engineering systems research with performance goals established as per the USDOE Hydrogen, Fuel Cells, and Infrastructure Technologies Program. In the chemical storage and recycling part of the project, we worked towards maximum recycling yield via novel chemical selection and novel recycling pathways. With the basic potential of a large hydrogen yield from AB, we used it as an example chemical but have also discovered its limitations. Further, we discovered alternate storage chemicals that appear to have advantages over AB. We improved the slurry hydrolysis approach by using advanced slurry/solution mixing techniques. We demonstrated vehicle scale aqueous and non-aqueous slurry reactors to address various engineering issues in on-board chemical hydrogen storage systems. We measured the thermal properties of raw and spent AB. Further, we conducted experiments to determine reaction mechanisms and kinetics of hydrothermolysis in hydride-rich solutions and slurries. We also developed a continuous flow reactor and a laboratory scale fuel cell power generation system. The biological hydrogen production work summarized as Task 4.0 below, included investigating optimal hydrogen production cultures for different substrates, reducing the water content in the substrate, and integrating results from vacuum tube solar collector based pre and post processing tests into an enhanced energy system model. An automated testing device was used to finalize optimal hydrogen production conditions using statistical procedures. A 3 L commercial fermentor (New Brunswick, BioFlo 115) was used to finalize testing of larger samples and to consider issues related to scale up

Purdue Hydrogen Systems Laboratory

International Nuclear Information System (INIS)

Gore, Jay P.; Kramer, Robert; Pourpoint, Timothee L.; Ramachandran, P.V.; Varma, Arvind; Zheng, Yuan

2011-01-01

The Hydrogen Systems Laboratory in a unique partnership between Purdue University's main campus in West Lafayette and the Calumet campus was established and its capabilities were enhanced towards technology demonstrators. The laboratory engaged in basic research in hydrogen production and storage and initiated engineering systems research with performance goals established as per the USDOE Hydrogen, Fuel Cells, and Infrastructure Technologies Program. In the chemical storage and recycling part of the project, we worked towards maximum recycling yield via novel chemical selection and novel recycling pathways. With the basic potential of a large hydrogen yield from AB, we used it as an example chemical but have also discovered its limitations. Further, we discovered alternate storage chemicals that appear to have advantages over AB. We improved the slurry hydrolysis approach by using advanced slurry/solution mixing techniques. We demonstrated vehicle scale aqueous and non-aqueous slurry reactors to address various engineering issues in on-board chemical hydrogen storage systems. We measured the thermal properties of raw and spent AB. Further, we conducted experiments to determine reaction mechanisms and kinetics of hydrothermolysis in hydride-rich solutions and slurries. We also developed a continuous flow reactor and a laboratory scale fuel cell power generation system. The biological hydrogen production work summarized as Task 4.0 below, included investigating optimal hydrogen production cultures for different substrates, reducing the water content in the substrate, and integrating results from vacuum tube solar collector based pre and post processing tests into an enhanced energy system model. An automated testing device was used to finalize optimal hydrogen production conditions using statistical procedures. A 3 L commercial fermentor (New Brunswick, BioFlo 115) was used to finalize testing of larger samples and to consider issues related to scale up. Efforts

Nuclear excited power generation system

International Nuclear Information System (INIS)

Parker, R.Z.; Cox, J.D.

1989-01-01

A power generation system is described, comprising: a gaseous core nuclear reactor; means for passing helium through the reactor, the helium being excited and forming alpha particles by high frequency radiation from the core of the gaseous core nuclear reactor; a reaction chamber; means for coupling chlorine and hydrogen to the reaction chamber, the helium and alpha particles energizing the chlorine and hydrogen to form a high temperature, high pressure hydrogen chloride plasma; means for converting the plasma to electromechanical energy; means for coupling the helium back to the gaseous core nuclear reactor; and means for disassociating the hydrogen chloride to form molecular hydrogen and chlorine, to be coupled back to the reaction chamber in a closed loop. The patent also describes a power generation system comprising: a gaseous core nuclear reactor; means for passing hydrogen through the reactor, the hydrogen being excited by high frequency radiation from the core; means for coupling chlorine to a reaction chamber, the hydrogen energizing the chlorine in the chamber to form a high temperature, high pressure hydrogen chloride plasma; means for converting the plasma to electromechanical energy; means for disassociating the hydrogen chloride to form molecular hydrogen and chlorine, and means for coupling the hydrogen back to the gaseous core nuclear reactor in a closed loop

Simultaneous Hydrogen Generation and Waste Acid Neutralization in a Reverse Electrodialysis System

KAUST Repository

Hatzell, Marta C.; Zhu, Xiuping; Logan, Bruce E.

2014-01-01

power and hydrogen gas using waste heat-derived solutions, but high electrode overpotentials limit system performance. We show here that an ammonium bicarbonate (AmB) RED system can achieve simultaneous waste acid neutralization and in situ hydrogen

Performance analysis of an integrated biomass gasification and PEMFC (proton exchange membrane fuel cell) system: Hydrogen and power generation

International Nuclear Information System (INIS)

Chutichai, Bhawasut; Authayanun, Suthida; Assabumrungrat, Suttichai; Arpornwichanop, Amornchai

2013-01-01

The PEMFC (proton exchange membrane fuel cell) is expected to play a significant role in next-generation energy systems. Because most hydrogen that is used as a fuel for PEMFCs is derived from the reforming of natural gas, the use of renewable energy sources such as biomass to produce this hydrogen offers a promising alternative. This study is focused on the performance analysis of an integrated biomass gasification and PEMFC system. The combined heat and power generation output of this integrated system is designed for residential applications, taking into account thermal and electrical demands. A flowsheet model of the integrated PEMFC system is developed and employed to analyze its performance with respect to various key operating parameters. A purification process consisting of a water–gas shift reactor and a preferential oxidation reactor is also necessary in order to reduce the concentration of CO in the synthesis gas to below 10 ppm for subsequent use in the PEMFC. The effect of load level on the performance of the PEMFC system is investigated. Based on an electrical load of 5 kW, it is found that the electrical efficiency of the PEMFC integrated system is 22%, and, when waste heat recovery is considered, the total efficiency of the PEMFC system is 51%. - Highlights: • Performance of a biomass gasification and PEMFC integrated system is analyzed. • A flowsheet model of the PEMFC integrated system is developed. • Effect of biomass sources and key parameters on hydrogen and power generation is presented. • The PEMFC integrated system is designed for small-scale power demand. • Effect of load changes on the performance of PEMFC is investigated

Efficiency Evaluation of a Photovoltaic System Simultaneously Generating Solar Electricity and Hydrogen for Energy Storage

Directory of Open Access Journals (Sweden)

Abermann S.

2012-10-01

Full Text Available The direct combination of a photovoltaic system with an energy storage component appears desirable since it produces and stores electrical energy simultaneously, enabling it to compensate power generation fluctuations and supply sufficient energy during low- or non-irradiation periods. A novel concept based on hydrogenated amorphous silicon (a-Si:H triple-junction solar cells, as for example a-Si:H/a-SiGe:H/a-SiGe:H, and a solar water splitting system integrating a polymer electrolyte membrane (PEM electrolyser is presented. The thin film layer-by-layer concept allows large-area module fabrication applicable to buildings, and exhibits strong cost-reduction potential as compared to similar concepts. The evaluation shows that it is possible to achieve a sufficient voltage of greater than 1.5 V for effective water splitting with the a-Si based solar cell. Nevertheless, in the case of grid-connection, the actual energy production cost for hydrogen storage by the proposed system is currently too high.

Generation IV nuclear energy systems and hydrogen economy. New progress in the energy field in the 21st century

International Nuclear Information System (INIS)

Zang Mingchang

2004-01-01

The concept of hydrogen economy was initiated by the United States and other developed countries in the turn of the century to mitigate anxiety of national security due to growing dependence on foreign sources of energy and impacts on air quality and the potential effects of greenhouse gas emissions. Hydrogen economy integrates the primary energy used to produce hydrogen as a future energy carrier, hydrogen technologies including production, delivery and storage, and various fuel cells for transportation and stationary applications. A new hydrogen-based energy system would created as an important solution in the 21st century, flexible, affordable, safe, domestically produced, used in all sectors of the economy and in all regions of the country, if all the R and D plans and the demonstration come to be successful in 20-30 years. Among options of primary energy. Generation IV nuclear energy under development is particularly well suited to hydrogen production, offering the competitive position of large-scale hydrogen production with near-zero emissions. (author)

Carbon-supported cobalt catalyst for hydrogen generation from alkaline sodium borohydride solution

Energy Technology Data Exchange (ETDEWEB)

Xu, Dongyan; Liu, Xinmin; Cao, Changqing; Guo, Qingjie [College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China); Dai, Ping [College of Electromechanical Engineering, Qingdao University of Science and Technology, Qingdao 266061 (China)

2008-08-01

Low cost transition metal catalysts with high performance are attractive for the development of on-board hydrogen generation systems by catalytic hydrolysis of sodium borohydride (NaBH{sub 4}) in fuel cell fields. In this study, hydrogen production from alkaline NaBH{sub 4} via hydrolysis process over carbon-supported cobalt catalysts was studied. The catalytic activity of the supported cobalt catalyst was found to be highly dependent on the calcination temperatures. The hydrogen generation rate increases with calcination temperatures in the range of 200-400 C, but a high calcination temperature above 500 C led to markedly decreased activity. X-ray diffraction patterns reveal that the catalysts experience phase transition from amorphous Co-B to crystalline cobalt hydroxide with increase in calcination temperatures. The reaction performance is also dependent on the concentration of NaBH{sub 4}, and the hydrogen generation rate increases for lower NaBH{sub 4} concentrations and decreases after reaching a maximum at 10 wt.% of NaBH{sub 4}. (author)

Present status of research on hydrogen energy and perspective of HTGR hydrogen production system

Energy Technology Data Exchange (ETDEWEB)

Miyamoto, Yoshiaki; Ogawa, Masuro; Akino, Norio [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment] [and others

2001-03-01

A study was performed to make a clear positioning of research and development on hydrogen production systems with a High Temperature Gas-cooled Reactor (HTGR) under currently promoting at the Japan Atomic Energy Research Institute through a grasp of the present status of hydrogen energy, focussing on its production and utilization as an energy in future. The study made clear that introduction of safe distance concept for hydrogen fire and explosion was practicable for a HTGR hydrogen production system, including hydrogen properties and need to provide regulations applying to handle hydrogen. And also generalization of hydrogen production processes showed technical issues of the HTGR system. Hydrogen with HTGR was competitive to one with fossil fired system due to evaluation of production cost. Hydrogen is expected to be used as promising fuel of fuel cell cars in future. In addition, the study indicated that there were a large amount of energy demand alternative to high efficiency power generation and fossil fuel with nuclear energy through the structure of energy demand and supply in Japan. Assuming that hydrogen with HTGR meets all demand of fuel cell cars, an estimation would show introduction of the maximum number of about 30 HTGRs with capacity of 100 MWt from 2020 to 2030. (author)

Hydrogen Fuel Cell Analysis: Lessons Learned from Stationary Power Generation Final Report

Energy Technology Data Exchange (ETDEWEB)

Scott E. Grasman; John W. Sheffield; Fatih Dogan; Sunggyu Lee; Umit O. Koylu; Angie Rolufs

2010-04-30

This study considered opportunities for hydrogen in stationary applications in order to make recommendations related to RD&D strategies that incorporate lessons learned and best practices from relevant national and international stationary power efforts, as well as cost and environmental modeling of pathways. The study analyzed the different strategies utilized in power generation systems and identified the different challenges and opportunities for producing and using hydrogen as an energy carrier. Specific objectives included both a synopsis/critical analysis of lessons learned from previous stationary power programs and recommendations for a strategy for hydrogen infrastructure deployment. This strategy incorporates all hydrogen pathways and a combination of distributed power generating stations, and provides an overview of stationary power markets, benefits of hydrogen-based stationary power systems, and competitive and technological challenges. The motivation for this project was to identify the lessons learned from prior stationary power programs, including the most significant obstacles, how these obstacles have been approached, outcomes of the programs, and how this information can be used by the Hydrogen, Fuel Cells & Infrastructure Technologies Program to meet program objectives primarily related to hydrogen pathway technologies (production, storage, and delivery) and implementation of fuel cell technologies for distributed stationary power. In addition, the lessons learned address environmental and safety concerns, including codes and standards, and education of key stakeholders.

Alkali free hydrolysis of sodium borohydride for hydrogen generation under pressure

Energy Technology Data Exchange (ETDEWEB)

Ferreira, M.J.F.; Pinto, A.M.F.R. [Centro de Estudos de Fenomenos de Transporte, Departamento de Engenharia Quimica, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias s/n, 4200-465 Porto (Portugal); Gales, L. [Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto and Instituto de Ciencias Biomedicas Abel Salazar, Largo Prof. Abel Salazar 2, 4099-003 Porto (Portugal); Fernandes, V.R.; Rangel, C.M. [Laboratorio Nacional de Energia e Geologia - LNEG, Fuel Cells and Hydrogen Unit Estrada do Paco do Lumiar 22, 1649-038 Lisboa (Portugal)

2010-09-15

The present study is related with the production of hydrogen gas (H{sub 2}), at elevated pressures and with high gravimetric storage density, to supply a PEM fuel cell on-demand. To achieve this goal, solid sodium borohydride (NaBH{sub 4}) was mixed with a proper amount of a powder reused nickel-ruthenium based catalyst (Ni-Ru based/NaBH{sub 4}: 0.2 and 0.4 g/g; {approx}150 times reused) inside the bottom of a batch reactor. Then, a stoichiometric amount of pure liquid water (H{sub 2}O/NaBH{sub 4}: 2-8 mol/mol) was added and the catalyzed NaBH{sub 4} hydrolysis evolved, in the absence of an alkali inhibitor. In this way, this research work is designated alkali free hydrolysis of NaBH{sub 4} for H{sub 2} generation. This type of hydrolysis is excellent from an environmental point of view because it does not involve strongly caustic solutions. Experiments were performed in three batch reactors with internal volumes 646, 369 and 229 cm{sup 3}, and having different bottom geometries (flat and conical shapes). The H{sub 2} generated was a function of the added water and completion was achieved with H{sub 2}O/NaBH{sub 4} = 8 mol/mol. The results show that hydrogen yields and rates increase remarkably increasing both system temperature and pressure. Reactor bottom shape influences deeply H{sub 2} generation: the conical bottom shape greatly enhances the rate and practically eliminates the reaction induction time. Our system of compressed hydrogen generation up to 1.26 MPa shows 6.3 wt% and 70 kg m{sup -3}, respectively, for gravimetric and volumetric hydrogen storage capacities (materials-only basis) and therefore is a viable hydrogen storage candidate for portable applications. (author)

Case Studies of integrated hydrogen systems. International Energy Agency Hydrogen Implementing Agreement, Final report for Subtask A of task 11 - Integrated Systems

Energy Technology Data Exchange (ETDEWEB)

Schucan, T. [Paul Scherrer Inst., Villigen PSI (Switzerland)

1999-12-31

Within the framework of the International Energy Agency Hydrogen Implementing Agreement, Task 11 was undertaken to develop tools to assist in the design and evaluation of existing and potential hydrogen demonstration projects. Emphasis was placed on integrated systems, from input energy to hydrogen end use. Included in the PDF document are the Executive Summary of the final report and the various case studies. The activities of task 11 were focused on near- and mid-term applications, with consideration for the transition from fossil-based systems to sustainable hydrogen energy systems. The participating countries were Canada, Italy, Japan, the Netherlands, Spain, Switzerland and the United States. In order for hydrogen to become a competitive energy carrier, experience and operating data need to be generated and collected through demonstration projects. A framework of scientific principles, technical expertise, and analytical evaluation and assessment needed to be developed to aid in the design and optimization of hydrogen demonstration projects to promote implementation. The task participants undertook research within the framework of three highly coordinated subtasks that focused on the collection and critical evaluation of data from existing demonstration projects around the world, the development and testing of computer models of hydrogen components and integrated systems, and the evaluation and comparison of hydrogen systems. While the Executive Summary reflects work on all three subtasks, this collection of chapters refers only to the work performed under Subtask A. Ten projects were analyzed and evaluated in detail as part of Subtask A, Case Studies. The projects and the project partners were: Solar Hydrogen Demonstration Project, Solar-Wasserstoff-Bayern, Bayernwerk, BMW, Linde, Siemens (Germany); Solar Hydrogen Plant on Residential House, M. Friedli (Switzerland); A.T. Stuart Renewable Energy Test Site; Stuart Energy Systems (Canada); PHOEBUS Juelich

Alternative Energetics DC Microgrid With Hydrogen Energy Storage System

Directory of Open Access Journals (Sweden)

Zaļeskis Genadijs

2016-12-01

Full Text Available This paper is related to an alternative energetics microgrid with a wind generator and a hydrogen energy storage system. The main aim of this research is the development of solutions for effective use of the wind generators in alternative energetics devices, at the same time providing uninterrupted power supply of the critical loads. In this research, it was accepted that the alternative energetics microgrid operates in an autonomous mode and the connection to the conventional power grid is not used. In the case when wind speed is low, the necessary power is provided by the energy storage system, which includes a fuel cell and a tank with stored hydrogen. The theoretical analysis of the storage system operation is made. The possible usage time of the stored hydrogen depends on the available amount of hydrogen and the consumption of the hydrogen by the fuel cell. The consumption, in turn, depends on used fuel cell power. The experimental results suggest that if the wind generator can provide only a part of the needed power, the abiding power can be provided by the fuel cell. In this case, a load filter is necessary to decrease the fuel cell current pulsations.

Analysis of Hydrogen Generation and Accumulation in U-233 Tube Vaults

International Nuclear Information System (INIS)

Ally, M.R.; Willis, K.J.

1999-01-01

The purpose of the 233 U Safe Storage Program is to enhance the safe storage of 233 U-bearing materials. This report describes the work done at the Oak Ridge National Laboratory's Radiochemical Development Facility (RDF) to address questions related to possible hydrogen generation and accumulation in 233 U tube vaults. The objective of this effort was to verify assumptions in the mathematical model used to estimate the hydrogen content of the gaseous atmosphere that possibly could occur inside the tube vaults in Building 3019 and to evaluate proposed measures for mitigating any hydrogen concerns. A mathematical model was developed using conservative assumptions to evaluate possible hydrogen generation and accumulation in the tube vaults. The model concluded that an equilibrium concentration would be established below the lower flammability limit (LFL) of 4.1% hydrogen. The major assumptions used in the model that were validated are as follows: (1) The shield plug does not form a seal with the tube vault wall, thus allowing the hydrogen gas to diffuse past the shield plug to the upper section of the tube vault. (2) The tube vault end-cap leaks sufficiently to allow air to be drawn into the tube vault by the off-gas system, thereby purging hydrogen from the upper section of the tube vault. (3) Any hydrogen gas generated completely mixes with the other gases present in the lower section of the tube vault and does not stratify beneath the shield plug. (4) The diffusion coefficient determined from the literature for constant diffusion of hydrogen in air is valid. The coefficient is corrected for temperatures from 0 to 25 C. Another assumption used in the model, that hydrogen generated by radiolytic decomposition of hydrogen-bearing materials (e.g., moisture and plastic) leaks from the cans under steady-state condition, as opposed to a sudden release resulting from rupture of the can(s), was beyond the scope of this investigation. Several parameters from the original

Methods and systems for the production of hydrogen

Science.gov (United States)

Oh, Chang H [Idaho Falls, ID; Kim, Eung S [Ammon, ID; Sherman, Steven R [Augusta, GA

2012-03-13

Methods and systems are disclosed for the production of hydrogen and the use of high-temperature heat sources in energy conversion. In one embodiment, a primary loop may include a nuclear reactor utilizing a molten salt or helium as a coolant. The nuclear reactor may provide heat energy to a power generation loop for production of electrical energy. For example, a supercritical carbon dioxide fluid may be heated by the nuclear reactor via the molten salt and then expanded in a turbine to drive a generator. An intermediate heat exchange loop may also be thermally coupled with the primary loop and provide heat energy to one or more hydrogen production facilities. A portion of the hydrogen produced by the hydrogen production facility may be diverted to a combustor to elevate the temperature of water being split into hydrogen and oxygen by the hydrogen production facility.

Novel, Ceramic Membrane System For Hydrogen Separation

Energy Technology Data Exchange (ETDEWEB)

Elangovan, S.

2012-12-31

Separation of hydrogen from coal gas represents one of the most promising ways to produce alternative sources of fuel. Ceramatec, teamed with CoorsTek and Sandia National Laboratories has developed materials technology for a pressure driven, high temperature proton-electron mixed conducting membrane system to remove hydrogen from the syngas. This system separates high purity hydrogen and isolates high pressure CO{sub 2} as the retentate, which is amenable to low cost capture and transport to storage sites. The team demonstrated a highly efficient, pressure-driven hydrogen separation membrane to generate high purity hydrogen from syngas using a novel ceramic-ceramic composite membrane. Recognizing the benefits and limitations of present membrane systems, the all-ceramic system has been developed to address the key technical challenges related to materials performance under actual operating conditions, while retaining the advantages of thermal and process compatibility offered by the ceramic membranes. The feasibility of the concept has already been demonstrated at Ceramatec. This project developed advanced materials composition for potential integration with water gas shift rectors to maximize the hydrogenproduction.

Economic Efficiency Assessment of Autonomous Wind/Diesel/Hydrogen Systems in Russia

Directory of Open Access Journals (Sweden)

O. V. Marchenko

2013-01-01

Full Text Available The economic efficiency of harnessing wind energy in the autonomous power systems of Russia is analyzed. Wind turbines are shown to be competitive for many considered variants (groups of consumers, placement areas, and climatic and meteorological conditions. The authors study the possibility of storing energy in the form of hydrogen in the autonomous wind/diesel/hydrogen power systems that include wind turbines, diesel generator, electrolyzer, hydrogen tank, and fuel cells. The paper presents the zones of economic efficiency of the system (set of parameters that provide its competitiveness depending on load, fuel price, and long-term average annual wind speed. At low wind speed and low price of fuel, it is reasonable to use only diesel generator to supply power to consumers. When the fuel price and wind speed increase, first it becomes more economical to use a wind-diesel system and then wind turbines with a hydrogen system. In the latter case, according to the optimization results, diesel generator is excluded from the system.

Generation of hydrogen free radicals from water for fuels by electric field induction

International Nuclear Information System (INIS)

Nong, Guangzai; Chen, Yiyi; Li, Ming; Zhou, Zongwen

2015-01-01

Highlights: • Hydrogen free radicals are generated from water splitting. • Hydrogen fuel is generated from water by electric field induction. • Hydrocarbon fuel is generated from CO_2 and water by electric field induction. - Abstract: Water is the most abundant resource for generating hydrogen fuel. In addition to dissociating H"+ and "−OH ions, certain water molecules dissociate to radicals under an electric field are considered. Therefore, an electric field inducing reactor is constructed and operated to generate hydrogen free radicals in this paper. Hydrogen free radicals begin to be generated under a 1.0 V electric field, and increasing the voltage and temperature increases the number of hydrogen free radicals. The production rate of hydrogen free radicals is 0.245 mmol/(L h) at 5.0 V and room temperature. The generated hydrogen free radicals are converted to polymer fuel and hydrogen fuel at production rates of 0.0093 mmol/(L h) and 0.0038 mmol/(L h) respectively, under 5.0 V and 0.25 mA. The results provide a way to generate hydrogen free radicals, which might be used to generate hydrocarbon fuel in industrial manufacture.

Hydrolysis Batteries: Generating Electrical Energy during Hydrogen Absorption.

Science.gov (United States)

Xiao, Rui; Chen, Jun; Fu, Kai; Zheng, Xinyao; Wang, Teng; Zheng, Jie; Li, Xingguo

2018-02-19

The hydrolysis reaction of aluminum can be decoupled into a battery by pairing an Al foil with a Pd-capped yttrium dihydride (YH 2 -Pd) electrode. This hydrolysis battery generates a voltage around 0.45 V and leads to hydrogen absorption into the YH 2 layer. This represents a new hydrogen absorption mechanism featuring electrical energy generation during hydrogen absorption. The hydrolysis battery converts 8-15 % of the thermal energy of the hydrolysis reaction into usable electrical energy, leading to much higher energy efficiency compared to that of direct hydrolysis. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hydrogen Generation From Electrolysis

Energy Technology Data Exchange (ETDEWEB)

Steven Cohen; Stephen Porter; Oscar Chow; David Henderson

2009-03-06

Small-scale (100-500 kg H2/day) electrolysis is an important step in increasing the use of hydrogen as fuel. Until there is a large population of hydrogen fueled vehicles, the smaller production systems will be the most cost-effective. Performing conceptual designs and analyses in this size range enables identification of issues and/or opportunities for improvement in approach on the path to 1500 kg H2/day and larger systems. The objectives of this program are to establish the possible pathways to cost effective larger Proton Exchange Membrane (PEM) water electrolysis systems and to identify areas where future research and development efforts have the opportunity for the greatest impact in terms of capital cost reduction and efficiency improvements. System design and analysis was conducted to determine the overall electrolysis system component architecture and develop a life cycle cost estimate. A design trade study identified subsystem components and configurations based on the trade-offs between system efficiency, cost and lifetime. Laboratory testing of components was conducted to optimize performance and decrease cost, and this data was used as input to modeling of system performance and cost. PEM electrolysis has historically been burdened by high capital costs and lower efficiency than required for large-scale hydrogen production. This was known going into the program and solutions to these issues were the focus of the work. The program provided insights to significant cost reduction and efficiency improvement opportunities for PEM electrolysis. The work performed revealed many improvement ideas that when utilized together can make significant progress towards the technical and cost targets of the DOE program. The cell stack capital cost requires reduction to approximately 25% of today’s technology. The pathway to achieve this is through part count reduction, use of thinner membranes, and catalyst loading reduction. Large-scale power supplies are available

Universally applicable design concept of stably controlling an HTGR-hydrogen production system

International Nuclear Information System (INIS)

Hada, Kazuhiko; Shibata, Taiju; Nishihara, Tetsuo; Shiozawa, Shusaku

1996-01-01

An HTGR-hydrogen production system should be designed to have stable controllability because of a large difference in thermal dynamics between reactor and hydrogen production system and such a control design concept should be universally applicable to a variety of hydrogen production processes by the use of nuclear heat from HTGR. A transient response analysis of an HTGR-steam reforming hydrogen production system showed that a steam generator installed in a helium circuit for cooling the nuclear reactor provides stable controllability of the total system, resulting in avoiding a reactor scram. A survey of control design-related characteristics among several hydrogen production processes revealed the similarity of endothermic chemical reactions by the use of high temperature heat and that steam is required as a reactant of the endothermic reaction or for preheating a reactant. Based on these findings, a system design concept with stable controllability and universal applicability was proposed to install a steam generator as a downstream cooler of an endothermic reactor in the helium circuit of an HTGR-hydrogen production system. (author)

CHALLENGES IN GENERATING HYDROGEN BY HIGH TEMPERATURE ELECTROLYSIS USING SOLID OXIDE CELLS

Energy Technology Data Exchange (ETDEWEB)

M. S. Sohal; J. E. O' Brien; C. M. Stoots; M. G. McKellar; J. S. Herring; E. A. Harvego

2008-03-01

Idaho National Laboratory’s (INL) high temperature electrolysis research to generate hydrogen using solid oxide electrolysis cells is presented in this paper. The research results reported here have been obtained in a laboratory-scale apparatus. These results and common scale-up issues also indicate that for the technology to be successful in a large industrial setting, several technical, economical, and manufacturing issues have to be resolved. Some of the issues related to solid oxide cells are stack design and performance optimization, identification and evaluation of cell performance degradation parameters and processes, integrity and reliability of the solid oxide electrolysis (SOEC) stacks, life-time prediction and extension of the SOEC stack, and cost reduction and economic manufacturing of the SOEC stacks. Besides the solid oxide cells, balance of the hydrogen generating plant also needs significant development. These issues are process and ohmic heat source needed for maintaining the reaction temperature (~830°C), high temperature heat exchangers and recuperators, equal distribution of the reactants into each cell, system analysis of hydrogen and associated energy generating plant, and cost optimization. An economic analysis of this plant was performed using the standardized H2A Analysis Methodology developed by the Department of Energy (DOE) Hydrogen Program, and using realistic financial and cost estimating assumptions. The results of the economic analysis demonstrated that the HTE hydrogen production plant driven by a high-temperature helium-cooled nuclear power plant can deliver hydrogen at a cost of $3.23/kg of hydrogen assuming an internal rate of return of 10%. These issues need interdisciplinary research effort of federal laboratories, solid oxide cell manufacturers, hydrogen consumers, and other such stakeholders. This paper discusses research and development accomplished by INL on such issues and highlights associated challenges that need to

Hydrogen generation behaviors of NaBH4-NH3BH3 composite by hydrolysis

Science.gov (United States)

Xu, Yanmin; Wu, Chaoling; Chen, Yungui; Huang, Zhifen; Luo, Linshan; Wu, Haiwen; Liu, Peipei

2014-09-01

In this work, NH3BH3 (AB) is used to induce hydrogen generation during NaBH4 (SB) hydrolysis in order to reduce the use of catalysts, simplify the preparation process, reduce the cost and improve desorption kinetics and hydrogen capacity as well. xNaBH4-yNH3BH3 composites are prepared by ball-milling in different proportions (from x:y = 1:1 to 8:1). The experimental results demonstrate that all composites can release more than 90% of hydrogen at 70 °C within 1 h, and their hydrogen yields can reach 9 wt% (taking reacted water into account). Among them, the composites in the proportion of 4:1 and 5:1, whose hydrogen yields reach no less than 10 wt%, show the best hydrogen generation properties. This is due to the impact of the following aspects: AB additive improves the dispersibility of SB particles, makes the composite more porous, hampers the generated metaborate from adhering to the surface of SB, and decreases the pH value of the composite during hydrolysis. The main solid byproduct of this hydrolysis system is NaBO2·2H2O. By hydrolytic kinetic simulation of the composites, the fitted activation energies of the complexes are between 37.2 and 45.6 kJ mol-1, which are comparable to the catalytic system with some precious metals and alloys.

Interfacial electrochemistry of colloidal ruthenium dioxide and catalysis of the photochemical generation of hydrogen from water

NARCIS (Netherlands)

Kleijn, J.M.

1987-01-01

The formation of hydrogen from water using solar energy is a very attractive research topic, because of the potential use of hydrogen as an alternative, clean fuel. It has been shown by many workers in the field that photochemical hydrogen generation can be achieved in an aqueous system,

Air-stable hydrogen generation materials and enhanced hydrolysis performance of MgH2-LiNH2 composites

Science.gov (United States)

Ma, Miaolian; Ouyang, Liuzhang; Liu, Jiangwen; Wang, Hui; Shao, Huaiyu; Zhu, Min

2017-08-01

Hydrolysis of materials in water can be a promising solution of onsite hydrogen generation for realization of hydrogen economy. In this work, it was the first time that the MgH2-LiNH2 composites were explored as air-stable hydrolysis system for hydrogen generation. The MgH2-LiNH2 composites with different composition ratios were synthesized by ball milling with various durations and the hydrogen generation performances of the composite samples were investigated and compared. X-ray diffraction, X-ray photoelectron spectroscopy and scanning electron microscopy techniques were adopted to elucidate the performance improvement mechanisms. The hydrolysis properties of MgH2 were found to be significantly enhanced by the introduction of LiNH2. The 4MgH2-LiNH2 composite ball milled for 5 h can generate 887.2 mL g-1 hydrogen in 1 min and 1016 mL g-1 in 50 min, one of the best results so far for Mg based hydrolysis materials. The LiOH·H2O and NH4OH phases of hydrolysis products from LiNH2 may prevent formation of Mg(OH)2 passivation layer on the surface and supply enough channels for hydrolysis of MgH2. The MgH2-LiNH2 composites appeared to be very stable in air and no obvious negative effect on kinetics and hydrogen generation yield was observed. These good performances demonstrate that the studied MgH2-LiNH2 composites can be a promising and practicable hydrogen generation system.

System optimization of solar hydrogen energy system based on hydrogen production cost. 2; Suiso seizo cost wo hyoka shihyo to shita taiyo suiso energy system no saiteki sekkei. 2

Energy Technology Data Exchange (ETDEWEB)

Ota, D; Yamagami, Y; Tani, T [Science University of Tokyo, Tokyo (Japan)

1996-10-27

In this paper, to evaluate the hydrogen production cost per unit volume, system optimization of solar hydrogen energy system is discussed. Based on the simulation of the I-V characteristics of amorphous Si (a-Si) photovoltaic array, the working point between the array and hydrogen generator was determined. The cost ratio of each design point was calculated. The optimum design points were 500 W/m{sup 2} for the single crystal Si system, and 600 W/m{sup 2} for the a-Si system. When the rating capacity of design point was constant, almost constant cost ratio was obtained independent of the type of photovoltaic cells. It was found that the photovoltaic cells can be fabricated in about 15% lower cost at maximum. It was also found that the optimum design point sifts to the lower insolation site due to reduction of the photovoltaic cell cost. Since the annual hydrogen generation quantity does not depend on the type of photovoltaic cells under the constant rating capacity of design point, hydrogen can be produced in lower cost by using photovoltaic cell of lower cost. 5 refs., 10 figs., 5 tabs.

Hydrogen-metal systems

International Nuclear Information System (INIS)

Wenzl, H.; Springer, T.

1976-01-01

A survey is given on the alloys of metal crystals with hydrogen. The system niobium-hydrogen and its properties are especially dealt with: diffusion and heat of solution of hydrogen in the host crystal, phase diagram, coherent and incoherent phase separation, application of metal-hydrogen systems in technology. Furthermore, examples from research work in IFF (Institut fuer Festkoerperforschung) of the Nuclear Research Plant, Juelich, in the field of metal-H systems are given in summary form. (GSC) [de

Advanced chemical hydride-based hydrogen generation/storage system for fuel cell vehicles

Energy Technology Data Exchange (ETDEWEB)

Breault, R.W.; Rolfe, J. [Thermo Power Corp., Waltham, MA (United States)

1998-08-01

Because of the inherent advantages of high efficiency, environmental acceptability, and high modularity, fuel cells are potentially attractive power supplies. Worldwide concerns over clean environments have revitalized research efforts on developing fuel cell vehicles (FCV). As a result of intensive research efforts, most of the subsystem technology for FCV`s are currently well established. These include: high power density PEM fuel cells, control systems, thermal management technology, and secondary power sources for hybrid operation. For mobile applications, however, supply of hydrogen or fuel for fuel cell operation poses a significant logistic problem. To supply high purity hydrogen for FCV operation, Thermo Power`s Advanced Technology Group is developing an advanced hydrogen storage technology. In this approach, a metal hydride/organic slurry is used as the hydrogen carrier and storage media. At the point of use, high purity hydrogen will be produced by reacting the metal hydride/organic slurry with water. In addition, Thermo Power has conceived the paths for recovery and regeneration of the spent hydride (practically metal hydroxide). The fluid-like nature of the spent hydride/organic slurry will provide a unique opportunity for pumping, transporting, and storing these materials. The final product of the program will be a user-friendly and relatively high energy storage density hydrogen supply system for fuel cell operation. In addition, the spent hydride can relatively easily be collected at the pumping station and regenerated utilizing renewable sources, such as biomass, natural, or coal, at the central processing plants. Therefore, the entire process will be economically favorable and environmentally friendly.

Nickel Hydrogen Battery Expert System

Science.gov (United States)

Johnson, Yvette B.; Mccall, Kurt E.

1992-01-01

The Nickel Cadmium Battery Expert System-2, or 'NICBES-2', which was used by the NASA HST six-battery testbed, was subsequently converted into the Nickel Hydrogen Battery Expert System, or 'NICHES'. Accounts are presently given of this conversion process and future uses being contemplated for NICHES. NICHES will calculate orbital summary data at the end of each orbit, and store these files for trend analyses and rules-generation.

Hydrogen-oxygen steam generator applications for increasing the efficiency, maneuverability and reliability of power production

Science.gov (United States)

Schastlivtsev, A. I.; Borzenko, V. I.

2017-11-01

The comparative feasibility study of the energy storage technologies showed good applicability of hydrogen-oxygen steam generators (HOSG) based energy storage systems with large-scale hydrogen production. The developed scheme solutions for the use of HOSGs for thermal power (TPP) and nuclear power plants (NPP), and the feasibility analysis that have been carried out have shown that their use makes it possible to increase the maneuverability of steam turbines and provide backup power supply in the event of failure of the main steam generating equipment. The main design solutions for the integration of hydrogen-oxygen steam generators into the main power equipment of TPPs and NPPs, as well as their optimal operation modes, are considered.

Hydrogen production system coupled with high-temperature gas-cooled reactor (HTTR)

International Nuclear Information System (INIS)

Shiozawa, Shusaku

2003-01-01

On the HTTR program, R and D on nuclear reactor technology and R and D on thermal application technology such as hydrogen production and so on, are advanced. When carrying out power generation and thermal application such as hydrogen production and so on, it is, at first, necessary to supply nuclear heat safely, stably and in low cost, JAERI carries out some R and Ds on nuclear reactor technology using HTTR. In parallel to this, JAERI also carries out R and D for jointing nuclear reactor system with thermal application systems because of no experience in the world on high temperature heat of about 1,000 centigrade supplied by nuclear reactor except power generation, and R and D on thermochemical decomposition method IS process for producing hydrogen from water without exhaust of carbon dioxide. Here were described summaries on R and D on nuclear reactor technology, R and D on jointing technology using HTTR hydrogen production system, R and D on IS process hydrogen production, and comparison hydrogen production with other processes. (G.K.)

Integrated energy systems for hydrogen and electricity supply

Energy Technology Data Exchange (ETDEWEB)

Muradov, N. [Univ. of Central Florida, Cocoa, FL (United States). Florida Solar Energy Center; Manikowski, A.; Noland, G. [Procyon Power Systems Inc., Alameda, CA (United States)

2002-07-01

The United States will soon need an increase in electric generating capacity along with an increase in the distribution capacity of the electricity grid. The cost and time required to build additional electrical distribution and transmission systems can be avoided by using distributed power generation. This paper examines the development of an integrated stand-alone energy system that can produce hydrogen, electricity and heat. The concept is based on integrated operation of a thermocatalytic pyrolysis (TCP) reactor and a solid oxide fuel cell (SOFC). The benefits include high overall energy efficiency, the production of high quality hydrogen (90 to 95 per cent free of carbon oxides), low emissions, and fuel flexibility. Experimental data is presented regarding the thermocatalytic pyrolysis of methane compared with an iron-based catalyst (which is sulfur resistant) and gasification of the resulting carbon with steam and carbon dioxide. With distributed generation, additional electrical generating capacity can be added in small increments distributed over the grid. An integrated energy system will be applicable to any type of hydrocarbon fuel, such as natural gas, liquid propane gas, gasoline, kerosene, jet fuel, diesel fuel and sulfurous residual oils. The suitable range of operating parameters needed to decoke a catalyst bed using steam and carbon dioxide as a degasifying agent was also determined. The Fe-catalyst was efficient in both methane pyrolysis and steam/CO{sub 2} gasification of carbon. It was shown that the TCP and SOFC complement each other in may ways. With the IES, high quality hydrogen is delivered to the end user. IES can also operate as either a hydrogen production unit or as an electrical power generator. The energy efficiency of the IES is estimated at 45-55 per cent. 6 refs., 8 figs.

Study on commercial HTGR hydrogen production system

International Nuclear Information System (INIS)

Nishihara, Tetsuo

2000-07-01

The Japanese energy demand in 2030 will increase up to 117% in comparison with one in 2000. We have to avoid a large consumption of fossil fuel that induces a large CO 2 emission from viewpoint of global warming. Furthermore new energy resources expected to resolve global warming have difficulty to be introduced more because of their low energy density. As a result, nuclear power still has a possibility of large introduction to meet the increasing energy demand. On the other hand, in Japan, 40% of fossil fuels in the primary energy are utilized for power generation, and the remaining are utilized as a heat source. New clean energy is required to reduce the consumption of fossil fuels and hydrogen is expected as a alternative energy resource. Prediction of potential hydrogen demand in Japan is carried out and it is clarified that the demand will potentially increase up to 4% of total primary energy in 2050. In present, steam reforming method is the most economical among hydrogen generation processes and the cost of hydrogen production is about 7 to 8 yen/m 3 in Europe and the United States and about 13 yen/m 3 in Japan. JAERI has proposed for using the HTGR whose maximum core outlet temperature is at 950degC as a heat source in the steam reforming to reduced the consumption of fossil fuels and resulting CO 2 emission. Based on the survey of the production rate and the required thermal energy in conventional industry, it is clarified that a hydrogen production system by the steam reforming is the best process for the commercial HTGR nuclear heat utilization. The HTGR steam reforming system and other candidate nuclear heat utilization systems are considered from viewpoint of system layout and economy. From the results, the hydrogen production cost in the HTGR stream reforming system is expected to be about 13.5 yen/m 3 if the cost of nuclear heat of the HTGR is the same as one of the LWR. (author)

Next Generation Nuclear Plant System Requirements Manual

International Nuclear Information System (INIS)

Not Listed

2008-01-01

System Requirements Manual for the NGNP Project. The Energy Policy Act of 2005 (H.R. 6; EPAct), which was signed into law by President George W. Bush in August 2005, required the Secretary of the U.S. Department of Energy (DOE) to establish a project to be known as the Next Generation Nuclear Plant (NGNP) Project. According to the EPAct, the NGNP Project shall consist of the research, development, design, construction, and operation of a prototype plant (to be referred to herein as the NGNP) that (1) includes a nuclear reactor based on the research and development (R and D) activities supported by the Generation IV Nuclear Energy Systems initiative, and (2) shall be used to generate electricity, to produce hydrogen, or to both generate electricity and produce hydrogen. The NGNP Project supports both the national need to develop safe, clean, economical nuclear energy and the Nuclear Hydrogen Initiative (NHI), which has the goal of establishing greenhouse-gas-free technologies for the production of hydrogen. The DOE has selected the helium-cooled High Temperature Gas-Cooled Reactor (HTGR) as the reactor concept to be used for the NGNP because it is the only near-term Generation IV concept that has the capability to provide process heat at high-enough temperatures for highly efficient production of hydrogen. The EPAct also names the Idaho National Laboratory (INL), the DOE's lead national laboratory for nuclear energy research, as the site for the prototype NGNP

Hydrogen sulfide generation in shipboard oily-water waste. Part 3. Ship factors

Energy Technology Data Exchange (ETDEWEB)

Hodgeman, D.K.; Fletcher, L.E.; Upsher, F.J.

1995-04-01

The chemical and microbiological composition of bilge-water in ships of the Royal Australian Navy has been investigated in relation to the formation of hydrogen sulfide by sulfate-reducing bacteria. Sulfate-reducing bacteria were found in most ships in populations up to 800,000 per mL. Sulfate in the wastes is provided by sea-water. Sea-water constitutes up to 60% (median 20%) of the wastes analysed. Evidence for generation of hydrogen sulfide in the ships was found directly as sulfide or indirectly as depressed sulfate concentrations. The low levels of sulfide found in bilge-water from machinery spaces suggested the ventilation systems were effectively removing the gas from the working area. The effect of storage of the wastes under conditions which simulated the oily- water holding tanks of ships were also investigated. Some wastes were found to produce large quantities of hydrogen sulfide on storage. The wastes that failed to produce hydrogen sulfide were investigated to identify any specific nutritional deficiencies. Some organic substances present in bilge-water, such as lactate or biodegradable cleaning agents, and phosphate strongly influenced the generation of hydrogen sulfide in stored oily-water wastes.

Stand alone solution for generation and storage of hydrogen and electric energy

International Nuclear Information System (INIS)

Gany, Alon; Elitzur, Shani; Valery

2015-01-01

A novel method enabling safe, simple, and controllable production, storage, and use of hydrogen as well as compact electric energy storage and generation via hydrogen- oxygen fuel cells has been developed. The technology indicates, in our opinion, a significant milestone in the search for practical utilization of hydrogen as an alternative energy source. It consists of an original thermal-chemical treatment / activation of aluminum powders to react spontaneously with water to produce hydrogen at regular conditions according to the reaction Al+3H 2 O=Al (OH) 3 +3/2H 2 . Only about 1-2% of lithium, based activator is applied, and any type of water including tap water, sea water and waste water may be used, making the method attractive for variety of applications. 11% of hydrogen compared to the aluminum mass can be obtained, and our experiments reveal 90% reaction yield and more. The technology has a clear advantage over batteries, providing specific electric energy of over 2 kW h/kg Al, 5-10 times greater than that of commonly used lithium-ion batteries. Combined with a fuel cell it may be particularly beneficial for stand-alone electric power generators, where there is no access to the grid. Such applications include emergency generators (e.g., in hospitals), electricity backup systems, and power generation in remote communication posts. Automotive applications may be considered as well. The technology provides green electric energy and quiet operation as well as additional heat energy resulting mainly from the exothermic aluminum-water reaction. (full text)

Community Energy: Analysis of Hydrogen Distributed Energy Systems with Photovoltaics for Load Leveling and Vehicle Refueling

Energy Technology Data Exchange (ETDEWEB)

Steward, D.; Zuboy, J.

2014-10-01

Energy storage could complement PV electricity generation at the community level. Because PV generation is intermittent, strategies must be implemented to integrate it into the electricity system. Hydrogen and fuel cell technologies offer possible PV integration strategies, including the community-level approaches analyzed in this report: (1) using hydrogen production, storage, and reconversion to electricity to level PV generation and grid loads (reconversion scenario); (2) using hydrogen production and storage to capture peak PV generation and refuel hydrogen fuel cell electric vehicles (FCEVs) (hydrogen fueling scenario); and (3) a comparison scenario using a battery system to store electricity for EV nighttime charging (electric charging scenario).

Power generator system for HCL reaction

International Nuclear Information System (INIS)

Scragg, R. L.; Parker, A. B.

1984-01-01

A power generation system includes a nuclear reactor having a core which in addition to generating heat generates a high frequency electromagnetic radiation. An electromagnetic radiation chamber is positioned to receive at least a portion of the radiation generated by the reactor core. Hydrogen and chlorine are connected into the electromagnetic reactor chamber and react with controlled explosive violence when exposed to the radiation from the nuclear reactor. Oxygen is fed into the reactor chamber as a control medium. The resulting gases under high pressure and temperature are utilized to drive a gas turbine generators. In an alternative embodiment the highly ionized gases, hydrogen and chlorine are utilized as a fluid medium for use in magnetohydrodynamic generators which are attached to the electromagnetic reactor chambers

CO2-based hydrogen storage - Hydrogen generation from formaldehyde/water

Science.gov (United States)

Trincado, Monica; Grützmacher, Hansjörg; Prechtl, Martin H. G.

2018-04-01

Formaldehyde (CH2O) is the simplest and most significant industrially produced aldehyde. The global demand is about 30 megatons annually. Industrially it is produced by oxidation of methanol under energy intensive conditions. More recently, new fields of application for the use of formaldehyde and its derivatives as, i.e. cross-linker for resins or disinfectant, have been suggested. Dialkoxymethane has been envisioned as a combustion fuel for conventional engines or aqueous formaldehyde and paraformaldehyde may act as a liquid organic hydrogen carrier molecule (LOHC) for hydrogen generation to be used for hydrogen fuel cells. For the realization of these processes, it requires less energy-intensive technologies for the synthesis of formaldehyde. This overview summarizes the recent developments in low-temperature reductive synthesis of formaldehyde and its derivatives and low-temperature formaldehyde reforming. These aspects are important for the future demands on modern societies' energy management, in the form of a methanol and hydrogen economy, and the required formaldehyde feedstock for the manufacture of many formaldehyde-based daily products.

Anaerobic digestion for methane generation and ammonia reforming for hydrogen production: A thermodynamic energy balance of a model system to demonstrate net energy feasibility

International Nuclear Information System (INIS)

Babson, David M.; Bellman, Karen; Prakash, Shaurya; Fennell, Donna E.

2013-01-01

During anaerobic digestion, organic matter is converted to carbon dioxide and methane, and organic nitrogen is converted to ammonia. Generally, ammonia is recycled as a fertilizer or removed via nitrification–denitrification in treatment systems; alternatively it could be recovered and catalytically converted to hydrogen, thus supplying additional fuel. To provide a basis for further investigation, a theoretical energy balance for a model system that incorporates anaerobic digestion, ammonia separation and recovery, and conversion of the ammonia to hydrogen is reported. The model Anaerobic Digestion-Bioammonia to Hydrogen (ADBH) system energy demands including heating, pumping, mixing, and ammonia reforming were subtracted from the total energy output from methane and hydrogen to create an overall energy balance. The energy balance was examined for the ADBH system operating with a fixed feedstock loading rate with C:N ratios (gC/gN) ranging from 136 to 3 which imposed corresponding total ammonia nitrogen (TAN) concentrations of 20–10,000 mg/L. Normalizing total energy potential to the methane potential alone indicated that at a C:N ratio of 17, the energy output was greater for the ADBH system than from anaerobic digestion generating only methane. Decreasing the C:N ratio increased the methane content of the biogas comprising primarily methane to >80% and increased the ammonia stripping energy demand. The system required 23–34% of the total energy generated as parasitic losses with no energy integration, but when internally produced heat and pressure differentials were recovered, parasitic losses were reduced to between 8 and 17%. -- Highlights: •Modeled an integrated Anaerobic Digestion-Bioammonia to Hydrogen (ADBH) system. •Demonstrated positive net energy produced over a range of conditions by ADBH. •Demonstrated significant advantages of dual fuel recovery for energy gain by >20%. •Suggested system design considerations for energy recovery with

HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER

Energy Technology Data Exchange (ETDEWEB)

BROWN,LC; BESENBRUCH,GE; LENTSCH,RD; SCHULTZ,KR; FUNK,JF; PICKARD,PS; MARSHALL,AC; SHOWALTER,SK

2003-06-01

OAK B202 HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER. Combustion of fossil fuels, used to power transportation, generate electricity, heat homes and fuel industry provides 86% of the world's energy. Drawbacks to fossil fuel utilization include limited supply, pollution, and carbon dioxide emissions. Carbon dioxide emissions, thought to be responsible for global warming, are now the subject of international treaties. Together, these drawbacks argue for the replacement of fossil fuels with a less-polluting potentially renewable primary energy such as nuclear energy. Conventional nuclear plants readily generate electric power but fossil fuels are firmly entrenched in the transportation sector. Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. Hydrogen will be particularly advantageous when coupled with fuel cells. Fuel cells have higher efficiency than conventional battery/internal combustion engine combinations and do not produce nitrogen oxides during low-temperature operation. Contemporary hydrogen production is primarily based on fossil fuels and most specifically on natural gas. When hydrogen is produced using energy derived from fossil fuels, there is little or no environmental advantage. There is currently no large scale, cost-effective, environmentally attractive hydrogen production process available for commercialization, nor has such a process been identified. The objective of this work is to find an economically feasible process for the production of hydrogen, by nuclear means, using an advanced high-temperature nuclear reactor as the primary energy source. Hydrogen production by thermochemical water-splitting (Appendix A), a chemical process that accomplishes the decomposition of water into hydrogen and oxygen using only heat or, in the case of a hybrid thermochemical process, by a combination of heat and electrolysis, could meet these goals. Hydrogen produced from

Life cycle assessment of hydrogen production and fuel cell systems

International Nuclear Information System (INIS)

Dincer, I.

2007-01-01

This paper details life cycle assessment (LCA) of hydrogen production and fuel cell system. LCA is a key tool in hydrogen and fuel cell technologies for design, analysis, development; manufacture, applications etc. Energy efficiencies and greenhouse gases and air pollution emissions have been evaluated in all process steps including crude oil and natural gas pipeline transportation, crude oil distillation, natural gas reprocessing, wind and solar electricity generation , hydrogen production through water electrolysis and gasoline and hydrogen distribution and utilization

Potential of the HTGR hydrogen cogeneration system in Japan

International Nuclear Information System (INIS)

Nishihara, Tetsuo; Mouri, Tomoaki; Kunitomi, Kazuhiko

2007-01-01

A high temperature gas cooled reactor (HTGR) is one of the next generation nuclear systems. The HTGR hydrogen cogeneration system can produce not only electricity but also hydrogen. Then it has a potential to supply massive low-cost hydrogen without greenhouse gas emission for the future hydrogen society. Japan Atomic Energy Agency (JAEA) has been carried out the design study of the HTGR hydrogen cogeneration system (GTHTR300C). The thermal power of the reactor is 600 MW. The hydrogen production plant utilizes 370 MW and can supply 52,000 m 3 /h (0.4 Bm 3 /y) of hydrogen. Present industrial hydrogen production capacity in Japan is about 18 Bm 3 /y and it will decrease by 15 Bm 3 /y in 2030 due to the aging facilities. On the other hand, the hydrogen demand for fuel cell vehicle (FCV) in 2030 is estimated at 15 Bm 3 /y at a maximum. Since the hydrogen supply may be short after 2030, the additional hydrogen should be produced by clean hydrogen process to reduce greenhouse gas emission. This hydrogen shortage is a potential market for the GTHTR300C. The hydrogen production cost of GTHTR300C is estimated at 20.5 JPY/Nm 3 which has an economic competitiveness against other industrial hydrogen production processes. 38 units of the GTHTR300C can supply a half of this shortage which accounts for the 33% of hydrogen demand for FCV in 2100. According to the increase of hydrogen demand, the GTHTR300C should be constructed after 2030. (author)

Next-generation TCAP hydrogen isotope separation process

International Nuclear Information System (INIS)

Heung, L. K.; Sessions, H. T.; Poore, A. S.; Jacobs, W. D.; Williams, C. S.

2008-01-01

A thermal cycling absorption process (TCAP) for hydrogen isotope separation has been in operation at Savannah River Site since 1994. The process uses a hot/cold nitrogen system to cycle the temperature of the separation column. The hot/cold nitrogen system requires the use of large compressors, heat exchanges, valves and piping that is bulky and maintenance intensive. A new compact thermal cycling (CTC) design has recently been developed. This new design uses liquid nitrogen tubes and electric heaters to heat and cool the column directly so that the bulky hot/cold nitrogen system can be eliminated. This CTC design is simple and is easy to implement, and will be the next generation TCAP system at SRS. A twelve-meter column has been fabricated and installed in the laboratory to demonstrate its performance. The design of the system and its test results to date is discussed. (authors)

1 kWe sodium borohydride hydrogen generation system Part II: Reactor modeling

OpenAIRE

Zhang, Jinsong; Zheng, Yuan; Gore, Jay P; Mudawar, Issam; Fisher, Timothy

2007-01-01

Sodium borohydride (NaBH4) hydrogen storage systems offer many advantages for hydrogen storage applications. The physical processes inside a NaBH4 packed bed reactor involve multi-component and multi-phase flow and multi-mode heat and mass transfer. These processes are also coupled with reaction kinetics. To guide reactor design and optimization, a reactor model involving all of these processes is desired. A onedimensional numerical model in conjunction with the assumption of homogeneous cata...

Integrated Renewable Hydrogen Utility System (IRHUS) business plan

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

This business plan is for a proposed legal entity named IRHUS, Inc. which is to be formed as a subsidiary of Energy Partners, L.C. (EP) of West Palm Beach, Florida. EP is a research and development company specializing in hydrogen proton exchange membrane (PEM) fuel cells and systems. A fuel cell is an engine with no moving parts that takes in hydrogen and produces electricity. The purpose of IRHUS, Inc. is to develop and manufacture a self-sufficient energy system based on the fuel cell and other new technology that produces hydrogen and electricity. The product is called the Integrated renewable Hydrogen utility System (IRHUS). IRHUS, Inc. plans to start limited production of the IRHUS in 2002. The IRHUS is a unique product with an innovative concept in that it provides continuous electrical power in places with no electrical infrastructure, i.e., in remote and island locations. The IRHUS is a zero emissions, self-sufficient, hydrogen fuel generation system that produces electricity on a continuous basis by combining any renewable power source with hydrogen technology. Current plans are to produce a 10 kilowatt IRHUS MP (medium power). Future plans are to design and manufacture IRHUS models to provide power for a variety of power ranges for identified attractive market segments. The technological components of the IRHUS include an electrolyzer, hydrogen and oxygen storage subsystems, fuel cell system, and power control system. The IRHUS product is to be integrated with a variety of renewable energy technologies. 5 figs., 10 tabs.

Dye-Sensitized Photocatalytic Water Splitting and Sacrificial Hydrogen Generation: Current Status and Future Prospects

Directory of Open Access Journals (Sweden)

Pankaj Chowdhury

2017-05-01

Full Text Available Today, global warming and green energy are important topics of discussion for every intellectual gathering all over the world. The only sustainable solution to these problems is the use of solar energy and storing it as hydrogen fuel. Photocatalytic and photo-electrochemical water splitting and sacrificial hydrogen generation show a promise for future energy generation from renewable water and sunlight. This article mainly reviews the current research progress on photocatalytic and photo-electrochemical systems focusing on dye-sensitized overall water splitting and sacrificial hydrogen generation. An overview of significant parameters including dyes, sacrificial agents, modified photocatalysts and co-catalysts are provided. Also, the significance of statistical analysis as an effective tool for a systematic investigation of the effects of different factors and their interactions are explained. Finally, different photocatalytic reactor configurations that are currently in use for water splitting application in laboratory and large scale are discussed.

Hydrogen generation using silicon nanoparticles and their mixtures with alkali metal hydrides

Science.gov (United States)

Patki, Gauri Dilip

Hydrogen is a promising energy carrier, for use in fuel cells, engines, and turbines for transportation or mobile applications. Hydrogen is desirable as an energy carrier, because its oxidation by air releases substantial energy (thermally or electrochemically) and produces only water as a product. In contrast, hydrocarbon energy carriers inevitably produce CO2, contributing to global warming. While CO2 capture may prove feasible in large stationary applications, implementing it in transportation and mobile applications is a daunting challenge. Thus a zero-emission energy carrier like hydrogen is especially needed in these cases. Use of H2 as an energy carrier also brings new challenges such as safe handling of compressed hydrogen and implementation of new transport, storage, and delivery processes and infrastructure. With current storage technologies, hydrogen's energy per volume is very low compared to other automobile fuels. High density storage of compressed hydrogen requires combinations of high pressure and/or low temperature that are not very practical. An alternative for storage is use of solid light weight hydrogenous material systems which have long durability, good adsorption properties and high activity. Substantial research has been conducted on carbon materials like activated carbon, carbon nanofibers, and carbon nanotubes due to their high theoretical hydrogen capacities. However, the theoretical values have not been achieved, and hydrogen uptake capacities in these materials are below 10 wt. %. In this thesis we investigated the use of silicon for hydrogen generation. Hydrogen generation via water oxidation of silicon had been ignored due to slow reaction kinetics. We hypothesized that the hydrogen generation rate could be improved by using high surface area silicon nanoparticles. Our laser-pyrolysis-produced nanoparticles showed surprisingly rapid hydrogen generation and high hydrogen yield, exceeding the theoretical maximum of two moles of H2 per

Economically sustainable: market synergies in hydrogen systems

International Nuclear Information System (INIS)

Hart, D.

2000-01-01

As interest in the use of hydrogen as an energy carrier grows, it is important to understand the advantages and disadvantages of a market-based approach to its introduction. While there will always be niche markets in which it makes sense to employ what is currently a comparatively expensive form of energy storage and delivery, this will not enable the sort of large-scale penetration that will allow for economies of mass-manufacture to bring the cost of hydrogen down. In addition, energy markets are becoming increasingly liberalised, and because of this it is important to understand the sort of market pressures that are arising where none have existed before. These pressures may actually lead to opportunities for hydrogen in energy storage and for use in power generation and transport fuel modes, and allow market penetration to occur more rapidly than might be the case in a centralised energy structure. In the liberalised energy market within the UK, for example, there are two areas of potentially major growth in hydrogen production and consumption: energy storage for renewable generators; and backup systems at weak electricity grid links. The first of these is due, in part, to potential changes in regulation governing the way that electricity is sold into the market, while the second is dependent more on an increasingly congested electricity grid and the high costs of building supplementary infrastructure. In both cases there is potential for the early use of hydrogen energy systems in an economically competitive environment. (author)

Pec power generation system using pure energy

Energy Technology Data Exchange (ETDEWEB)

Tanaka, K; Sonai, A; Kano, A [Toshiba International Fuel Cells Corp. (Japan). Cell Technology Development Dept.; Yatake, T [Toshiba International Fuel Cells Corp. (Japan). Plant Engineering Dept.

2002-07-01

A polymer electrolyte fuel cell (PEFC) power generation system using pure hydrogen was developed by Toshiba International Fuel Cells (TIFC), Japan, under the sponsorship of the World Energy Network (WE-NET) Project. The goals of the project consist of the construction of 30 kilowatt power generation plant for stationary application and target electrical efficiency of over 50 per cent. Two critical technologies were investigated for high utilization stack, as high hydrogen utilization operation represents one of the most important items for the achievement of target efficiency. The first technology examined was the humidification method from cathode side, while the second was the two-block configuration, which is arranged in series in accordance with the flow of hydrogen. Using these technologies as a basis for the work, a 5 kilowatt short stack was developed, and a steady performance was obtained under high hydrogen utilization of up to 98 per cent. It is expected that by March 2003 the design of the hydrogen fueled 30 kilowatt power generation plant will be completed and assembled. 1 ref., 1 tab., 11 figs.

Hydrogen generation using the modular helium reactor

International Nuclear Information System (INIS)

Richards, M.; Shenoy, A.

2004-01-01

Process heat from a high-temperature nuclear reactor can be used to drive a set of chemical reactions, with the net result of splitting water into hydrogen and oxygen. For example, process heat at temperatures in the range 850 deg.C to 950 deg.C can drive the sulfur-iodine (SI) thermochemical process to produce hydrogen with high efficiency. Electricity can also be used to split water, using conventional, low-temperature electrolysis. An example of a hybrid process is high-temperature electrolysis (HTE), in which process heat is used to generate steam, which is then supplied to an electrolyser to generate hydrogen. In this paper we investigate the coupling of the Modular Helium Reactor (MHR) to the SI process and HTE. These concepts are referred to as the H2-MHR. Optimization of the MHR core design to produce higher coolant outlet temperatures is also discussed. The use of fixed orifices to control the flow distribution is a promising design solution for increasing the coolant outlet temperature without increasing peak fuel temperatures significantly

Zircaloy-oxidation and hydrogen-generation rates in degraded-core accident situations

International Nuclear Information System (INIS)

Chung, H.M.; Thomas, G.R.

1983-02-01

Oxidation of Zircaloy cladding is the primary source of hydrogen generated during a degraded-core accident. In this paper, reported Zircaloy oxidation rates, either measured at 1500 to 1850 0 C or extrapolated from the low-temperature data obtained at 0 C, are critically reviewed with respect to their applicability to a degraded-core accident situation in which the high-temperature fuel cladding is likely to be exposed to and oxidized in mixtures of hydrogen and depleted steam, rather than in an unlimited flux of pure steam. New results of Zircaloy oxidation measurements in various mixtures of hydrogen and steam are reported for >1500 0 C. The results show significantly smaller oxidation and, hence, hydrogen-generation rates in the mixture, compared with those obtained in pure steam. It is also shown that a significant fraction of hydrogen, generated as a result of Zircaloy oxidation, is dissolved in the cladding material itself, which prevents that portion of hydrogen from reaching the containment building space. Implications of these findings are discussed in relation to a more realistic method of quantifying the hydrogen source term for a degraded-core accident analysis

Electrokinetic Hydrogen Generation from Liquid WaterMicrojets

Energy Technology Data Exchange (ETDEWEB)

Duffin, Andrew M.; Saykally, Richard J.

2007-05-31

We describe a method for generating molecular hydrogen directly from the charge separation effected via rapid flow of liquid water through a metal orifice, wherein the input energy is the hydrostatic pressure times the volume flow rate. Both electrokinetic currents and hydrogen production rates are shown to follow simple equations derived from the overlap of the fluid velocity gradient and the anisotropic charge distribution resulting from selective adsorption of hydroxide ions to the nozzle surface. Pressure-driven fluid flow shears away the charge balancing hydronium ions from the diffuse double layer and carries them out of the aperture. Downstream neutralization of the excess protons at a grounded target electrode produces gaseous hydrogen molecules. The hydrogen production efficiency is currently very low (ca. 10-6) for a single cylindrical jet, but can be improved with design changes.

Fiscal 1998 research report on International Clean Energy Network using Hydrogen Conversion (WE-NET). Subtask 3. Conceptual design of the whole system; 1998 nendo suiso riyo kokusai clean energy system gijutsu (WE-NET) sub task 3. Zentai system gainen sekkei

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

This report summarizes the fiscal 1998 result on the conceptual design of the full-scale whole system from hydrogen production to end use. In elaboration of the conceptual design of a liquid hydrogen transport and storage system, a hydrogen combustion turbine generation facility was divided into a cryogenic oxygen production facility and a hydrogen combustion turbine generation facility, and their facility costs, annual expense ratios and scale factors were set separately for trial calculation of generation costs. In study on the profitability of alternative hydrogen production systems and the hydrogen combustion turbine generation system, the cost of the combination of hydrogen production by coal gasification or natural gas modification and the generation system was calculated. In addition, this cost was compared with the costs of liquid hydrogen, methanol or ammonia system. In study on the profitability of a distributed use system of hydrogen, a hydrogen diesel system, fuel cell system and fuel supply system for vehicles were studied roughly. (NEDO)

Investigation of thermolytic hydrogen generation rate of tank farm simulated and actual waste

Energy Technology Data Exchange (ETDEWEB)

Martino, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Newell, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Woodham, W. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Pareizs, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Edwards, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Howe, A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2017-11-15

To support resolution of Potential Inadequacies in the Safety Analysis for the Savannah River Site (SRS) Tank Farm, Savannah River National Laboratory conducted research to determine the thermolytic hydrogen generation rate (HGR) with simulated and actual waste. Gas chromatography methods were developed and used with air-purged flow systems to quantify hydrogen generation from heated simulated and actual waste at rates applicable to the Tank Farm Documented Safety Analysis (DSA). Initial simulant tests with a simple salt solution plus sodium glycolate demonstrated the behavior of the test apparatus by replicating known HGR kinetics. Additional simulant tests with the simple salt solution excluding organics apart from contaminants provided measurement of the detection and quantification limits for the apparatus with respect to hydrogen generation. Testing included a measurement of HGR on actual SRS tank waste from Tank 38. A final series of measurements examined HGR for a simulant with the most common SRS Tank Farm organics at temperatures up to 140 °C. The following conclusions result from this testing.

Configuration and technology implications of potential nuclear hydrogen system applications.

Energy Technology Data Exchange (ETDEWEB)

Conzelmann, G.; Petri, M.; Forsberg, C.; Yildiz, B.; ORNL

2005-11-05

Nuclear technologies have important distinctions and potential advantages for large-scale generation of hydrogen for U.S. energy services. Nuclear hydrogen requires no imported fossil fuels, results in lower greenhouse-gas emissions and other pollutants, lends itself to large-scale production, and is sustainable. The technical uncertainties in nuclear hydrogen processes and the reactor technologies needed to enable these processes, as well waste, proliferation, and economic issues must be successfully addressed before nuclear energy can be a major contributor to the nation's energy future. In order to address technical issues in the time frame needed to provide optimized hydrogen production choices, the Nuclear Hydrogen Initiative (NHI) must examine a wide range of new technologies, make the best use of research funding, and make early decisions on which technology options to pursue. For these reasons, it is important that system integration studies be performed to help guide the decisions made in the NHI. In framing the scope of system integration analyses, there is a hierarchy of questions that should be addressed: What hydrogen markets will exist and what are their characteristics? Which markets are most consistent with nuclear hydrogen? What nuclear power and production process configurations are optimal? What requirements are placed on the nuclear hydrogen system? The intent of the NHI system studies is to gain a better understanding of nuclear power's potential role in a hydrogen economy and what hydrogen production technologies show the most promise. This work couples with system studies sponsored by DOE-EE and other agencies that provide a basis for evaluating and selecting future hydrogen production technologies. This assessment includes identifying commercial hydrogen applications and their requirements, comparing the characteristics of nuclear hydrogen systems to those market requirements, evaluating nuclear hydrogen configuration options

Understanding oscillatory phenomena in molecular hydrogen generation via sodium borohydride hydrolysis.

Science.gov (United States)

Budroni, M A; Biosa, E; Garroni, S; Mulas, G R C; Marchettini, N; Culeddu, N; Rustici, M

2013-11-14

The hydrolysis of borohydride salts represents one of the most promising processes for the generation of high purity molecular hydrogen under mild conditions. In this work we show that the sodium borohydride hydrolysis exhibits a fingerprinting periodic oscillatory transient in the hydrogen flow over a wide range of experimental conditions. We disproved the possibility that flow oscillations are driven by supersaturation phenomena of gaseous bubbles in the reactive mixture or by a nonlinear thermal feedback according to a thermokinetic model. Our experimental results indicate that the NaBH4 hydrolysis is a spontaneous inorganic oscillator, in which the hydrogen flow oscillations are coupled to an "oscillophor" in the reactive solution. The discovery of this original oscillator paves the way for a new class of chemical oscillators, with fundamental implications not only for testing the general theory on oscillations, but also with a view to chemical control of borohydride systems used as a source of hydrogen based green fuel.

Electro-catalytic conversion of ethanol in solid electrolyte cells for distributed hydrogen generation

International Nuclear Information System (INIS)

Ju, HyungKuk; Giddey, Sarbjit; Badwal, Sukhvinder P.S.; Mulder, Roger J.

2016-01-01

Highlights: • Ethanol assisted water electrolysis reduces electric energy input by more than 50%. • Partial oxidation of ethanol leads to formation of undesired chemicals. • Degradation occurs due to formation of by-products and poisoning of catalyst. • Better catalyst has the potential to increase ethanol to H_2 conversion efficiency. • A plausible ethanol electro-oxidation mechanism has been proposed - Abstract: The global interest in hydrogen/fuel cell systems for distributed power generation and transport applications is rapidly increasing. Many automotive companies are now bringing their pre-commercial fuel cell vehicles in the market, which will need extensive hydrogen generation, distribution and storage infrastructure for fueling of these vehicles. Electrolytic water splitting coupled to renewable sources offers clean on-site hydrogen generation option. However, the process is energy intensive requiring electric energy >4.2 kWh for the electrolysis stack and >6 kWh for the complete system per m"3 of hydrogen produced. This paper investigates using ethanol as a renewable fuel to assist with water electrolysis process to substantially reduce the energy input. A zero-gap cell consisting of polymer electrolyte membrane electrolytic cells with Pt/C and PtSn/C as anode catalysts were employed. Current densities up to 200 mA cm"−"2 at 70 °C were achieved at less than 0.75 V corresponding to an energy consumption of about 1.62 kWh m"−"3 compared with >4.2 kWh m"−"3 required for conventional water electrolysis. Thus, this approach for hydrogen generation has the potential to substantially reduce the electric energy input to less than 40% with the remaining energy provided by ethanol. However, due to performance degradation over time, the energy consumption increased and partial oxidation of ethanol led to lower conversion efficiency. A plausible ethanol electro-oxidation mechanism has been proposed based on the Faradaic conversion of ethanol and

Compact hydrogen production systems for solid polymer fuel cells

Science.gov (United States)

Ledjeff-Hey, K.; Formanski, V.; Kalk, Th.; Roes, J.

Generally there are several ways to produce hydrogen gas from carbonaceous fuels like natural gas, oil or alcohols. Most of these processes are designed for large-scale industrial production and are not suitable for a compact hydrogen production system (CHYPS) in the power range of 1 kW. In order to supply solid polymer fuel cells (SPFC) with hydrogen, a compact fuel processor is required for mobile applications. The produced hydrogen-rich gas has to have a low level of harmful impurities; in particular the carbon monoxide content has to be lower than 20 ppmv. Integrating the reaction step, the gas purification and the heat supply leads to small-scale hydrogen production systems. The steam reforming of methanol is feasible at copper catalysts in a low temperature range of 200-350°C. The combination of a small-scale methanol reformer and a metal membrane as purification step forms a compact system producing high-purity hydrogen. The generation of a SPFC hydrogen fuel gas can also be performed by thermal or catalytic cracking of liquid hydrocarbons such as propane. At a temperature of 900°C the decomposition of propane into carbon and hydrogen takes place. A fuel processor based on this simple concept produces a gas stream with a hydrogen content of more than 90 vol.% and without CO and CO2.

Towards sustainable energy systems: The related role of hydrogen

International Nuclear Information System (INIS)

Hennicke, Peter; Fischedick, Manfred

2006-01-01

The role of hydrogen in long run sustainable energy scenarios for the world and for the case of Germany is analysed, based on key criteria for sustainable energy systems. The possible range of hydrogen within long-term energy scenarios is broad and uncertain depending on assumptions on used primary energy, technology mix, rate of energy efficiency increase and costs degression ('learning effects'). In any case, sustainable energy strategies must give energy efficiency highest priority combined with an accelerated market introduction of renewables ('integrated strategy'). Under these conditions hydrogen will play a major role not before 2030 using natural gas as a bridge to renewable hydrogen. Against the background of an ambitious CO 2 -reduction goal which is under discussion in Germany the potentials for efficiency increase, the necessary structural change of the power plant system (corresponding to the decision to phase out nuclear energy, the transformation of the transportation sector and the market implementation order of renewable energies ('following efficiency guidelines first for electricity generation purposes, than for heat generation and than for the transportation sector')) are analysed based on latest sustainable energy scenarios

Hydrogen generation by nuclear power for sustainable development in the 21-st century

International Nuclear Information System (INIS)

Bilegan, Iosif Constantin; Pall, Stefan

2002-01-01

Hydrogen is the main non-polluting fuel. It is produced by natural gas steam reforming, water electrolysis and thermonuclear processes. Currently, 4% of the hydrogen world production is obtained by water electrolysis. The use of nuclear power for hydrogen production avoids the generation of greenhouse gases and the dependence of primary external energy sources. The US is currently developing a modular reactor for hydrogen production and water desalination, STAR - H 2 (Secure Transportable Autonomous Reactor for Hydrogen production) with fast neutrons, lead cooling and passive safety systems operating at a temperature of 780 deg C. Also, a Russian reactor of the same type is operated at 540 deg C. China and India joint industrial countries like France, Japan, Russia and US in recognizing that any strategies aiming at a future with clean energy implies the nuclear energy

Assessment study of devices from the generation of electricity from stored hydrogen

International Nuclear Information System (INIS)

Ackerman, J.P.; Barghusen, J.J.; Link, L.E.

1975-12-01

A study was performed to evaluate alternative methods for the generation of electricity from stored hydrogen. The generation systems considered were low-temperature and high-temperature fuel cells, gas turbines and steam turbines. These systems were evaluated in terms of present-day technology and future (1995) technology. Of primary interest were the costs and efficiencies of the devices, the versatility of the devices toward various types of gaseous feeds, and the likelihood of commercial development. On the basis of these evaluations, recommendations were made describing the areas of technology which should be developed

Steam generators of Phenix: Measurement of the hydrogen concentration in sodium for detecting water leaks in the steam generator tubes; Generateurs de vapeur de Phenix-mesure de la concentration d'hydrogene du sodium pour la surveillance de l'etancheite des tubes d'eau-vapeur

Energy Technology Data Exchange (ETDEWEB)

Cambillard, E; Lacroix, A; Langlois, J; Viala, J

1975-07-01

The Phenix secondary circuits are provided with measurement systems of hydrogen concentration in sodium, that allow for the detection of possible water leaks in steam generators and the location of a faulty module. A measurement device consists of : a detector with nickel membranes of 0, 3 mm wall thickness, an ion pump with a 200 l/s flow rate, a quadrupole mass spectrometer and a calibrated hydrogen leak. The temperature correction is made automatically. The main tests carried out on the leak detection systems are reported. Since the first system operation (October 24, 1973), the measurements allowed us to obtain the hydrogen diffusion rates through the steam generator tube walls. (author)

A method for generating hydrogen from water

International Nuclear Information System (INIS)

Godin, Paul; Mascarello, Jean; Millet, Jacques.

1974-01-01

Description is given of a method and an installation for generating hydrogen from water, through an endothermic cycle of several successive chemical reactions involving intermediate substances regenerated during said cycle, said reactions occuring at different temperatures. The reaction which takes place at the highest temperature is carried out electrochemically. This can be applied to power-generating units comprising a nuclear reactor [fr

Mitigation of Hydrogen Gas Generation from the Reaction of Water with Uranium Metal in K Basins Sludge

International Nuclear Information System (INIS)

Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

2010-01-01

Means to decrease the rate of hydrogen gas generation from the chemical reaction of uranium metal with water were identified by surveying the technical literature. The underlying chemistry and potential side reactions were explored by conducting 61 principal experiments. Several methods achieved significant hydrogen gas generation rate mitigation. Gas-generating side reactions from interactions of organics or sludge constituents with mitigating agents were observed. Further testing is recommended to develop deeper knowledge of the underlying chemistry and to advance the technology aturation level. Uranium metal reacts with water in K Basin sludge to form uranium hydride (UH3), uranium dioxide or uraninite (UO2), and diatomic hydrogen (H2). Mechanistic studies show that hydrogen radicals (H·) and UH3 serve as intermediates in the reaction of uranium metal with water to produce H2 and UO2. Because H2 is flammable, its release into the gas phase above K Basin sludge during sludge storage, processing, immobilization, shipment, and disposal is a concern to the safety of those operations. Findings from the technical literature and from experimental investigations with simple chemical systems (including uranium metal in water), in the presence of individual sludge simulant components, with complete sludge simulants, and with actual K Basin sludge are presented in this report. Based on the literature review and intermediate lab test results, sodium nitrate, sodium nitrite, Nochar Acid Bond N960, disodium hydrogen phosphate, and hexavalent uranium [U(VI)] were tested for their effects in decreasing the rate of hydrogen generation from the reaction of uranium metal with water. Nitrate and nitrite each were effective, decreasing hydrogen generation rates in actual sludge by factors of about 100 to 1000 when used at 0.5 molar (M) concentrations. Higher attenuation factors were achieved in tests with aqueous solutions alone. Nochar N960, a water sorbent, decreased hydrogen

Mitigation of Hydrogen Gas Generation from the Reaction of Water with Uranium Metal in K Basins Sludge

Energy Technology Data Exchange (ETDEWEB)

Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

2010-01-29

Means to decrease the rate of hydrogen gas generation from the chemical reaction of uranium metal with water were identified by surveying the technical literature. The underlying chemistry and potential side reactions were explored by conducting 61 principal experiments. Several methods achieved significant hydrogen gas generation rate mitigation. Gas-generating side reactions from interactions of organics or sludge constituents with mitigating agents were observed. Further testing is recommended to develop deeper knowledge of the underlying chemistry and to advance the technology aturation level. Uranium metal reacts with water in K Basin sludge to form uranium hydride (UH3), uranium dioxide or uraninite (UO2), and diatomic hydrogen (H2). Mechanistic studies show that hydrogen radicals (H·) and UH3 serve as intermediates in the reaction of uranium metal with water to produce H2 and UO2. Because H2 is flammable, its release into the gas phase above K Basin sludge during sludge storage, processing, immobilization, shipment, and disposal is a concern to the safety of those operations. Findings from the technical literature and from experimental investigations with simple chemical systems (including uranium metal in water), in the presence of individual sludge simulant components, with complete sludge simulants, and with actual K Basin sludge are presented in this report. Based on the literature review and intermediate lab test results, sodium nitrate, sodium nitrite, Nochar Acid Bond N960, disodium hydrogen phosphate, and hexavalent uranium [U(VI)] were tested for their effects in decreasing the rate of hydrogen generation from the reaction of uranium metal with water. Nitrate and nitrite each were effective, decreasing hydrogen generation rates in actual sludge by factors of about 100 to 1000 when used at 0.5 molar (M) concentrations. Higher attenuation factors were achieved in tests with aqueous solutions alone. Nochar N960, a water sorbent, decreased hydrogen

Molecular cobalt pentapyridine catalysts for generating hydrogen from water

Science.gov (United States)

Long, Jeffrey R; Chang, Christopher J; Sun, Yujie

2013-11-05

A composition of matter suitable for the generation of hydrogen from water is described, the positively charged cation of the composition including the moiety of the general formula. [(PY5Me.sub.2)CoL].sup.2+, where L can be H.sub.2O, OH.sup.-, a halide, alcohol, ether, amine, and the like. In embodiments of the invention, water, such as tap water or sea water can be subject to low electric potentials, with the result being, among other things, the generation of hydrogen.

A Hydrogen Ignition Mechanism for Explosions in Nuclear Facility Piping Systems

Energy Technology Data Exchange (ETDEWEB)

Leishear, Robert A.

2013-09-18

Hydrogen explosions may occur simultaneously with water hammer accidents in nuclear facilities, and a theoretical mechanism to relate water hammer to hydrogen deflagrations and explosions is presented herein. Hydrogen and oxygen generation due to the radiolysis of water is a recognized hazard in pipe systems used in the nuclear industry, where the accumulation of hydrogen and oxygen at high points in the pipe system is expected, and explosive conditions may occur. Pipe ruptures in nuclear reactor cooling systems were attributed to hydrogen explosions inside pipelines, i.e., Hamaoka, Nuclear Power Station in Japan, and Brunsbuettel in Germany. Prior to these accidents, an ignition source for hydrogen was not clearly demonstrated, but these accidents demonstrated that a mechanism was, in fact, available to initiate combustion and explosion. A new theory to identify an ignition source and explosion cause is presented here, and further research is recommended to fully understand this explosion mechanism.

Hydrogen energy systems studies

Energy Technology Data Exchange (ETDEWEB)

Ogden, J.M.; Steinbugler, M.; Dennis, E. [Princeton Univ., NJ (United States)] [and others

1995-09-01

For several years, researchers at Princeton University`s Center for Energy and Environmental Studies have carried out technical and economic assessments of hydrogen energy systems. Initially, we focussed on the long term potential of renewable hydrogen. More recently we have explored how a transition to renewable hydrogen might begin. The goal of our current work is to identify promising strategies leading from near term hydrogen markets and technologies toward eventual large scale use of renewable hydrogen as an energy carrier. Our approach has been to assess the entire hydrogen energy system from production through end-use considering technical performance, economics, infrastructure and environmental issues. This work is part of the systems analysis activity of the DOE Hydrogen Program. In this paper we first summarize the results of three tasks which were completed during the past year under NREL Contract No. XR-11265-2: in Task 1, we carried out assessments of near term options for supplying hydrogen transportation fuel from natural gas; in Task 2, we assessed the feasibility of using the existing natural gas system with hydrogen and hydrogen blends; and in Task 3, we carried out a study of PEM fuel cells for residential cogeneration applications, a market which might have less stringent cost requirements than transportation. We then give preliminary results for two other tasks which are ongoing under DOE Contract No. DE-FG04-94AL85803: In Task 1 we are assessing the technical options for low cost small scale production of hydrogen from natural gas, considering (a) steam reforming, (b) partial oxidation and (c) autothermal reforming, and in Task 2 we are assessing potential markets for hydrogen in Southern California.

Possibility of hydrogen supply by shared residential fuel cell systems for fuel cell vehicles

Directory of Open Access Journals (Sweden)

Ono Yusuke

2017-01-01

Full Text Available Residential polymer electrolyte fuel cells cogeneration systems (residential PEFC systems produce hydrogen from city gas by internal gas-reformer, and generate electricity, the hot water at the same time. From the viewpoint of the operation, it is known that residential PEFC systems do not continuously work but stop for long time, because the systems generate enough hot water for short operation time. In other words, currently residential PEFC systems are dominated by the amount of hot water demand. This study focuses on the idle time of residential PEFC systems. Since their gas-reformers are free, the systems have potential to produce hydrogen during the partial load operations. The authors expect that residential PEFC systems can take a role to supply hydrogen for fuel cell vehicles (FCVs before hydrogen fueling stations are distributed enough. From this perspective, the objective of this study is to evaluate the hydrogen production potential of residential PEFC systems. A residential PEFC system was modeled by the mixed integer linear programming to optimize the operation including hydrogen supply for FCV. The objective function represents annual system cost to be minimized with the constraints of energy balance. It should be noted that the partial load characteristics of the gas-reformer and the fuel cell stack are taken into account to derive the optimal operation. The model was employed to estimate the possible amount of hydrogen supply by a residential PEFC system. The results indicated that the system could satisfy at least hydrogen demand for transportation of 8000 km which is as far as the average annual mileage of a passenger car in Japan. Furthermore, hydrogen production by sharing a residential PEFC system with two households is more effective to reduce primary energy consumption with hydrogen supply for FCV than the case of introducing PEFC in each household.

Enhanced Solar-to-Hydrogen Generation with Broadband Epsilon-Near-Zero Nanostructured Photocatalysts

KAUST Repository

Tian, Yi

2017-05-08

The direct conversion of solar energy into fuels or feedstock is an attractive approach to address increasing demand of renewable energy sources. Photocatalytic systems relying on the direct photoexcitation of metals have been explored to this end, a strategy that exploits the decay of plasmonic resonances into hot carriers. An efficient hot carrier generation and collection requires, ideally, their generation to be enclosed within few tens of nanometers at the metal interface, but it is challenging to achieve this across the broadband solar spectrum. Here the authors demonstrate a new photocatalyst for hydrogen evolution based on metal epsilon-near-zero metamaterials. The authors have designed these to achieve broadband strong light confinement at the metal interface across the entire solar spectrum. Using electron energy loss spectroscopy, the authors prove that hot carriers are generated in a broadband fashion within 10 nm in this system. The resulting photocatalyst achieves a hydrogen production rate of 9.5 µmol h-1  cm-2 that exceeds, by a factor of 3.2, that of the best previously reported plasmonic-based photocatalysts for the dissociation of H2 with 50 h stable operation.

Micro hydrogen for portable power : generating opportunities for hydrogen and fuel cells

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-07-01

A new fuel cell technology for portable applications was reviewed. Success for the fuel cell industry will be achieved primarily by supplanting lithium-ion batteries, and fuel cells for portable applications have clear advantages to batteries in addition to their known environmental benefits. Micro hydrogen {sup TM} is the integrated combination of hydrogen fuel cell, hydrogen storage and delivery, fluidic interconnects and power conditioning electronics required for creating high energy density portable power sources. The small size, low heat production, environmental sustainability and refueling flexibility of the systems provides enormous economic opportunities for the use of micro hydrogen in cell phone technology, personal digital assistants and other electronic gadgets. Details of a trial to test and evaluate micro hydrogen fuel cell powered bike lights were presented. Further programs are planned for external demonstrations of high-beam search and rescue lighting, flashlights for security personnel and portable hydrogen power sources that will be used by multiple organizations throughout British Columbia. It was concluded that fuel cell technology must match the lithium-ion battery's performance by providing fast recharge, high energy density, and adaptability. Issues concerning refueling and portable and disposable cartridges for micro hydrogen systems were also discussed. 8 figs.

Hydrogen generation in SRAT with nitric acid and late washing flowsheets

International Nuclear Information System (INIS)

Hsu, C.W.

1992-01-01

Melter feed preparation processes, incorporating a final wash of the precipitate slurry feed to Defense Waste Processing Facility (DWPF) and a partial substitution of the SRAT formic acid requirement with nitric acid, should not produce peak hydrogen generation rates during Cold Chemical Runs (CCR's) and radioactive operation greater than their current, respective hydrogen design bases of 0.024 lb/hr and 1.5 lb/hr. A single SRAT bench-scale process simulation for CCR-s produced a DWPF equivalent peak hydrogen generation rate of 0.004 lb/hr. During radioactive operation, the peak hydrogen generation rate will be dependent on the extent DWPF deviates from the nominal precipitate hydrolysis and melter feed preparation process operating parameters. Two actual radioactive sludges were treated according to the new flowsheets. The peak hydrogen evolution rates were equivalent to 0.038 and 0.20 lb/hr (DWPF scale) respectively. Compared to the formic acid -- HAN hydrolysis flowsheets, these peak rates were reduced by a factor of 2.5 and 3.4 for Tank 15 and Tank 11 sludges, respectively

Relations between oxygen and hydrogen generated by radiolysis in the systems of a CANDU 600

International Nuclear Information System (INIS)

Romano, Christian; Chocron, Mauricio; Urrutia, Guillermo

1999-01-01

The water that constitutes the coolant of the primary heat transport system, the moderator and the liquid control zones, decomposed under radiation producing as stable products oxygen, hydrogen and hydrogen peroxide throughout a complex mechanisms of radiolysis that involves ions and free radicals. These compound formed in different proportions alters the chemical control established for each system which purpose is to minimize the corrosion of the structural materials. In the present paper have been presented results of the modelling of the mentioned processes and it has been found that in the absence of a vapor phase, a relatively low concentration of hydrogen added to the water would be sufficient to control the formation of oxygen and hydrogen peroxide. The last species however, would remain in relatively high values inside a coolant fuel channel in the reactor core. (author)

The Palm Desert renewable [hydrogen] transportation system

Energy Technology Data Exchange (ETDEWEB)

Chamberlin, C.E.; Lehman, P. [Humboldt State Univ., Arcata, CA (United States). Schatz Energy Research Center

1998-08-01

This paper describes the Schatz Energy Research Center (SERC) progress on the Palm Desert Renewable Hydrogen Transportation System Project for the period June 1997 through May 1998. The project began in March 1996. The goal of the Palm Desert Project is to develop a clean and sustainable transportation system for a community. The project demonstrates the practical utility of hydrogen as a transportation fuel and the proton exchange membrane (PEM) fuel cell as a vehicle power system. The project includes designing and building 4 fuel cell powered vehicles, a solar hydrogen generating and refueling station, and a fuel cell vehicle diagnostic center. Over this last year, SERC has built a fuel cell powered neighborhood electric vehicle and delivered it to the City of Palm Desert. The design of the hydrogen refueling station is near completion and it is anticipated that construction will be complete in the fall of 1998. The vehicles are currently being refueled at a temporary refueling station. The diagnostic center is being designed and maintenance procedures as well as computer diagnostic programs for the fuel cell vehicles are being developed. City employees are driving the vehicles daily and monitoring data are being collected. The drivers are pleased with the performance of the vehicles.

Photocatalysis in Generation of Hydrogen from Water

KAUST Repository

Takanabe, Kazuhiro

2015-04-18

Solar energy can be converted by utilizing the thermal or photoelectric effects of photons. Concentrated solar power systems utilize thermal energy from the sun by either making steam and then generating power or shifting the chemical equilibrium of a reaction (e.g., water splitting or CO2 reduction) that occurs at extremely high temperatures. The photocatalytic system contains powder photocatalysts. Each photocatalyst particle should collect sufficient photons from the solar flux to cause the required multielectron reactions to occur. The band gap and band edge positions of semiconductors are the most critical parameters for assessing the suitability of photocatalysts for overall water splitting. The most important requirement when selecting photocatalyst materials is the band positions relative to hydrogen and oxygen evolution potentials. For most photocatalysts, surface modification by cocatalysts was found to be essential to achieve overall water splitting.

Hanford Waste Vitrification Plant hydrogen generation

International Nuclear Information System (INIS)

King, R.B.; King, A.D. Jr.; Bhattacharyya, N.K.

1996-02-01

The most promising method for the disposal of highly radioactive nuclear wastes is a vitrification process in which the wastes are incorporated into borosilicate glass logs, the logs are sealed into welded stainless steel canisters, and the canisters are buried in suitably protected burial sites for disposal. The purpose of the research supported by the Hanford Waste Vitrification Plant (HWVP) project of the Department of Energy through Battelle Pacific Northwest Laboratory (PNL) and summarized in this report was to gain a basic understanding of the hydrogen generation process and to predict the rate and amount of hydrogen generation during the treatment of HWVP feed simulants with formic acid. The objectives of the study were to determine the key feed components and process variables which enhance or inhibit the.production of hydrogen. Information on the kinetics and stoichiometry of relevant formic acid reactions were sought to provide a basis for viable mechanistic proposals. The chemical reactions were characterized through the production and consumption of the key gaseous products such as H 2 . CO 2 , N 2 0, NO, and NH 3 . For this mason this research program relied heavily on analyses of the gases produced and consumed during reactions of the HWVP feed simulants with formic acid under various conditions. Such analyses, used gas chromatographic equipment and expertise at the University of Georgia for the separation and determination of H 2 , CO, CO 2 , N 2 , N 2 O and NO

Design and Control of Integrated Systems for Hydrogen Production and Power Generation

Science.gov (United States)

Georgis, Dimitrios

Growing concerns on CO2 emissions have led to the development of highly efficient power plants. Options for increased energy efficiencies include alternative energy conversion pathways, energy integration and process intensification. Solid oxide fuel cells (SOFC) constitute a promising alternative for power generation since they convert the chemical energy electrochemically directly to electricity. Their high operating temperature shows potential for energy integration with energy intensive units (e.g. steam reforming reactors). Although energy integration is an essential tool for increased efficiencies, it leads to highly complex process schemes with rich dynamic behavior, which are challenging to control. Furthermore, the use of process intensification for increased energy efficiency imposes an additional control challenge. This dissertation identifies and proposes solutions on design, operational and control challenges of integrated systems for hydrogen production and power generation. Initially, a study on energy integrated SOFC systems is presented. Design alternatives are identified, control strategies are proposed for each alternative and their validity is evaluated under different operational scenarios. The operational range of the proposed control strategies is also analyzed. Next, thermal management of water gas shift membrane reactors, which are a typical application of process intensification, is considered. Design and operational objectives are identified and a control strategy is proposed employing advanced control algorithms. The performance of the proposed control strategy is evaluated and compared with classical control strategies. Finally SOFC systems for combined heat and power applications are considered. Multiple recycle loops are placed to increase design flexibility. Different operational objectives are identified and a nonlinear optimization problem is formulated. Optimal designs are obtained and their features are discussed and compared

Portable Fuel Cell Battery Charger with Integrated Hydrogen Generator

Energy Technology Data Exchange (ETDEWEB)

Bossel, Ulf G. [CH-5452 Oberrohrdorf (Switzerland)

1999-10-01

A fully self-sufficient portable fuel cell battery charger has been designed, built, operated and is now prepared for commercialisation. The lightweight device is equipped with 24 circular polymer electrolyte cells of an innovative design. Each cell is a complete unit and can be tested prior to stacking. Hydrogen is admitted to the anode chamber from the centre of the cell. Air can reach the cathode by diffusion through a porous metal foam layer placed between cathode and separator plate. Soft seals surround the centre hole of the cells to separate hydrogen from air. Water vapour generated by the electrochemical conversion is released into the atmosphere via the porous metal foam on the cathode. All hydrogen fed to the dead-ended anode chamber is converted to electric power. The device is equipped with a chemical hydrogen generator. The fuel gas is formed by adding small amounts of water to a particular chemical compound which is contained in disposable cartridges. With one such cartridge enough hydrogen can be generated to operate CD-players, radios, recorders or portable computers for some hours, depending on the current drawn by the electronic device. The handy portable battery charger delivers about 10 W at 12 V DC. It is designed to be used in remote areas as autonomous power source for charging batteries used in radios, CD players, cellular telephones, radio transmitters, flash lights or model air planes. The power can also be used directly to provide light, sound or motion. Patents have been filed and partners are sought for commercialisation. (author) 4 figs.

Modeling the reaction kinetics of a hydrogen generator onboard a fuel cell -- Electric hybrid motorcycle

Science.gov (United States)

Ganesh, Karthik

Owing to the perceived decline of the fossil fuel reserves in the world and environmental issues like pollution, conventional fuels may be replaced by cleaner alternative fuels. The potential of hydrogen as a fuel in vehicular applications is being explored. Hydrogen as an energy carrier potentially finds applications in internal combustion engines and fuel cells because it is considered a clean fuel and has high specific energy. However, at 6 to 8 per kilogram, not only is hydrogen produced from conventional methods like steam reforming expensive, but also there are storage and handling issues, safety concerns and lack of hydrogen refilling stations across the country. The purpose of this research is to suggest a cheap and viable system that generates hydrogen on demand through a chemical reaction between an aluminum-water slurry and an aqueous sodium hydroxide solution to power a 2 kW fuel cell on a fuel cell hybrid motorcycle. This reaction is essentially an aluminum-water reaction where sodium hydroxide acts as a reaction promoter or catalyst. The Horizon 2000 fuel cell used for this purpose has a maximum hydrogen intake rate of 28 lpm. The study focuses on studying the exothermic reaction between the reactants and proposes a rate law that best describes the rate of generation of hydrogen in connection to the surface area of aluminum available for the certain reaction and the concentration of the sodium hydroxide solution. Further, the proposed rate law is used in the simulation model of the chemical reactor onboard the hybrid motorcycle to determine the hydrogen flow rate to the fuel cell with time. Based on the simulated rate of production of hydrogen from the chemical system, its feasibility of use on different drive cycles is analyzed. The rate of production of hydrogen with a higher concentration of sodium hydroxide and smaller aluminum powder size was found to enable the installation of the chemical reactor on urban cycles with frequent stops and starts

Evaluation tool for selection and optimisation of hydrogen demonstration projects. Application to a decentralized renewable hydrogen system

International Nuclear Information System (INIS)

Bracht, M.; De Groot, A.; Gregoire Padro, C.E.; Schucan, T.H.; Skolnik, E.

1998-06-01

As part of the International Energy Agency Hydrogen Implementing Agreement, an evaluation tool to assist in the design, operation and optimisation of hydrogen demonstration facilities is under development. Using commercially available flowsheet simulation software (ASPEN- Plus) as the integrating platform, this tool is designed to provide system developers with a comprehensive data base or library of component models and an integrating platform through which these models may be linked. By combining several energy system components a conceptual design of a integrated hydrogen energy system can be made. As a part of the tool and connected to the library are design guidelines which can help finding the optimal configuration in the design process. The component categories considered include: production, storage, transport, distribution and end use. Many component models have already been included in the initial test platform. The use of the tool will be illustrated by presenting the results of a specific sample system that has been designed and assessed with use of the tool. The system considered is a decentralized renewable hydrogen system in which the hydrogen is produced by biomass gasification or pyrolysis, the produced hydrogen is transported through a pipeline or with a tank truck. The storage options that are considered are liquid hydrogen and compressed gas. The hydrogen is dispensed through a refueling station. Several options for integration are conceivable; i.e. storage of the hydrogen can take place centrally or district heat of a gasification unit can be used to generate electricity for liquefaction, etc. With use of the tool several configurations with different components and various integration options have been examined. Both the results of the modeling effort and an assessment of the evaluation tool will be presented. 5 refs

Hydrogen detection systems leak response codes

International Nuclear Information System (INIS)

Desmas, T.; Kong, N.; Maupre, J.P.; Schindler, P.; Blanc, D.

1990-01-01

A loss in tightness of a water tube inside a Steam Generator Unit of a Fast Reactor is usually monitored by hydrogen detection systems. Such systems have demonstrated in the past their ability to detect a leak in a SGU. However, the increase in size of the SGU or the choice of ferritic material entails improvement of these systems in order to avoid secondary leak or to limit damages to the tube bundle. The R and D undertaken in France on this subject is presented. (author). 11 refs, 10 figs

Photoelectrochemical based direct conversion systems for hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Kocha, S.; Peterson, M.; Arent, D. [National Renewable Energy Lab., Golden, CO (United States)] [and others

1996-10-01

Photon driven, direct conversion systems consist of a light absorber and a water splitting catalyst as a monolithic system; water is split directly upon illumination. This one-step process eliminates the need to generate electricity externally and subsequently feed it to an electrolyzer. These configurations require only the piping necessary for transport of hydrogen to an external storage system or gas pipeline. This work is focused on multiphoton photoelectrochemical devices for production of hydrogen directly using sunlight and water. Two types of multijunction cells, one consisting of a-Si triple junctions and the other GaInP{sub 2}/GaAs homojunctions, were studied for the photoelectrochemical decomposition of water into hydrogen and oxygen from an aqueous electrolyte solution. To catalyze the water decomposition process, the illuminated surface of the device was modified either by addition of platinum colloids or by coating with ruthenium dioxide. These colloids have been characterized by gel electrophoresis.

Sum Frequency Generation Studies of Hydrogenation Reactions on Platinum Nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Krier, James M. [Univ. of California, Berkeley, CA (United States)

2013-08-31

Sum Frequency Generation (SFG) vibrational spectroscopy is used to characterize intermediate species of hydrogenation reactions on the surface of platinum nanoparticle catalysts. In contrast to other spectroscopy techniques which operate in ultra-high vacuum or probe surface species after reaction, SFG collects information under normal conditions as the reaction is taking place. Several systems have been studied previously using SFG on single crystals, notably alkene hydrogenation on Pt(111). In this thesis, many aspects of SFG experiments on colloidal nanoparticles are explored for the first time. To address spectral interference by the capping agent (PVP), three procedures are proposed: UV cleaning, H2 induced disordering and calcination (core-shell nanoparticles). UV cleaning and calcination physically destroy organic capping while disordering reduces SFG signal through a reversible structural change by PVP.

Solar hydrogen production: renewable hydrogen production by dry fuel reforming

Science.gov (United States)

Bakos, Jamie; Miyamoto, Henry K.

2006-09-01

SHEC LABS - Solar Hydrogen Energy Corporation constructed a pilot-plant to demonstrate a Dry Fuel Reforming (DFR) system that is heated primarily by sunlight focusing-mirrors. The pilot-plant consists of: 1) a solar mirror array and solar concentrator and shutter system; and 2) two thermo-catalytic reactors to convert Methane, Carbon Dioxide, and Water into Hydrogen. Results from the pilot study show that solar Hydrogen generation is feasible and cost-competitive with traditional Hydrogen production. More than 95% of Hydrogen commercially produced today is by the Steam Methane Reformation (SMR) of natural gas, a process that liberates Carbon Dioxide to the atmosphere. The SMR process provides a net energy loss of 30 to 35% when converting from Methane to Hydrogen. Solar Hydrogen production provides a 14% net energy gain when converting Methane into Hydrogen since the energy used to drive the process is from the sun. The environmental benefits of generating Hydrogen using renewable energy include significant greenhouse gas and criteria air contaminant reductions.

Autothermal hydrogen storage and delivery systems

Science.gov (United States)

Pez, Guido Peter [Allentown, PA; Cooper, Alan Charles [Macungie, PA; Scott, Aaron Raymond [Allentown, PA

2011-08-23

Processes are provided for the storage and release of hydrogen by means of dehydrogenation of hydrogen carrier compositions where at least part of the heat of dehydrogenation is provided by a hydrogen-reversible selective oxidation of the carrier. Autothermal generation of hydrogen is achieved wherein sufficient heat is provided to sustain the at least partial endothermic dehydrogenation of the carrier at reaction temperature. The at least partially dehydrogenated and at least partially selectively oxidized liquid carrier is regenerated in a catalytic hydrogenation process where apart from an incidental employment of process heat, gaseous hydrogen is the primary source of reversibly contained hydrogen and the necessary reaction energy.

Carbon Dioxide-Free Hydrogen Production with Integrated Hydrogen Separation and Storage.

Science.gov (United States)

Dürr, Stefan; Müller, Michael; Jorschick, Holger; Helmin, Marta; Bösmann, Andreas; Palkovits, Regina; Wasserscheid, Peter

2017-01-10

An integration of CO 2 -free hydrogen generation through methane decomposition coupled with hydrogen/methane separation and chemical hydrogen storage through liquid organic hydrogen carrier (LOHC) systems is demonstrated. A potential, very interesting application is the upgrading of stranded gas, for example, gas from a remote gas field or associated gas from off-shore oil drilling. Stranded gas can be effectively converted in a catalytic process by methane decomposition into solid carbon and a hydrogen/methane mixture that can be directly fed to a hydrogenation unit to load a LOHC with hydrogen. This allows for a straight-forward separation of hydrogen from CH 4 and conversion of hydrogen to a hydrogen-rich LOHC material. Both, the hydrogen-rich LOHC material and the generated carbon on metal can easily be transported to destinations of further industrial use by established transport systems, like ships or trucks. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sodium borohydride hydrogen generator using Co–P/Ni foam catalysts for 200 W proton exchange membrane fuel cell system

International Nuclear Information System (INIS)

Oh, Taek Hyun; Gang, Byeong Gyu; Kim, Hyuntak; Kwon, Sejin

2015-01-01

The response characteristics of electroless-deposited Co–P/Ni foam catalysts for sodium borohydride hydrolysis were investigated. The effect of nickel foam geometry on the properties of the catalysts was evaluated. As the PPI (pores per inch) of the nickel foam increased, the hydrogen generation rate per gram of the deposited catalyst increased due to an increase in surface area. The response characteristics of various catalysts were compared under real operating conditions. When a thin nickel foam with high PPI was used, the response characteristics of the catalyst improved due to an increase in the amount of the deposited catalyst and surface area. Finally, a 200 W PEMFC (proton exchange membrane fuel cell) system using electroless-deposited Co–P/Ni foam (110 PPI) catalyst was investigated. The response time to reach a hydrogen generation rate sufficient for a 200 W PEMFC was 71 s, and the energy density of a 200 W fuel cell system for producing 600 Wh was 252.1 Wh/kg. A fuel cell system using Co–P/Ni foam catalysts can be widely used as a power source for mobile applications due to fast response characteristics and high energy density. - Highlights: • Response characteristics of Co–P/Ni foam catalysts are investigated. • Catalytic activity is improved with increase in PPI (pores per inch) of Ni foam. • Co–P/Ni foam (110 PPI) catalyst has improved response characteristics. • The energy density of a 200 W PEMFC system for producing 600 Wh is 252.1 Wh/kg. • Co–P/Ni foam (110 PPI) catalyst is suitable for fuel cell system.

Performance test results of mock-up test facility of HTTR hydrogen production system

International Nuclear Information System (INIS)

Ohashi, Hirofumi; Inaba, Yoshitomo; Nishihara, Tetsuo

2004-01-01

For the purpose to demonstrate effectiveness of high-temperature nuclear heat utilization, Japan Atomic Energy Research Institute has been developing a hydrogen production system and has planned to connect the hydrogen production system to High Temperature Engineering Test Reactor (HTTR). Prior to construction of a HTTR hydrogen production system, a mock-up test facility was constructed to investigate transient behavior of the hydrogen production system and to establish system controllability. The Mock-up test facility with a full-scale reaction tube is an approximately 1/30-scale model of the HTTR hydrogen production system and an electric heater is used as a heat source instead of a reactor. After its construction, a performance test of the test facility was carried out in the same pressure and temperature conditions as those of the HTTR hydrogen production system to investigate its performance such as hydrogen production ability, controllability and so on. It was confirmed that hydrogen was stably produced with a hot helium gas about 120m 3 /h, which satisfy the design value, and thermal disturbance of helium gas during the start-up could be mitigated within the design value by using a steam generator. The mock-up test of the HTTR hydrogen production system using this facility will continue until 2004. (author)

Dependable Hydrogen and Industrial Heat Generation from the Next Generation Nuclear Plant

Energy Technology Data Exchange (ETDEWEB)

Charles V. Park; Michael W. Patterson; Vincent C. Maio; Piyush Sabharwall

2009-03-01

The Department of Energy is working with industry to develop a next generation, high-temperature gas-cooled nuclear reactor (HTGR) as a part of the effort to supply the US with abundant, clean and secure energy. The Next Generation Nuclear Plant (NGNP) project, led by the Idaho National Laboratory, will demonstrate the ability of the HTGR to generate hydrogen, electricity, and high-quality process heat for a wide range of industrial applications. Substituting HTGR power for traditional fossil fuel resources reduces the cost and supply vulnerability of natural gas and oil, and reduces or eliminates greenhouse gas emissions. As authorized by the Energy Policy Act of 2005, industry leaders are developing designs for the construction of a commercial prototype producing up to 600 MWt of power by 2021. This paper describes a variety of critical applications that are appropriate for the HTGR with an emphasis placed on applications requiring a clean and reliable source of hydrogen. An overview of the NGNP project status and its significant technology development efforts are also presented.

Leak detection in steam generators with hydrogen monitors using diffusion membranes

Energy Technology Data Exchange (ETDEWEB)

Hissink, M

1975-07-01

Large water leaks in steam-generators give rise to violent chemical reactions which can only be controlled by a pressure relief system. Smaller leaks do not pose direct safety hazards but wastage of pipes surrounding the leak should be prevented. Leak detection is best carried out by monitors recording the hydrogen in sodium content. For large leaks the specification of these monitors causes no problems, contrary to those for the timely detection of small leaks. Essential parameters are sensitivity and speed of response, specificity is less important. But apart from the instrument specification, a number of factors, related to the construction and operation of the steam-generator, determine the performance of the leak detection system. A discussion of these factors is given, with a view to the design of the SNR-300. Although tile results of many theoretical studies and experimental work are available, there seems to be room for further investigations on the growths of minor leaks. Also lacking a sufficient experience concerning the level and fluctuations of the hydrogen background in the sodium. A description is given of the hydrogen monitor developed at TNO, which is based on a combination of a nickel membrane and an ion getter pump. The parameters of this instrument have been evaluated in a test rig. Operational experience with the monitor is available from the 50 MW Test Facility at Hengelo. Especially for further studies the need for a calibrated instrument has become apparent. Test are going on with a modified design of a monitor meeting this requirement. (author)

Hydrogen generator from light hydrocarbons for stationary applications

International Nuclear Information System (INIS)

Cipiti, F.; Recupero, Vincenzo; Pino, L.; Vita, A.; Lagana, M.

2006-01-01

The present article describes the activities carried out in the CNR institute, particularly the development, realization and testing of one unit of hydrogen generation to integrate with fuel-cells for residential applications [it

Optimizing investments in coupled offshore wind -electrolytic hydrogen storage systems in Denmark

Science.gov (United States)

Hou, Peng; Enevoldsen, Peter; Eichman, Joshua; Hu, Weihao; Jacobson, Mark Z.; Chen, Zhe

2017-08-01

In response to electricity markets with growing levels of wind energy production and varying electricity prices, this research examines incentives for investments in integrated renewable energy power systems. A strategy for using optimization methods for a power system consisting of wind turbines, electrolyzers, and hydrogen fuel cells is explored. This research reveals the investment potential of coupling offshore wind farms with different hydrogen systems. The benefits in terms of a return on investment are demonstrated with data from the Danish electricity markets. This research also investigates the tradeoffs between selling the hydrogen directly to customers or using it as a storage medium to re-generate electricity at a time when it is more valuable. This research finds that the most beneficial configuration is to produce hydrogen at a time that complements the wind farm and sell the hydrogen directly to end users.

Perspectives for generation companies and the emerging hydrogen economy

International Nuclear Information System (INIS)

Cowan, N.

2004-01-01

'Full text:' Canadian and global power generation supply is evolving towards inclusion of emerging types of technologies for electricity production. Although much of Canadian electricity supply will continue to be derived from traditional sources in the foreseeable future the band for capital cost competitiveness is narrowing between the once clear-cut technological winners and emerging generation technologies creating opportunity for new technologies to commercialize in the market. OPG has been active in the development and commercialization of stationary high temperature fuel cells for several years. The major activity has been a partnering initiative to engineer and implement Solid Oxide Fuel Cell (SOFC) demonstration installations. The relationship with SOFC developer Siemens-Westinghouse out of Pittsburgh has allowed OPG to maintain an ongoing involvement in the emerging fuel cell industry, while exploring the broader implications of this technology for the power industry business model. OPG is part of the 'Hydrogen Village Partnership'. The Hydrogen Village will demonstrate and deploy various hydrogen production, storage and delivery techniques as well as applications of hydrogen such as fuel cells for stationary, transportation (mobile) and portable applications. OPG maintains an active role in the demonstration of emerging technologies for a number of reasons: 1) advancing commercialization of emerging generation technologies, 2) 'hands-on' participation in the deployment of such technology in order to gather and apply market knowledge 3) Involvement in developing technology as a part of commitment to sustainable development. (author)

Hydrogen Purification and Recycling for an Integrated Oxygen Recovery System Architecture

Science.gov (United States)

Abney, Morgan B.; Greenwood, Zachary; Wall, Terry; Miller, Lee; Wheeler, Ray

2016-01-01

The United States Atmosphere Revitalization life support system on the International Space Station (ISS) performs several services for the crew including oxygen generation, trace contaminant control, carbon dioxide (CO2) removal, and oxygen recovery. Oxygen recovery is performed using a Sabatier reactor developed by Hamilton Sundstrand, wherein CO2 is reduced with hydrogen in a catalytic reactor to produce methane and water. The water product is purified in the Water Purification Assembly and recycled to the Oxygen Generation Assembly (OGA) to provide O2 to the crew. This architecture results in a theoretical maximum oxygen recovery from CO2 of approximately 54% due to the loss of reactant hydrogen in Sabatier-produced methane that is currently vented outside of ISS. Plasma Methane Pyrolysis technology (PPA), developed by Umpqua Research Company, provides the capability to further close the Atmosphere Revitalization oxygen loop by recovering hydrogen from Sabatier-produced methane. A key aspect of this technology approach is to purify the hydrogen from the PPA product stream which includes acetylene, unreacted methane and byproduct water and carbon monoxide. In 2015, four sub-scale hydrogen separation systems were delivered to NASA for evaluation. These included two electrolysis single-cell hydrogen purification cell stacks developed by Sustainable Innovations, LLC, a sorbent-based hydrogen purification unit using microwave power for sorbent regeneration developed by Umpqua Research Company, and a LaNi4.6Sn0.4 metal hydride produced by Hydrogen Consultants, Inc. Here we report the results of these evaluations, discuss potential architecture options, and propose future work.

Hydrogen at the Rooftop: Compact CPV-Hydrogen system to Convert Sunlight to Hydrogen

KAUST Repository

Burhan, Muhammad

2017-12-27

Despite being highest potential energy source, solar intermittency and low power density make it difficult for solar energy to compete with the conventional power plants. Highly efficient concentrated photovoltaic (CPV) system provides best technology to be paired with the electrolytic hydrogen production, as a sustainable energy source with long term energy storage. However, the conventional gigantic design of CPV system limits its market and application to the open desert fields without any rooftop installation scope, unlike conventional PV. This makes CPV less popular among solar energy customers. This paper discusses the development of compact CPV-Hydrogen system for the rooftop application in the urban region. The in-house built compact CPV system works with hybrid solar tracking of 0.1° accuracy, ensured through proposed double lens collimator based solar tracking sensor. With PEM based electrolyser, the compact CPV-hydrogen system showed 28% CPV efficiency and 18% sunlight to hydrogen (STH) efficiency, for rooftop operation in tropical region of Singapore. For plant designers, the solar to hydrogen production rating of 217 kWh/kg has been presented with 15% STH daily average efficiency, recorded from the long term field operation of the system.

Hydrogen at the Rooftop: Compact CPV-Hydrogen system to Convert Sunlight to Hydrogen

KAUST Repository

Burhan, Muhammad; Wakil Shahzad, Muhammad; Ng, Kim Choon

2017-01-01

Despite being highest potential energy source, solar intermittency and low power density make it difficult for solar energy to compete with the conventional power plants. Highly efficient concentrated photovoltaic (CPV) system provides best technology to be paired with the electrolytic hydrogen production, as a sustainable energy source with long term energy storage. However, the conventional gigantic design of CPV system limits its market and application to the open desert fields without any rooftop installation scope, unlike conventional PV. This makes CPV less popular among solar energy customers. This paper discusses the development of compact CPV-Hydrogen system for the rooftop application in the urban region. The in-house built compact CPV system works with hybrid solar tracking of 0.1° accuracy, ensured through proposed double lens collimator based solar tracking sensor. With PEM based electrolyser, the compact CPV-hydrogen system showed 28% CPV efficiency and 18% sunlight to hydrogen (STH) efficiency, for rooftop operation in tropical region of Singapore. For plant designers, the solar to hydrogen production rating of 217 kWh/kg has been presented with 15% STH daily average efficiency, recorded from the long term field operation of the system.

Hydrogen generation monitoring and mass gain analysis during the steam oxidation for Zircaloy using hydrogen and oxygen sensors

International Nuclear Information System (INIS)

Fukumoto, Michihisa; Hara, Motoi; Kaneko, Hiroyuki; Sakuraba, Takuya

2015-01-01

The oxidation behavior of Zircaloy-4 at high temperatures in a flowing Ar-H_2O (saturated at 323 K) mixed gas was investigated using hydrogen and oxygen sensors installed at a gas outlet, and the utility of the gas sensing methods by using both sensors was examined. The generated amount of hydrogen was determined from the hydrogen partial pressure continuously measured by the hydrogen sensor, and the resultant calculated oxygen amount that reacted with the specimen was in close agreement with the mass gain gravimetrically measured after the experiment. This result demonstrated that the hydrogen partial pressure measurement using a hydrogen sensor is an effective method for examining the steam oxidation of this metal as well as monitoring the hydrogen evolution. The advantage of this method is that the oxidation rate of the metal at any time as a differential quantity is able to be obtained, compared to the oxygen amount gravimetrically measured as an integral quantity. When the temperature was periodically changed in the range of 1173 K to 1523 K, highly accurate measurements could be carried out using this gas monitoring method, although reasonable measurements were not gravimetrically performed due to the fluctuating thermo-buoyancy during the experiment. A change of the oxidation rate was clearly detected at a monoclinic tetragonal transition temperature of ZrO_2. From the calculation of the water vapor partial pressure during the thermal equilibrium condition using the hydrogen and oxygen partial pressures, it became clear that a thermal equilibrium state is maintained when the isothermal condition is maintained, but is not when the temperature increases or decreases with time. Based on these results, it was demonstrated that the gas monitoring system using hydrogen and oxygen sensors is very useful for investigating the oxidation process of the Zircaloy in steam. (author)

Assessment of MHR-based hydrogen energy systems

International Nuclear Information System (INIS)

Richards, Matthew; Shenoy, Arkal; Schultz, Kenneth; Brown, Lloyd; Besenbruch, Gottfried; Handa, Norihiko; Das, Jadu

2004-01-01

Process heat from a high-temperature nuclear reactor can be used to drive a set of chemical reactions, with the net result of splitting water into hydrogen and oxygen. For example, process heat at temperatures in the range 850degC to 950degC can drive the sulfur-iodine (SI) thermochemical process to produce hydrogen with high efficiency. The SI process produces highly pure hydrogen and oxygen, with formation, decomposition, regeneration, and recycle of the intermediate chemical reagents and low-temperature heat as the only waste product. Electricity can also be used directly to split water, using conventional, low-temperature electrolysis (LTE). Hydrogen can also be produced with hybrid processes that use both process heat and electricity to generate hydrogen. An example of a hybrid process is high-temperature electrolysis (HTE), in which process heat is used to generate steam, which is then supplied to an electrolyzer to generate hydrogen. This process is of interest because the efficiency of electrolysis increases with temperature. Because of its high-temperature capability, advanced of development relative to other high-temperature reactor concepts, and passive-safety features, the Modular Helium Reactor (MHR) is well suited for producing hydrogen using nuclear energy. In this paper we investigate concepts for coupling the MHR to the SI process, LTE, and HTE. These concepts are referred to as the H2-MHR. (author)

System-level energy efficiency is the greatest barrier to development of the hydrogen economy

International Nuclear Information System (INIS)

Page, Shannon; Krumdieck, Susan

2009-01-01

Current energy research investment policy in New Zealand is based on assumed benefits of transitioning to hydrogen as a transport fuel and as storage for electricity from renewable resources. The hydrogen economy concept, as set out in recent commissioned research investment policy advice documents, includes a range of hydrogen energy supply and consumption chains for transport and residential energy services. The benefits of research and development investments in these advice documents were not fully analyzed by cost or improvements in energy efficiency or green house gas emissions reduction. This paper sets out a straightforward method to quantify the system-level efficiency of these energy chains. The method was applied to transportation and stationary heat and power, with hydrogen generated from wind energy, natural gas and coal. The system-level efficiencies for the hydrogen chains were compared to direct use of conventionally generated electricity, and with internal combustion engines operating on gas- or coal-derived fuel. The hydrogen energy chains were shown to provide little or no system-level efficiency improvement over conventional technology. The current research investment policy is aimed at enabling a hydrogen economy without considering the dramatic loss of efficiency that would result from using this energy carrier.

Multimegawatt disk generator system for space applications

International Nuclear Information System (INIS)

Solbes, H.; Iwata, H.

1988-01-01

The conceptual design of a 100 megawatt - 500 seconds disk MHD generator system suitable as a burst power source for a space based neutral particle beam (NPB) is presented. The system features two disk generators operated in the magnetic field produced by a single circular superconducting magnet. Gelled reactants are used as the energy source. The oxidizer gel includes the alkali seed. The high heat flux areas of the power train are water cooled. Heat is rejected to a hydrogen stream which is also used for cooling of the exit section. The hydrogen is also used to mitigate the effects of the exhaust products of combustion on the platform. The two disk channels are operated in parallel. A dc to dc converter consolidates the channel's output into a single 100 kilovolt dc output. Critical development issues relevant to the development of such power systems are identified and discussed. A R and D plan aimed at establishing the technical feasibility of the proposed system is also presented

Multimegawatt disk generator system for space applications

International Nuclear Information System (INIS)

Solbes, A.; Iwata, H.

1988-01-01

The conceptual design of a 100 megawatt - 500 seconds disk MHD generator system suitable as a burst power source for a space based neutral particle beam (NPB) is presented. The system features two disk generators operated in the magnetic field produced by a single circular superconducting magnet. Gelled reactants are used as the energy source. The oxidizer gel includes the alkali seed. The high heat flux areas of the power train are water cooled. Heat is rejected to a hydrogen stream which is also used for cooling of the exit section. The hydrogen is also used to mitigate the effects of the exhaust products of combustion on the platform. The two disk channels are operated in parallel. A dc to dc converter consolidates the channel's output into a single 100 kilovolt dc output

Modeling of hydrogen/deuterium dynamics and heat generation on palladium nanoparticles for hydrogen storage and solid-state nuclear fusion.

Science.gov (United States)

Tanabe, Katsuaki

2016-01-01

We modeled the dynamics of hydrogen and deuterium adsorbed on palladium nanoparticles including the heat generation induced by the chemical adsorption and desorption, as well as palladium-catalyzed reactions. Our calculations based on the proposed model reproduce the experimental time-evolution of pressure and temperature with a single set of fitting parameters for hydrogen and deuterium injection. The model we generated with a highly generalized set of formulations can be applied for any combination of a gas species and a catalytic adsorbent/absorbent. Our model can be used as a basis for future research into hydrogen storage and solid-state nuclear fusion technologies.

Study of a molten carbonate fuel cell combined heat, hydrogen and power system: Energy analysis

International Nuclear Information System (INIS)

Agll, Abdulhakim Amer A.; Hamad, Yousif M.; Hamad, Tarek A.; Thomas, Mathew; Bapat, Sushrut; Martin, Kevin B.; Sheffield, John W.

2013-01-01

Countries around the world are trying to use alternative fuels and renewable energy to reduce the energy consumption and greenhouse gas emissions. Biogas contains methane is considered a potential source of clean renewable energy. This paper discusses the design of a combined heat, hydrogen and power system, which generated by methane with use of Fuelcell, for the campus of Missouri University of Science and Technology located in Rolla, Missouri, USA. An energy flow and resource availability study was performed to identify sustainable type and source of feedstock needed to run the Fuelcell at its maximum capacity. FuelCell Energy's DFC1500 unit (a molten carbonate Fuelcell) was selected as the Fuelcell for the tri-generation (heat, hydrogen and electric power) system. This tri-generation system provides electric power to the campus, thermal energy for heating the anaerobic digester, and hydrogen for transportation, backup power and other applications on the campus. In conclusion, the combined heat, hydrogen and power system reduces fossil fuel usage, and greenhouse gas emissions at the university campus. -- Highlights: • Combined heat, hydrogen and power (CHHP) using a molten carbonate fuel cell. • Energy saving and alternative fuel of the products are determined. • Energy saving is increased when CHHP technology is implemented. • CHHP system reduces the greenhouse gas emissions and fuel consumption

Renewable solar hydrogen production and utilization

International Nuclear Information System (INIS)

Bakos, J.

2006-01-01

There is a tremendous opportunity to generate large quantities of hydrogen from low grade and economical sources of methane including landfill gas, biogas, flare gas, and coal bed methane. The environmental benefits of generating hydrogen using renewable energy include significant greenhouse gas and air contaminant reductions. Solar Hydrogen Energy Corporation (SHEC LABS) recently constructed and demonstrated a Dry Fuel Reforming (DFR) hydrogen generation system that is powered primarily by sunlight focusing-mirrors in Tempe, Arizona. The system comprises a solar mirror array, a temperature controlling shutter system, and two thermo-catalytic reactors to convert methane, carbon dioxide, and water into hydrogen. This process has shown that solar hydrogen generation is feasible and cost-competitive with traditional hydrogen production. The presentation will provide the following: An overview of the results of the testing conducted in Tempe, Arizona; A look at the design and installation of the scaled-up technology site at a landfill site in Canada; An examination of the economic and environmental benefits of renewable hydrogen production using solar energy

Electroless Nickel-Based Catalyst for Diffusion Limited Hydrogen Generation through Hydrolysis of Borohydride

Directory of Open Access Journals (Sweden)

Shannon P. Anderson

2013-07-01

Full Text Available Catalysts based on electroless nickel and bi-metallic nickel-molybdenum nanoparticles were synthesized for the hydrolysis of sodium borohydride for hydrogen generation. The catalysts were synthesized by polymer-stabilized Pd nanoparticle-catalyzation and activation of Al2O3 substrate and electroless Ni or Ni-Mo plating of the substrate for selected time lengths. Catalytic activity of the synthesized catalysts was tested for the hydrolyzation of alkaline-stabilized NaBH4 solution for hydrogen generation. The effects of electroless plating time lengths, temperature and NaBH4 concentration on hydrogen generation rates were analyzed and discussed. Compositional analysis and surface morphology were carried out for nano-metallized Al2O3 using Scanning Electron Micrographs (SEM and Energy Dispersive X-Ray Microanalysis (EDAX. The as-plated polymer-stabilized electroless nickel catalyst plated for 10 min and unstirred in the hydrolysis reaction exhibited appreciable catalytic activity for hydrolysis of NaBH4. For a zero-order reaction assumption, activation energy of hydrogen generation using the catalyst was estimated at 104.6 kJ/mol. Suggestions are provided for further work needed prior to using the catalyst for portable hydrogen generation from aqueous alkaline-stabilized NaBH4 solution for fuel cells.

Canadian Hydrogen Association workshop on building Canadian strength with hydrogen systems. Proceedings

International Nuclear Information System (INIS)

2006-01-01

The Canadian Hydrogen Association workshop on 'Building Canadian Strength with Hydrogen Systems' was held in Montreal, Quebec, Canada on October 19-20, 2006. Over 100 delegates attended the workshop and there were over 50 presentations made. The Canadian Hydrogen Association (CHA) promotes the development of a hydrogen infrastructure and the commercialization of new, efficient and economic methods that accelerate the adoption of hydrogen technologies that will eventually replace fossil-based energy systems to reduce greenhouse gas emissions. This workshop focused on defining the strategic direction of research and development that will define the future of hydrogen related energy developments across Canada. It provided a forum to strengthen the research, development and innovation linkages among government, industry and academia to build Canadian strength with hydrogen systems. The presentations described new technologies and the companies that are making small scale hydrogen and hydrogen powered vehicles. Other topics of discussion included storage issues, hydrogen safety, competition in the hydrogen market, hydrogen fuel cell opportunities, nuclear-based hydrogen production, and environmental impacts

Reforming water to generate hydrogen using mechanical alloy

International Nuclear Information System (INIS)

Pena F, D. L.

2016-01-01

The objective of this research was to generate a hydrogen production system by means of mechanical milling, in which 0.1 g of magnesium were weighed using a volume of 300 μL for each water solvent (H_2O) and methanol (CH_3OH) in a container to start mechanical milling for 2, 4 and 6 h. Once the mechanical milling was finished, the hydrogen that was produced every two hours was measured to determine the appropriate milling time in the production, also in each period of time samples of the powders produced during the milling of Mg were taken, in this process we used characterization techniques such as: X-ray diffraction at an angle of 2θi 5 and 2θf 90 degrees and scanning electron microscopy, taking micrographs of 100, 500, 1000 and 5000 magnifications. According to the mechanical milling results hydrogen was obtained when using water, as well as with methanol. In the techniques of X-ray diffraction characterization different results were obtained before and after the milling, since by the diffractogram s is possible to observe how the magnesium to be put in the mechanical milling along with the water and methanol was diminishing to be transformed into hydroxide and magnesium oxide, as well as in the micrographs taken with scanning electron microscopy the change in the magnesium morphology to hydroxide and magnesium oxide is observed. (Author)

Pd/C Synthesized with Citric Acid: An Efficient Catalyst for Hydrogen Generation from Formic Acid/Sodium Formate

Science.gov (United States)

Wang, Zhi-Li; Yan, Jun-Min; Wang, Hong-Li; Ping, Yun; Jiang, Qing

2012-01-01

A highly efficient hydrogen generation from formic acid/sodium formate aqueous solution catalyzed by in situ synthesized Pd/C with citric acid has been successfully achieved at room temperature. Interestingly, the presence of citric acid during the formation and growth of the Pd nanoparticles on carbon can drastically enhance the catalytic property of the resulted Pd/C, on which the conversion and turnover frequency for decomposition of formic acid/sodium formate system can reach the highest values ever reported of 85% within 160 min and 64 mol H2 mol−1 catalyst h−1, respectively, at room temperature. The present simple, low cost, but highly efficient CO-free hydrogen generation system at room temperature is believed to greatly promote the practical application of formic acid system on fuel cells. PMID:22953041

Prospects for hydrogen in the German energy system

International Nuclear Information System (INIS)

Hake, J.-F.; Linssen, J.; Walbeck, M.

2006-01-01

The focus of the paper concerns the current discussion on the contribution of the hydrogen economy to a 'sustainable energy system'. It considers whether advantages for the environmental situation and energy carrier supply can be expected from the already visible future characteristics of hydrogen as a new secondary energy carrier. Possible production paths for hydrogen from hydrocarbon-based, renewable or carbon-reduced/-free primary energy carriers are evaluated with respect to primary energy use and CO 2 emissions from the fuel cycle. Hydrogen has to be packaged by compression or liquefaction, transported by surface vehicles or pipelines, stored and transferred to the end user. Whether generated by electrolysis or by reforming, and even if produced locally at filling stations, the gaseous or liquid hydrogen has to undergo these market processes before it can be used by the customer. In order to provide an idea of possible markets with special emphasis on the German energy sector, a technical systems analysis of possible hydrogen applications is performed for the stationary, mobile and portable sector. Furthermore, different 'business as usual' scenarios are analysed for Germany, Europe and the World concerning end energy use in different sectors. The very small assumed penetration of hydrogen in the analysed scenarios up to the year 2050 indicates that the hydrogen economy is a long-term option. With reference to the assumed supply paths and analysed application possibilities, hydrogen can be an option for clean energy use if hydrogen can be produced with carbon-reduced or -free primary energy carriers like renewable energy or biomass. However, the energetic use of hydrogen competes with the direct use of clean primary energy and/or with the use of electric energy based on renewable primary energy. As a substitution product for other secondary energy carriers hydrogen is therefore under pressure of costs and/or must have advantages in comparison to the use of

A synergetic use of hydrogen and fuel cells in human spaceflight power systems

Science.gov (United States)

Belz, S.

2016-04-01

Hydrogen is very flexible in different fields of application of energy conversion. It can be generated by water electrolysis. Stored in tanks it is available for re-electrification by fuel cells. But it is not only the power system, which benefits from use of hydrogen, but also the life support system, which can contain hydrogen consuming technologies for recycling management (e.g. carbon dioxide removal and waste combustion processes). This paper points out various fields of hydrogen use in a human spaceflight system. Depending on mission scenarios, shadow phases, and the need of energy storage, regenerative fuel cell systems can be more efficient than secondary batteries. Here, different power storage concepts are compared by equivalent system mass calculation, thus including impact in the peripheral structure (volume, thermal management, etc.) on the space system. It is also focused on the technical integration aspect, e.g. which peripheral components have to be adapted when hydrogen is also used for life support technologies and what system mass benefit can be expected. Finally, a recommendation is given for the following development steps for a synergetic use of hydrogen and fuel cells in human spaceflight power systems.

Integration of direct carbon and hydrogen fuel cells for highly efficient power generation from hydrocarbon fuels

Energy Technology Data Exchange (ETDEWEB)

Muradov, Nazim; Choi, Pyoungho; Smith, Franklyn; Bokerman, Gary [Florida Solar Energy Center, University of Central Florida, 1679 Clearlake Road, Cocoa, FL 32922-5703 (United States)

2010-02-15

In view of impending depletion of hydrocarbon fuel resources and their negative environmental impact, it is imperative to significantly increase the energy conversion efficiency of hydrocarbon-based power generation systems. The combination of a hydrocarbon decomposition reactor with a direct carbon and hydrogen fuel cells (FC) as a means for a significant increase in chemical-to-electrical energy conversion efficiency is discussed in this paper. The data on development and operation of a thermocatalytic hydrocarbon decomposition reactor and its coupling with a proton exchange membrane FC are presented. The analysis of the integrated power generating system including a hydrocarbon decomposition reactor, direct carbon and hydrogen FC using natural gas and propane as fuels is conducted. It was estimated that overall chemical-to-electrical energy conversion efficiency of the integrated system varied in the range of 49.4-82.5%, depending on the type of fuel and FC used, and CO{sub 2} emission per kW{sub el}h produced is less than half of that from conventional power generation sources. (author)

Helium refrigeration system for hydrogen liquefaction applications

Science.gov (United States)

Nair, J. Kumar, Sr.; Menon, RS; Goyal, M.; Ansari, NA; Chakravarty, A.; Joemon, V.

2017-02-01

Liquid hydrogen around 20 K is used as cold moderator for generating “cold neutron beam” in nuclear research reactors. A cryogenic helium refrigeration system is the core upon which such hydrogen liquefaction applications are built. A thermodynamic process based on reversed Brayton cycle with two stage expansion using high speed cryogenic turboexpanders (TEX) along with a pair of compact high effectiveness process heat exchangers (HX), is well suited for such applications. An existing helium refrigeration system, which had earlier demonstrated a refrigeration capacity of 470 W at around 20 K, is modified based on past operational experiences and newer application requirements. Modifications include addition of a new heat exchanger to simulate cryogenic process load and two other heat exchangers for controlling the temperatures of helium streams leading out to the application system. To incorporate these changes, cryogenic piping inside the cold box is suitably modified. This paper presents process simulation, sizing of new heat exchangers as well as fabrication aspects of the modified cryogenic process piping.

Hydrogen generation and storage from hydrolysis of sodium borohydride in batch reactors

Energy Technology Data Exchange (ETDEWEB)

Pinto, A.M.F.R.; Falcao, D.S. [Departamento de Eng. Quimica, Centro de Estudos de Fenomenos de Transporte, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); Silva, R.A.; Rangel, C.M. [Instituto Nacional de Engenharia e Tecnologia e Inovacao, Paco do Lumiar 22, 1649-038 (Portugal)

2006-08-15

The catalytic hydrolysis of alkaline sodium borohydride (NaBH{sub 4}) solution was studied using a non-noble; nickel-based powered catalyst exhibiting strong activity even after long time storage. This easy-to-prepare catalyst showed an enhanced activity after being recovered from previous use. The effects of temperature, NaBH{sub 4} concentration, NaOH concentration and pressure on the hydrogen generation rate were investigated. Particular importance has the effect of pressure, since the maximum reached pressure of hydrogen is always substantially lower than predictions (considering 100% conversion) due to solubility effects. The solubility of hydrogen is greatly enhanced by the rising pressure during reaction, leading to storage of hydrogen in the liquid phase. This effect can induce new ways of using this type of catalyst and reactor for the construction of hydrogen generators and even containers for portable and in situ applications. (author)

Modeling of hydrogen/deuterium dynamics and heat generation on palladium nanoparticles for hydrogen storage and solid-state nuclear fusion

Directory of Open Access Journals (Sweden)

Katsuaki Tanabe

2016-01-01

Full Text Available We modeled the dynamics of hydrogen and deuterium adsorbed on palladium nanoparticles including the heat generation induced by the chemical adsorption and desorption, as well as palladium-catalyzed reactions. Our calculations based on the proposed model reproduce the experimental time-evolution of pressure and temperature with a single set of fitting parameters for hydrogen and deuterium injection. The model we generated with a highly generalized set of formulations can be applied for any combination of a gas species and a catalytic adsorbent/absorbent. Our model can be used as a basis for future research into hydrogen storage and solid-state nuclear fusion technologies.

The Potential for Low-Temperature Abiotic Hydrogen Generation and a Hydrogen-Driven Deep Biosphere

Science.gov (United States)

Huang, Shanshan; Thorseth, Ingunn H.

2011-01-01

Abstract The release and oxidation of ferrous iron during aqueous alteration of the mineral olivine is known to reduce aqueous solutions to such extent that molecular hydrogen, H2, forms. H2 is an efficient energy carrier and is considered basal to the deep subsurface biosphere. Knowledge of the potential for H2 generation is therefore vital to understanding the deep biosphere on Earth and on extraterrestrial bodies. Here, we provide a review of factors that may reduce the potential for H2 generation with a focus on systems in the core temperature region for thermophilic to hyperthermophilic microbial life. We show that aqueous sulfate may inhibit the formation of H2, whereas redox-sensitive compounds of carbon and nitrogen are unlikely to have significant effect at low temperatures. In addition, we suggest that the rate of H2 generation is proportional to the dissolution rate of olivine and, hence, limited by factors such as reactive surface areas and the access of water to fresh surfaces. We furthermore suggest that the availability of water and pore/fracture space are the most important factors that limit the generation of H2. Our study implies that, because of large heat flows, abundant olivine-bearing rocks, large thermodynamic gradients, and reduced atmospheres, young Earth and Mars probably offered abundant systems where microbial life could possibly have emerged. Key Words: Serpentinization—Olivine—Hydrogen—Deep biosphere—Water—Mars. Astrobiology 11, 711–724. PMID:21923409

Fuel Cell Power Model Version 2: Startup Guide, System Designs, and Case Studies. Modeling Electricity, Heat, and Hydrogen Generation from Fuel Cell-Based Distributed Energy Systems

Energy Technology Data Exchange (ETDEWEB)

Steward, D.; Penev, M.; Saur, G.; Becker, W.; Zuboy, J.

2013-06-01

This guide helps users get started with the U.S. Department of Energy/National Renewable Energy Laboratory Fuel Cell Power (FCPower) Model Version 2, which is a Microsoft Excel workbook that analyzes the technical and economic aspects of high-temperature fuel cell-based distributed energy systems with the aim of providing consistent, transparent, comparable results. This type of energy system would provide onsite-generated heat and electricity to large end users such as hospitals and office complexes. The hydrogen produced could be used for fueling vehicles or stored for later conversion to electricity.

Catalytic hydrolysis of ammonia borane for hydrogen generation using cobalt nanocluster catalyst supported on polydopamine functionalized multiwalled carbon nanotube

International Nuclear Information System (INIS)

Arthur, Ernest Evans; Li, Fang; Momade, Francis W.Y.; Kim, Hern

2014-01-01

Hydrogen was generated from ammonia borane complex by hydrolysis using cobalt nanocluster catalyst supported on polydopamine functionalized MWCNTs (multi-walled carbon nanotubes). The impregnation-chemical reduction method was used for the preparation of the supported catalyst. The nanocluster catalyst support was formed by in-situ oxidative polymerization of dopamine on the MWCNTs in alkaline solution at room temperature. The structural and physical–chemical properties of the nanocluster catalyst were characterized by FT-IR (Fourier transform infrared spectroscopy), EDX (energy-dispersive X-ray spectroscopy), SEM (scanning electron microscope), XRD (X-ray diffraction) and TEM (transmission electron microscopy). The nanocluster catalyst showed good catalytic activity for the hydrogen generation from aqueous ammonia borane complex. A reusability test to determine the practical usage of the catalyst was also investigated. The result revealed that the catalyst maintained an appreciable catalytic performance and stability in terms of its reusability after three cycle of reuse for the hydrolysis reaction. Also, the activation energy for the hydrolysis of ammonia borane complex was estimated to be 50.41 kJmol −1 , which is lower than the values of some of the reported catalyst. The catalyst can be considered as a promising candidate in developing highly efficient portable hydrogen generation systems such as PEMFC (proton exchange membrane fuel cells). - Highlights: • Co/Pdop-o-MWCNT (Pdop functionalized MWCNT supported cobalt nanocluster) catalyst was synthesized for hydrogen generation. • It is an active catalyst for hydrogen generation via hydrolysis of ammonia borane. • It showed good stability in terms of reusability for the hydrogen generation

Lessons learned from hydrogen generation and burning during the TMI-2 event

International Nuclear Information System (INIS)

Henrie, J.O.; Postma, A.K.

1987-05-01

This document summarizes what has been learned from generation of hydrogen in the reactor core and the hydrogen burn that occurred in the containment building of the Three Mile Island Unit No. 2 (TMI-2) nuclear power plant on March 28, 1979. During the TMI-2 loss-of-coolant accident (LOCA), a large quantity of hydrogen was generated by a zirconium-water reaction. The hydrogen burn that occurred 9 h and 50 min after the initiation of the TMI-2 accident went essentially unnoticed for the first few days. Even through the burn increased the containment gas temperature and pressure to 1200 0 F (650 0 C) and 29 lb/in 2 (200 kPa) gage, there was no serious threat to the containment building. The processes, rates, and quantities of hydrogen gas generated and removed during and following the LOCA are described in this report. In addition, the methods which were used to define the conditions that existed in the containment building before, during, and after the hydrogen burn are described. The results of data evaluations and engineering calculations are presented to show the pressure and temperature histories of the atmosphere in various containment segments during and after the burn. Material and equipment in reactor containment buildings can be protected from burn damage by the use of relatively simple enclosures or insulation

International Clean Energy System Using Hydrogen Conversion (WE-NET). subtask 3. Conceptual design of the total system; Suiso riyo kokusai clean energy system gijutsu (WE-NET). subtask 3. Zentai system gainen sekkei

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

This paper describes the research result on the conceptual design of the total system for the WE-NET project in 1996. Basic conditions are as follows: solid polymer water electrolysis, hydrogen combustion turbine power generation, hydrogen transport/storage through ammonia medium, power generation scale of 1000-4000MW (2-5 yen/kWh), and transport distance of 5000-20000km between supply and consumption places. The system efficiency was estimated to be 68% and 23% at an ammonia arrival time and power sending end, respectively, and it was dependent on a transport distance, while no power generation scale. The power cost was estimated to be 7 yen/Mcal and 33 yen/kWh, respectively. The system efficiency at a sending end was lower by 15% and 2% than that of the liquid hydrogen and methanol system, while the power cost was higher by 0 and 8 yen/kWh, respectively. It was necessary for loss reduction of this ammonia system to develop a new high-efficiency ammonia synthesis process, and hydrogen separation (decomposition/refining) process. 80 figs., 52 tabs.

Nickel-hydrogen bipolar battery system

Science.gov (United States)

Thaller, L. H.

1982-01-01

Rechargeable nickel-hydrogen systems are described that more closely resemble a fuel cell system than a traditional nickel-cadmium battery pack. This was stimulated by the currently emerging requirements related to large manned and unmanned low Earth orbit applications. The resultant nickel-hydrogen battery system should have a number of features that would lead to improved reliability, reduced costs as well as superior energy density and cycle lives as compared to battery systems constructed from the current state-of-the-art nickel-hydrogen individual pressure vessel cells.

Utilization of Aluminum Waste with Hydrogen and Heat Generation

Science.gov (United States)

Buryakovskaya, O. A.; Meshkov, E. A.; Vlaskin, M. S.; Shkolnokov, E. I.; Zhuk, A. Z.

2017-10-01

A concept of energy generation via hydrogen and heat production from aluminum containing wastes is proposed. The hydrogen obtained by oxidation reaction between aluminum waste and aqueous solutions can be supplied to fuel cells and/or infrared heaters for electricity or heat generation in the region of waste recycling. The heat released during the reaction also can be effectively used. The proposed method of aluminum waste recycling may represent a promising and cost-effective solution in cases when waste transportation to recycling plants involves significant financial losses (e.g. remote areas). Experiments with mechanically dispersed aluminum cans demonstrated that the reaction rate in alkaline solution is high enough for practical use of the oxidation process. In theexperiments aluminum oxidation proceeds without any additional aluminum activation.

Technical feasibility and financial analysis of hybrid wind-photovoltaic system with hydrogen storage for Cooma

Energy Technology Data Exchange (ETDEWEB)

Shakya, B.D.; Aye, L. [Melbourne Univ., Victoria (Australia). Dept. of Civil and Environmental Engineering; Musgrave, P. [Snowy Hydro Ltd., Cooma, NSW (Australia)

2005-01-01

The feasibility of a stand-alone hybrid wind-photovoltaic (PV) system incorporating compressed hydrogen gas storage was studied for Cooma (Australia). Cooma has an average annual solar and wind energy availability of 1784 and 932 kWh/m{sup 2}, respectively. A system with 69 kWh{sub e}/day (load) and 483 kWh{sub e}(storage) was studied. Hydrogen is generated in electrolysers using excess electricity from the system. The system components were selected according to their availability and cost. The 'discounted cash flow' method, with the 'levelized energy cost' (LEC) as a financial indicator was used for analysis. Configurations with PV% of 100, 60, 12 and zero were analysed. The lowest LEC of AU $2.52/kWh{sub e} was found for 100% PV. The cost of hydrogen generation from 100% PV was AU $692/GJ of hydrogen. Fifty-two percent of the total project costs were due to the electrolyser. Hence, a reduction in the electrolyser cost would reduce the cost of the overall system. (Author)

Generating para-water from para-hydrogen: A Gedankenexperiment.

Science.gov (United States)

Ivanov, Konstantin L; Bodenhausen, Geoffrey

2018-07-01

A novel conceptual approach is described that is based on the transfer of hyperpolarization from para-hydrogen in view of generating a population imbalance between the two spin isomers of H 2 O. The approach is analogous to SABRE (Signal Amplification By Reversible Exchange) and makes use of the transfer of spin order from para-hydrogen to H 2 O in a hypothetical organometallic complex. The spin order transfer is expected to be most efficient at avoided level crossings. The highest achievable enrichment levels of para- and ortho-water are discussed. Copyright © 2018 Elsevier Inc. All rights reserved.

Limits for hydrogen production of a solar - hydrogen system in Cuernavaca, Mexico

International Nuclear Information System (INIS)

Arriaga, H.L.G.; Gutierrez, S.L.; Cano, U.

2006-01-01

In this work experimental data are used in order to estimate the production of hydrogen as a function of irradiance of a direct-interconnection of solar panel system with a SPE (Solid Polymer Electrolyte) electrolyzer (also Solar-Hydrogen system). The solar - hydrogen system, consists of a photovoltaic solar array of 36 panels (75 Watts each) of monocrystalline silicon interconnected with an electrolyzer stack of 25 cells (around 100 cm 2 of geometrical area) with a maximum hydrogen production of 1 Nm 3 /h. By the use of voltage, current density, energy consumption values of the whole solar-hydrogen system, an average efficiency up to 5% was estimated and an average of 3,800 NL of hydrogen per day can be expected. Also the maximum hydrogen production for the months of July and December (sunniest and least sunny months in the location) is predicted. (authors)

Limits for hydrogen production of a solar - hydrogen system in Cuernavaca, Mexico

Energy Technology Data Exchange (ETDEWEB)

Arriaga, H.L.G.; Gutierrez, S.L.; Cano, U. [Instituto de Investigaciones Electricas Av. Reforma 113, col. Palmira c.p.62490 Cuernavaca Morelos (Mexico)

2006-07-01

In this work experimental data are used in order to estimate the production of hydrogen as a function of irradiance of a direct-interconnection of solar panel system with a SPE (Solid Polymer Electrolyte) electrolyzer (also Solar-Hydrogen system). The solar - hydrogen system, consists of a photovoltaic solar array of 36 panels (75 Watts each) of monocrystalline silicon interconnected with an electrolyzer stack of 25 cells (around 100 cm{sup 2} of geometrical area) with a maximum hydrogen production of 1 Nm{sup 3}/h. By the use of voltage, current density, energy consumption values of the whole solar-hydrogen system, an average efficiency up to 5% was estimated and an average of 3,800 NL of hydrogen per day can be expected. Also the maximum hydrogen production for the months of July and December (sunniest and least sunny months in the location) is predicted. (authors)

Development of a low-cost oxy-hydrogen bio-fuel cell for generation of electricity using Nostoc as a source of hydrogen

Energy Technology Data Exchange (ETDEWEB)

Sangeeta Dawar; Behera, B.K. [Maharshi Dayanand University, Rohtak (India). Dept. of Biosciences; Prasanna Mohanty [Jawaharlal Nehru University, New Delhi (India). School of Life Sciences

1998-10-10

An oxy-hydrogen bio-fuel cell, based on a carbon-carbon electrode has been fabricated. The electrode pellets were prepared by taking carbon powder mixed with polyvinylalcohol as a binder. The anode was charged with Co-Al spinel mixed oxide at 700{sup o}C, 30% KOH acted as an electrolyte. For the cyanobacterial bioreactor, a potential heterocystous blue green alga of Nostoc spp. has been used for hydrogen production and electrical energy generation. Various nutrient enrichment techniques are employed to increase the hydrogen generation efficiency of the algae. One litre free cell algal reactor attached to the fuel cell, at the anode end for hydrogen gas input, generated about 300 mV of voltage and 100 mA of current. Our present findings on the development of a low cost fuel cell with high efficiency of current output may be helpful in commercializing this technology. (author)

Sensitivity analyses on in-vessel hydrogen generation for KNGR

International Nuclear Information System (INIS)

Kim, See Darl; Park, S.Y.; Park, S.H.; Park, J.H.

2001-03-01

Sensitivity analyses for the in-vessel hydrogen generation, using the MELCOR program, are described in this report for the Korean Next Generation Reactor. The typical accident sequences of a station blackout and a large LOCA scenario are selected. A lower head failure model, a Zircaloy oxidation reaction model and a B 4 C reaction model are considered for the sensitivity parameters. As for the base case, 1273.15K for a failure temperature of the penetrations or the lower head, an Urbanic-Heidrich correlation for the Zircaloy oxidation reaction model and the B 4 C reaction model are used. Case 1 used 1650K as the failure temperature for the penetrations and Case 2 considered creep rupture instead of penetration failure. Case 3 used a MATPRO-EG and G correlation for the Zircaloy oxidation reaction model and Case 4 turned off the B 4 C reaction model. The results of the studies are summarized below : (1) When the penetration failure temperature is higher, or the creep rupture failure model is considered, the amount of hydrogen increases for two sequences. (2) When the MATPRO-EG and G correlation for a Zircaloy oxidation reaction is considered, the amount of hydrogen is less than the Urbanic-Heidrich correlation (Base case) for both scenarios. (3) When the B 4 C reaction model turns off, the amount of hydrogen decreases for two sequences

Energy infrastructure: hydrogen energy system

Energy Technology Data Exchange (ETDEWEB)

Veziroglu, T N

1979-02-01

In a hydrogen system, hydrogen is not a primary source of energy, but an intermediary, an energy carrier between the primary energy sources and the user. The new unconventional energy sources, such as nuclear breeder reactors, fusion reactors, direct solar radiation, wind energy, ocean thermal energy, and geothermal energy have their shortcomings. These shortcomings of the new sources point out to the need for an intermediary energy system to form the link between the primary energy sources and the user. In such a system, the intermediary energy form must be transportable and storable; economical to produce; and if possible renewable and pollution-free. The above prerequisites are best met by hydrogen. Hydrogen is plentiful in the form of water. It is the cheapest synthetic fuel to manufacture per unit of energy stored in it. It is the least polluting of all of the fuels, and is the lightest and recyclable. In the proposed system, hydrogen would be produced in large plants located away from the consumption centers at the sites where primary new energy sources and water are available. Hydrogen would then be transported to energy consumption centers where it would be used in every application where fossil fuels are being used today. Once such a system is established, it will never be necessary to change to any other energy system.

An examination of isolated, stationary, hydrogen power systems supplied by renewables: component and system issues and criteria necessary for successful worldwide deployment

Energy Technology Data Exchange (ETDEWEB)

Rambach, G. D. [Energy and Environmental Engineering Center, Desert Research Institute, Reno, NV (United States)

1999-12-01

The premise of this paper is that remote, stationary power systems, based on indigenous renewable energy sources, are an ideal market entry opportunity for hydrogen, but that the deployment of isolated power systems relying on hydrogen as the energy storage medium requires complex and comprehensive planning and design considerations to provide for successful market entry strategies and appropriate systems engineering. Accordingly, this paper sets out to discuss the criteria and the framework necessary to determine how to successfully deploy any specific system or to plan a global marketing strategy. Details of the indigenous intermittent energy sources (wind turbines, solar photovoltaic, micro-hydroelectric, etc), primary power-to-hydrogen conversion systems, hydrogen storage methods, and hydrogen-to-electricity conversion systems (hydrogen-internal combustion engine generator set, hydrogen fuel cells) are described, along with the criteria for technically and commercially successful deployment of any renewable utility power system that employs energy storage.2 refs., 4 figs.

Development of a high-efficiency hydrogen generator for fuel cells for distributed power generation

Energy Technology Data Exchange (ETDEWEB)

Duraiswamy, K.; Chellappa, Anand [Intelligent Energy, 2955 Redondo Ave., Long Beach, CA 90806 (United States); Smith, Gregory; Liu, Yi; Li, Mingheng [Department of Chemical and Materials Engineering, California State Polytechnic University, Pomona, CA 91768 (United States)

2010-09-15

A collaborative effort between Intelligent Energy and Cal Poly Pomona has developed an adsorption enhanced reformer (AER) for hydrogen generation for use in conjunction with fuel cells in small sizes. The AER operates at a lower temperature (about 500 C) and has a higher hydrogen yield and purity than those in the conventional steam reforming. It employs ceria supported rhodium as the catalyst and potassium-promoted hydrotalcites to remove carbon dioxide from the products. A novel pulsing feed concept is developed for the AER operation to allow a deeper conversion of the feedstock to hydrogen. Continuous production of near fuel-cell grade hydrogen is demonstrated in the AER with four packed beds running alternately. In the best case of methane reforming, the overall conversion to hydrogen is 92% while the carbon dioxide and carbon monoxide concentrations in the production stream are on the ppm level. The ratio of carbon dioxide in the regeneration exhaust to the one in the product stream is on the order of 10{sup 3}. (author)

Low-cost storage options for solar hydrogen systems for remote area power supply

International Nuclear Information System (INIS)

Suhaib Muhammad Ali; John Andrews

2006-01-01

Equipment for storing hydrogen gas under pressure typically accounts for a significant proportion of the total capital cost of solar-hydrogen systems for remote area power supply (RAPS). RAPS remain a potential early market for renewable energy - hydrogen systems because of the relatively high costs of conventional energy sources in remote regions. In the present paper the storage requirements of PV-based solar-hydrogen RAPS systems employing PEM electrolysers and fuel cells to meet a range of typical remote area daily and annual demand profiles are investigated using a spread sheet-based simulation model. It is found that as the costs of storage are lowered the requirement for longer-term storage from summer to winter is increased with consequent potential gains in the overall economics of the solar-hydrogen system. In many remote applications, there is ample space for hydrogen storages with relatively large volumes. Hence it may be most cost-effective to store hydrogen at low to medium pressures achievable by using PEM electrolysers directly to generate the hydrogen at the pressures required, without a requirement for separate electrically-driven compressors. The latter add to system costs while requiring significant parasitic electricity consumption. Experimental investigations into a number of low-cost storage options including plastic tanks and low-to-medium pressure metal and composite cylinders are reported. On the basis of these findings, the economics of solar-hydrogen RAPS systems employing large-volume low-cost storage are investigated. (authors)

Synchronization Methods for Three Phase Distributed Power Generation Systems

DEFF Research Database (Denmark)

Timbus, Adrian Vasile; Teodorescu, Remus; Blaabjerg, Frede

2005-01-01

Nowadays, it is a general trend to increase the electricity production using Distributed Power Generation Systems (DPGS) based on renewable energy resources such as wind, sun or hydrogen. If these systems are not properly controlled, their connection to the utility network can generate problems...... on the grid side. Therefore, considerations about power generation, safe running and grid synchronization must be done before connecting these systems to the utility network. This paper is mainly dealing with the grid synchronization issues of distributed systems. An overview of the synchronization methods...

Design and exergetic analysis of a novel carbon free tri-generation system for hydrogen, power and heat production from natural gas, based on combined solid oxide fuel and electrolyser cells

Energy Technology Data Exchange (ETDEWEB)

Perdikaris, N.; Hofmann, Ph.; Spyrakis, S. [Laboratory of Steam Boilers and Thermal Plants, School of Mechanical Engineering, Thermal Engineering Section, National Technical University of Athens, 9 Heroon Polytechniou Ave., Zografou, 15780 Athens (Greece); Panopoulos, K.D. [Institute for Solid Fuels Technology and Applications, Centre for Research and Technology Hellas, 4th km N.R. Ptolemais-Kozani, P.O. Box 95, 50200 Ptolemais (Greece); Kakaras, E. [Laboratory of Steam Boilers and Thermal Plants, School of Mechanical Engineering, Thermal Engineering Section, National Technical University of Athens, 9 Heroon Polytechniou Ave., Zografou, 15780 Athens (Greece); Institute for Solid Fuels Technology and Applications, Centre for Research and Technology Hellas, 4th km N.R. Ptolemais-Kozani, P.O. Box 95, 50200 Ptolemais (Greece)

2010-03-15

The Solid Oxide Cells (SOCs) are able to operate in two modes: (a) the Solid Oxide Fuel Cells (SOFCs) that produce electricity and heat and (b) the Solid Oxide Electrolyser Cells (SOEC) that consume electricity and heat to electrolyse water and produce hydrogen and oxygen. The present paper presents a carbon free SOEC/SOFC combined system for the production of hydrogen, electricity and heat (tri-generation) from natural gas fuel. Hydrogen can be locally used as automobile fuel whereas the oxygen produced in the SOEC is used to combust the depleted fuel from the SOFC, which is producing electricity and heat from natural gas. In order to achieve efficient carbon capture in such a system, water steam should be used as the SOEC anode sweep gas, to allow the production of nitrogen free flue gases. The SOEC and SOFC operations were matched through modeling of all components in Aspenplus trademark. The exergetic efficiency of the proposed decentralised system is 28.25% for power generation and 18.55% for production of hydrogen. The system is (a) carbon free because it offers an almost pure pressurised CO{sub 2} stream to be driven for fixation via parallel pipelines to the natural gas feed, (b) does not require any additional water for its operation and (c) offers 26.53% of its energetic input as hot water for applications. (author)

Proton-coupled electron transfer versus hydrogen atom transfer: generation of charge-localized diabatic states.

Science.gov (United States)

Sirjoosingh, Andrew; Hammes-Schiffer, Sharon

2011-03-24

The distinction between proton-coupled electron transfer (PCET) and hydrogen atom transfer (HAT) mechanisms is important for the characterization of many chemical and biological processes. PCET and HAT mechanisms can be differentiated in terms of electronically nonadiabatic and adiabatic proton transfer, respectively. In this paper, quantitative diagnostics to evaluate the degree of electron-proton nonadiabaticity are presented. Moreover, the connection between the degree of electron-proton nonadiabaticity and the physical characteristics distinguishing PCET from HAT, namely, the extent of electronic charge redistribution, is clarified. In addition, a rigorous diabatization scheme for transforming the adiabatic electronic states into charge-localized diabatic states for PCET reactions is presented. These diabatic states are constructed to ensure that the first-order nonadiabatic couplings with respect to the one-dimensional transferring hydrogen coordinate vanish exactly. Application of these approaches to the phenoxyl-phenol and benzyl-toluene systems characterizes the former as PCET and the latter as HAT. The diabatic states generated for the phenoxyl-phenol system possess physically meaningful, localized electronic charge distributions that are relatively invariant along the hydrogen coordinate. These diabatic electronic states can be combined with the associated proton vibrational states to generate the reactant and product electron-proton vibronic states that form the basis of nonadiabatic PCET theories. Furthermore, these vibronic states and the corresponding vibronic couplings may be used to calculate rate constants and kinetic isotope effects of PCET reactions.

Hydrogen economy

Energy Technology Data Exchange (ETDEWEB)

Pahwa, P.K.; Pahwa, Gulshan Kumar

2013-10-01

In the future, our energy systems will need to be renewable and sustainable, efficient and cost-effective, convenient and safe. Hydrogen has been proposed as the perfect fuel for this future energy system. The availability of a reliable and cost-effective supply, safe and efficient storage, and convenient end use of hydrogen will be essential for a transition to a hydrogen economy. Research is being conducted throughout the world for the development of safe, cost-effective hydrogen production, storage, and end-use technologies that support and foster this transition. This book discusses hydrogen economy vis-a-vis sustainable development. It examines the link between development and energy, prospects of sustainable development, significance of hydrogen energy economy, and provides an authoritative and up-to-date scientific account of hydrogen generation, storage, transportation, and safety.

Wave power integration with a renewable hydrogen energy system. Paper no. IGEC-1-085

International Nuclear Information System (INIS)

St. Germain, L.; Wild, P.; Rowe, A.

2005-01-01

In British Columbia, approximately 90% of the electricity generated comes from hydroelectric facilities while another abundant and renewable resource, ocean wave energy, is not being utilized at all. Technologies exist that can capture and convert wave energy but there are few studies examining systemic integration of wave energy devices. This work examines the potential to use wave energy as an input into a hydrogen-based renewable energy system. A model of an oscillating water column (OWC) was developed as a module within TRNSYS where it can be coupled to other existing hydrogen-specific components such as an electrolyser, storage device, and fuel cell. The OWC model accounts for device geometry, dynamics, and generator efficiency. For this particular study, wave profiles generated from hourly average data for a location on the west coast of Vancouver Island are used as a resource input. An analysis of the potential to utilise wave energy is carried out with an emphasis on overall system efficiency and resulting device scaling. The results of the integration of wave energy with other renewable energy inputs into a hydrogen-based system are used to make recommendations regarding technical feasibility of wave power projects on Vancouver Island. (author)

International Conference on Solar Concentrators for the Generation of Electricity or Hydrogen: Book of Abstracts

Energy Technology Data Exchange (ETDEWEB)

McConnell, R.; Symko-Davies, M.; Hayden, H.

2005-05-01

The International Conference on Solar Concentrators for the Generation of Electricity or Hydrogen provides an opportunity to learn about current significant research on solar concentrators for generating electricity or hydrogen. The conference will emphasize in-depth technical discussions of recent achievements in technologies that convert concentrated solar radiation to electricity or hydrogen, with primary emphasis on photovoltaic (PV) technologies. Very high-efficiency solar cells--above 37%--were recently developed, and are now widely used for powering satellites. This development demands that we take a fresh look at the potential of solar concentrators for generating low-cost electricity or hydrogen. Solar electric concentrators could dramatically overtake other PV technologies in the electric utility marketplace because of the low capital cost of concentrator manufacturing facilities and the larger module size of concentrators. Concentrating solar energy also has advantages for th e solar generation of hydrogen. Around the world, researchers and engineers are developing solar concentrator technologies for entry into the electricity generation market and several have explored the use of concentrators for hydrogen production. The last conference on the subject of solar electric concentrators was held in November of 2003 and proved to be an important opportunity for researchers and developers to share new and crucial information that is helping to stimulate projects in their countries.

One Step Hydrogen Generation Through Sorption Enhanced Reforming

Energy Technology Data Exchange (ETDEWEB)

Mays, Jeff [Gas Technology Inst., Des Plaines, IL (United States)

2017-08-03

One-step hydrogen generation, using Sorption Enhanced Reforming (SER) technology, is an innovative means of providing critical energy and environmental improvements to US manufacturing processes. The Gas Technology Institute (GTI) is developing a Compact Hydrogen Generator (CHG) process, based on SER technology, which successfully integrates previously independent process steps, achieves superior energy efficiency by lowering reaction temperatures, and provides pathways to doubling energy productivity with less environmental pollution. GTI’s prior CHG process development efforts have culminated in an operational pilot plant. During the initial pilot testing, GTI identified two operating risks- 1) catalyst coating with calcium aluminate compounds, 2) limited solids handling of the sorbent. Under this contract GTI evaluated alternative materials (one catalyst and two sorbents) to mitigate both risks. The alternate catalyst met performance targets and did not experience coating with calcium aluminate compounds of any kind. The alternate sorbent materials demonstrated viable operation, with one material enabling a three-fold increase in sorbent flow. The testing also demonstrated operation at 90% of its rated capacity. Lastly, a carbon dioxide co-production study was performed to assess the advantage of the solid phase separation of carbon dioxide- inherent in the CHG process. Approximately 70% lower capital cost is achievable compared to SMR-based hydrogen production with CO2 capture, as well as improved operating costs.

Fiscal 1999 hydrogen utilization international clean energy system technology (WE-NET). Phase 2 R and D (Task 1. Survey/study concerning system evaluation); 1999 nendo suiso riyo kokusai clean energy system gijutsu (WE-NET) dainiki kenkyu kaihatsu. Task 1. System hyoka ni kansuru chosa kenkyu

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

With the aim of formulating a strategy for introducing hydrogen, assessment was carried out on the energy consumption, environmental impacts and cost effiectiveness concerning various hydrogen utilization systems. In regard to soda-electrolysis by-product hydrogen and coke-oven by-product hydrogen, hydrogen supply capacity and cost effectiveness were evaluated. As a result, the two systems were found to have an annual hydrogen supply capacity of 11.52 GNm{sup 3} in total. As to the cost effectiveness, transportation by pipeline was 34 yen/Nm{sup 3}-H{sub 2} in the case of soda-electrolysis by-product hydrogen, and 40 yen/Nm{sup 3}-H{sub 2} in the case of coke-oven by-product hydrogen. An estimated cost of power generation showed 56 yen to 67 yen/kWh in such a system on remote islands as replacing diesel power generation by wind power generation, storing part of the electric energy produced in the form of hydrogen through water electrolysis, and using it as fuel for power generation by the fuel cell unit if wind conditions are unfavorable. Power generation cost on remote islands at present is sometimes in excess of 50 yen/kWh; therefore, this combined system showed promising results. The cost of using wooden biomass was estimated to be 51,000 yen/TOE , whose competitiveness is uncertain. (NEDO)

Generation of an electromotive force by hydrogen-to-water oxidation with Pt-coated oxidized titanium foils

Energy Technology Data Exchange (ETDEWEB)

Schierbaum, Klaus; El Achhab, Mhamed [Department of Materials Science, Institute for Experimental Condensed Matter Physics, Heinrich-Heine University, 40225 Duesseldorf, Universitaetsstrasse 1 (Germany)

2011-12-15

We show that chemically induced current densities up to 20 mA cm{sup -2} and an electromotive force (EMF) up to 465 mV are generated during the hydrogen-to-water-oxidation over Pt/TiO{sub 2}/Ti devices. We prepare the samples by plasma electrolytic oxidation (PEO) of titanium foils and deposition of Pt contact paste. This process yields porous structures and, depending on the anodization voltage, Schottky diode-type current-voltage curves of various ideality parameters. Our experiments demonstrate that Pt coated anodized titanium can also be utilized as hydrogen sensor; the system offers a number of advantages such as a wide temperature range of operation from -40 to 80 C, quick response and decay times of signals, and good electrical stability. Idealized sketch of the Pt coated anodized Ti foil and application as hydrogen sensor and electric generator. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Multi-objective technico-economic optimization of energy conversion systems: hydrogen and electricity cogeneration from Generation IV nuclear reactor

International Nuclear Information System (INIS)

Gomez, A.

2008-01-01

With the increase in environmental considerations, such as the control of greenhouse emissions, and with the decrease in the fossil energy resources, hydrogen is currently considered as a promising energy vector. One of the main technological challenges of a future hydrogen economy is its large scale production without fossil fuel emissions. Under this context, nuclear energy is particularly adapted for hydrogen massive production by thermochemical cycles or high temperature electrolysis. One of the selected nuclear systems is the Very High Temperature Reactor (950 C/1200 C), cooled with helium, and dedicated to hydrogen production or to hydrogen electricity cogeneration. The main objective of this investigation, within the framework of a collaboration between CEA, French Atomic Agency (Cadarache) and LGC (Toulouse), consists in defining a technico-economic optimization methodology of electricity-hydrogen cogeneration systems, in order to identify and propose promising development strategies. Among the massive production processes of hydrogen, the thermochemical cycle Iodine-Sulphur has been considered. Taking into account the diversity of the used energies (i.e., heat and electricity) on the one hand and of the produced energies (hydrogen and electricity) on the other hand of the studied cogeneration system, an exergetic approach has been developed due to its ability to consider various energy forms on the same thermodynamical basis. The CYCLOP software tool (CEA) is used for the thermodynamic modelling of these systems. The economic criterion, calculated using the SEMER software tool (CEA), is based on the minimization of the total production site cost over its lifespan i.e., investment, operating costs and nuclear fuel cost. Capital investment involves the development of cost functions adapted to specific technologies and their specific operating conditions. The resulting optimization problems consist in maximizing the energy production, while minimizing the

Integrated Microchannel Reformer/Hydrogen Purifier for Fuel Cell Power Systems, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Makel Engineering, Inc. (MEI) and Colorado School of Mines (CSM) propose to develop an integrated hydrogen generator and purifier system for conversion of in-situ...

Impact of different metal turbidities on radiolytic hydrogen generation in nuclear power plants

International Nuclear Information System (INIS)

Kumbhar, A.G.; Belapurkar, A.D.; Venkateswaran, G.; Kishore, K.

2005-01-01

Radiolytic hydrogen generation on γ irradiation of turbid solutions containing metal turbidities such as titanium, nickel, iron, chromium, copper, indium, and aluminium was studied. It is suggested that the chemical reactivity of the metal in the turbid solution with e aq -/H/OH produced by radiolysis of water interferes with the recombination reactions which destroy H 2 and H 2 O 2 , thus leading to higher yield of hydrogen. The rate of generation of hydrogen and the G(H 2 ) value is related to the reactivity of the metal ion/hydroxylated species with the free radicals. (orig.)

NOBLE METAL CHEMISTRY AND HYDROGEN GENERATION DURING SIMULATED DWPF MELTER FEED PREPARATION

Energy Technology Data Exchange (ETDEWEB)

Koopman, D

2008-06-25

Simulations of the Defense Waste Processing Facility (DWPF) Chemical Processing Cell vessels were performed with the primary purpose of producing melter feeds for the beaded frit program plus obtaining samples of simulated slurries containing high concentrations of noble metals for off-site analytical studies for the hydrogen program. Eight pairs of 22-L simulations were performed of the Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME) cycles. These sixteen simulations did not contain mercury. Six pairs were trimmed with a single noble metal (Ag, Pd, Rh, or Ru). One pair had all four noble metals, and one pair had no noble metals. One supporting 4-L simulation was completed with Ru and Hg. Several other 4-L supporting tests with mercury have not yet been performed. This report covers the calculations performed on SRNL analytical and process data related to the noble metals and hydrogen generation. It was originally envisioned as a supporting document for the off-site analytical studies. Significant new findings were made, and many previous hypotheses and findings were given additional support as summarized below. The timing of hydrogen generation events was reproduced very well within each of the eight pairs of runs, e.g. the onset of hydrogen, peak in hydrogen, etc. occurred at nearly identical times. Peak generation rates and total SRAT masses of CO{sub 2} and oxides of nitrogen were reproduced well. Comparable measures for hydrogen were reproduced with more variability, but still reasonably well. The extent of the reproducibility of the results validates the conclusions that were drawn from the data.

Very High Efficiency Reactor (VHER) Concepts for Electrical Power Generation and Hydrogen Production

International Nuclear Information System (INIS)

PARMA JR, EDWARD J.; PICKARD, PAUL S.; SUO-ANTTILA, AHTI JORMA

2003-01-01

The goal of the Very High Efficiency Reactor study was to develop and analyze concepts for the next generation of nuclear power reactors. The next generation power reactor should be cost effective compared to current power generation plant, passively safe, and proliferation-resistant. High-temperature reactor systems allow higher electrical generating efficiencies and high-temperature process heat applications, such as thermo-chemical hydrogen production. The study focused on three concepts; one using molten salt coolant with a prismatic fuel-element geometry, the other two using high-pressure helium coolant with a prismatic fuel-element geometry and a fuel-pebble element design. Peak operating temperatures, passive-safety, decay heat removal, criticality, burnup, reactivity coefficients, and material issues were analyzed to determine the technical feasibility of each concept

Microelectrode generator-collector systems for electrolytic titration: theoretical and practical considerations.

Science.gov (United States)

Bell, Christopher G; Seelanan, Parinya; O'Hare, Danny

2017-10-23

Electochemical generator-collector systems, where one electrode is used to generate a reagent, have a potentially large field of application in sensing and measurement. We present a new theoretical description for coplanar microelectrode disc-disc systems where the collector is passive (such as a potentiometric sensor) and the generator is operating at constant flux. This solution is then used to develop a leading order solution for such a system where the reagent reacts reversibly in solution, such as in acid-base titration, where a hydrogen ion flux is generated by electrolysis of water. The principal novel result of the theory is that such devices are constrained by a maximum reagent flux. The hydrogen ion concentration at the collector will only reflect the buffer capacity of the bulk solution if this constraint is met. Both mathematical solutions are evaluated with several microfabricated devices and reasonable agreement with theory is demonstrated.

Micro poly(3-sulfopropyl methacrylate) hydrogel synthesis for in situ metal nanoparticle preparation and hydrogen generation from hydrolysis of NaBH4

International Nuclear Information System (INIS)

Turhan, Tugce; Güvenilir, Yuksel Avcıbası; Sahiner, Nurettin

2013-01-01

Polymeric hydrogels derived from SPM (3-sulfopropyl methacrylate) of micrometer size were used in the preparation of a composite-catalyst system for hydrogen generation from hydrolysis of NaBH 4 . In situ Co and Ni nanoparticles were prepared by chemical reduction of absorbed Co (II) and Ni (II) ions inside the hydrogel networks, and the whole composite was used as a catalyst system. The catalytic activity of the metal nanoparticles within the p(SPM) hydrogel matrix was better and faster using Co than with Ni. Additionally, other parameters that affect the hydrogen generation rate, such as temperature, metal reloading, the catalyst amounts as well as reusability, were also investigated. It was found that p(SPM)–Co micro hydrogels were even effective for hydrogen generation at 0 °C with a hydrogen generation rate of 966 (mL H 2 ) (min) −1 (g of Co) −1 . The activation energy, activation enthalpy, and activation entropy for the hydrolysis reaction of NaBH 4 with micro p(SPM)–Co catalyst system were calculated as 44.3 kJ/mol, 43.26 kJ/mol K, and −150.93 J/mol K, respectively. - Highlights: ► Microgel embedding metal catalyst for H 2 production. ► Advanced materials for green energy. ► Soft microgel reactors for H 2 production from NaBH 4 hydrolysis

Hierarchical energy management system for stand-alone hybrid system based on generation costs and cascade control

International Nuclear Information System (INIS)

Torreglosa, J.P.; García, P.; Fernández, L.M.; Jurado, F.

2014-01-01

Highlights: • We present an energy management system for a stand-alone WT/PV/hydrogen/battery hybrid system. • Hierarchical control composed by master and slave control strategies. • Control assures reliable electricity support for stand-alone applications subject to technical and economic criteria. - Abstract: This paper presents an energy management system (EMS) for stand-alone hybrid systems composed by photovoltaic (PV) solar panels and a wind turbine (WT) as primary energy sources and two energy storage systems, which are a hydrogen system and a battery. The hydrogen system is composed of fuel cell (FC), electrolyzer and hydrogen storage tank. The EMS is a hierarchical control composed by a master control strategy and a slave control strategy. On the one hand, the master control generates the reference powers to meet several premises (such as to satisfy the load power demand, and to maintain the hydrogen tank level and the state of charge (SOC) of the battery between their target margins), taking also into account economic aspects to discriminate between using the battery or hydrogen system. On the other hand, the slave control modifies the reference powers generated by the master control according to the energy sources dynamic limitations, and maintains the DC bus voltage at its reference value. The models, implemented in MATLAB-Simulink environment, have been developed from commercially available components. To check the viability of the proposed EMS, two kinds of simulations were carried out: (1) A long-term simulation of 25 years (expected lifetime of the system) with a sample time of one hour to validate the master control of the EMS; and (2) A short-term simulation with sudden net power variations to validate the slave control of the EMS

Utilization of hydrogen gas production for electricity generation in ...

African Journals Online (AJOL)

Utilization of hydrogen gas production for electricity generation in fuel cell by Enterobacter aerogenes ADH 43 with many kinds of carbon sources in batch stirred tank reactor. MA Rachman, LD Eniya, Y Liasari, MM Nasef, A Ahmad, H Saidi ...

Method and system for hydrogen evolution and storage

Science.gov (United States)

Thorn, David L.; Tumas, William; Hay, P. Jeffrey; Schwarz, Daniel E.; Cameron, Thomas M.

2012-12-11

A method and system for storing and evolving hydrogen (H.sub.2) employ chemical compounds that can be hydrogenated to store hydrogen and dehydrogenated to evolve hydrogen. A catalyst lowers the energy required for storing and evolving hydrogen. The method and system can provide hydrogen for devices that consume hydrogen as fuel.

Tool for optimal design and operation of hydrogen storage based autonomous energy systems

Energy Technology Data Exchange (ETDEWEB)

Oberschachtsiek, B.; Lemken, D. [ZBT - Duisburg (Germany); Stark, M.; Krost, G. [Duisburg-Essen Univ. (Germany)

2010-07-01

Decentralized small scale electricity generation based on renewable energy sources usually necessitates decoupling of volatile power generation and consumption by means of energy storage. Hydrogen has proven as an eligible storage medium for mid- and long-term range, which - when indicated - can be reasonably complemented by accumulator short term storage. The selection of appropriate system components - sources, storage devices and the appertaining peripherals - is a demanding task which affords a high degree of freedom but, on the other hand, has to account for various operational dependencies and restrictions of system components, as well as for conduct of load and generation. An innovative tool facilitates the configuration and dimensioning of renewable energy based power supply systems with hydrogen storage paths, and allows for applying appropriate operation strategies. This tool accounts for the characteristics and performances of relevant power sources, loads, and types of energy storage, and also regards safety rules the energy system has to comply with. In particular, the tool is addressing small, detached and autonomous supply systems. (orig.)

Nuclear power reactors and hydrogen storage systems

International Nuclear Information System (INIS)

Ibrahim Aly Mahmoud El Osery.

1980-01-01

Among conclusions and results come by, a nuclear-electric-hydrogen integrated power system was suggested as a way to prevent the energy crisis. It was shown that the hydrogen power system using nuclear power as a leading energy resource would hold an advantage in the current international situation as well as for the long-term future. Results reported provide designers of integrated nuclear-electric-hydrogen systems with computation models and routines which will allow them to explore the optimal solution in coupling power reactors to hydrogen producing systems, taking into account the specific characters of hydrogen storage systems. The models were meant for average computers of a type easily available in developing countries. (author)

A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions.

Science.gov (United States)

Brack, Paul; Dann, Sandie; Wijayantha, K G Upul; Adcock, Paul; Foster, Simon

2016-08-17

There is a growing research interest in the development of portable systems which can deliver hydrogen on-demand to proton exchange membrane (PEM) hydrogen fuel cells. Researchers seeking to develop such systems require a method of measuring the generated hydrogen. Herein, we describe a simple, low-cost, and robust method to measure the hydrogen generated from the reaction of solids with aqueous solutions. The reactions are conducted in a conventional one-necked round-bottomed flask placed in a temperature controlled water bath. The hydrogen generated from the reaction in the flask is channeled through tubing into a water-filled inverted measuring cylinder. The water displaced from the measuring cylinder by the incoming gas is diverted into a beaker on a balance. The balance is connected to a computer, and the change in the mass reading of the balance over time is recorded using data collection and spreadsheet software programs. The data can then be approximately corrected for water vapor using the method described herein, and parameters such as the total hydrogen yield, the hydrogen generation rate, and the induction period can also be deduced. The size of the measuring cylinder and the resolution of the balance can be changed to adapt the setup to different hydrogen volumes and flow rates.

Molecular metal-Oxo catalysts for generating hydrogen from water

Science.gov (United States)

Long, Jeffrey R; Chang, Christopher J; Karunadasa, Hemamala I

2015-02-24

A composition of matter suitable for the generation of hydrogen from water is described, the positively charged cation of the composition having the general formula [(PY5W.sub.2)MO].sup.2+, wherein PY5W.sub.2 is (NC.sub.5XYZ)(NC.sub.5H.sub.4).sub.4C.sub.2W.sub.2, M is a transition metal, and W, X, Y, and Z can be H, R, a halide, CF.sub.3, or SiR.sub.3, where R can be an alkyl or aryl group. The two accompanying counter anions, in one embodiment, can be selected from the following Cl.sup.-, I.sup.-, PF.sub.6.sup.-, and CF.sub.3SO.sub.3.sup.-. In embodiments of the invention, water, such as tap water containing electrolyte or straight sea water can be subject to an electric potential of between 1.0 V and 1.4 V relative to the standard hydrogen electrode, which at pH 7 corresponds to an overpotential of 0.6 to 1.0 V, with the result being, among other things, the generation of hydrogen with an optimal turnover frequency of ca. 1.5 million mol H.sub.2/mol catalyst per h.

A polymer electrolyte fuel cell stack for stationary power generation from hydrogen fuel

Energy Technology Data Exchange (ETDEWEB)

Gottesfeld, S. [Los Alamos National Lab., NM (United States)

1995-09-01

The fuel cell is the most efficient device for the conversion of hydrogen fuel to electric power. As such, the fuel cell represents a key element in efforts to demonstrate and implement hydrogen fuel utilization for electric power generation. The low temperature, polymer electrolyte membrane fuel cell (PEMFC) has recently been identified as an attractive option for stationary power generation, based on the relatively simple and benign materials employed, the zero-emission character of the device, and the expected high power density, high reliability and low cost. However, a PEMFC stack fueled by hydrogen with the combined properties of low cost, high performance and high reliability has not yet been demonstrated. Demonstration of such a stack will remove a significant barrier to implementation of this advanced technology for electric power generation from hydrogen. Work done in the past at LANL on the development of components and materials, particularly on advanced membrane/electrode assemblies (MEAs), has contributed significantly to the capability to demonstrate in the foreseeable future a PEMFC stack with the combined characteristics described above. A joint effort between LANL and an industrial stack manufacturer will result in the demonstration of such a fuel cell stack for stationary power generation. The stack could operate on hydrogen fuel derived from either natural gas or from renewable sources. The technical plan includes collaboration with a stack manufacturer (CRADA). It stresses the special requirements from a PEMFC in stationary power generation, particularly maximization of the energy conversion efficiency, extension of useful life to the 10 hours time scale and tolerance to impurities from the reforming of natural gas.

Nano-design of quantum dot-based photocatalysts for hydrogen generation using advanced surface molecular chemistry

KAUST Repository

Yu, Weili; Noureldine, Dalal; Isimjan, Tayirjan T.; Lin, Bin; Del Gobbo, Silvano; Abulikemu, Mutalifu; Hedhili, Mohamed N.; Anjum, Dalaver H.; Takanabe, Kazuhiro

2015-01-01

Efficient photocatalytic hydrogen generation in a suspension system requires a sophisticated nano-device that combines a photon absorber with effective redox catalysts. This study demonstrates an innovative molecular linking strategy for fabricating photocatalytic materials that allow effective charge separation of excited carriers, followed by efficient hydrogen evolution. The method for the sequential replacement of ligands with appropriate molecules developed in this study tethers both quantum dots (QDs), as photosensitizers, and metal nanoparticles, as hydrogen evolution catalysts, to TiO2 surfaces in a controlled manner at the nano-level. Combining hydrophobic and hydrophilic interactions on the surface, CdSe-ZnS core-shell QDs and an Au-Pt alloy were attached to TiO2 without overlapping during the synthesis. The resultant nano-photocatalysts achieved substantially high-performance visible-light-driven photocatalysis for hydrogen evolution. All syntheses were conducted at room temperature and in ambient air, providing a promising route for fabricating visible-light-responsive photocatalysts.

Commercial Optimization of a 100 kg/day PEM based Hydrogen Generator For Energy and Industrial Applications

International Nuclear Information System (INIS)

Moulthrop, L.; Anderson, E.; Chow, O.; Friedland, R.; Maloney, T.; Schiller, M.

2006-01-01

Commercial hydrogen generators using PEM water electrolysis are well proven, serving industrial applications worldwide in over 50 countries. Now, market and environmental requirements are converging to demand larger on-site hydrogen generators. North American liquid H 2 shortages, increasing trucking costs, developing economies with no liquid infrastructure, utilities, and forklift fuel cell fueling applications are all working to increase market demand for commercial on-site H 2 generation. These commercial applications may be satisfied by a 100 kg H 2 /day module; this platform can be the pathway towards a 500 kg H 2 /day generator desired for small fore-court hydrogen vehicle fueling stations. This paper discusses the steps necessary and activities already underway to develop a 100 to 500 kg H 2 /day PEM hydrogen generator platform to meet commercial market cost targets and approach US DoE transportation fueling cost targets. (authors)

Turning the wind into hydrogen: The long-run impact on electricity prices and generating capacity

International Nuclear Information System (INIS)

Green, Richard; Hu, Helen; Vasilakos, Nicholas

2011-01-01

Hydrogen production via electrolysis has been proposed as a way of absorbing the fluctuating electricity generated by wind power, potentially allowing the use of cheap electricity at times when it would otherwise be in surplus. We show that large-scale adoption of electrolysers would change the shape of the load-duration curve for electricity, affecting the optimal capacity mix. Nuclear power stations will replace gas-fired power stations, as they are able to run for longer periods of time. Changes in the electricity capacity mix will be much greater than changes to the pattern of prices. The long-run supply price of hydrogen will thus tend to be insensitive to the amount produced. - Research Highlights: → Hydrogen production from electrolysis may offset intermittent wind generation. → The generation capacity mix will change in response to changed demand patterns. → The long-run equilibrium supply curve for hydrogen will be quite flat. → The production cost will be very sensitive to fuel prices paid by generators.

Real-time integration of optimal generation scheduling with MPC for the energy management of a renewable hydrogen-based microgrid

International Nuclear Information System (INIS)

Petrollese, Mario; Valverde, Luis; Cocco, Daniele; Cau, Giorgio; Guerra, José

2016-01-01

Highlights: • Energy management strategy for a renewable hydrogen-based microgrid. • Integration of optimal generation scheduling with a model predictive control. • Experimental tests are carried out simulating typical summer and winter days. • Effective improvement in performance and reduction in microgrid operating cost are achieved. - Abstract: This paper presents a novel control strategy for the optimal management of microgrids with high penetration of renewable energy sources and different energy storage systems. The control strategy is based on the integration of optimal generation scheduling with a model predictive control in order to achieve both long and short-term optimal planning. In particular, long-term optimization of the various microgrid components is obtained by the adoption of an optimal generation scheduling, in which a statistical approach is used to take into account weather and load forecasting uncertainties. The real-time management of the microgrid is instead entrusted to a model predictive controller, which has the important feature of using the results obtained by the optimal generation scheduling. The proposed control strategy was tested in a laboratory-scale microgrid present at the University of Seville, which is composed of an electronic power source that emulates a photovoltaic system, a battery bank and a hydrogen production and storage system. Two different experimental tests that simulate a summer and a winter day were carried out over a 24-h period to verify the reliability and performance enhancement of the control system. Results show an effective improvement in performance in terms of reduction of the microgrid operating cost and greater involvement of the hydrogen storage system for the maintenance of a spinning reserve in batteries.

The prospects for hydrogen as an energy carrier: an overview of hydrogen energy and hydrogen energy systems

International Nuclear Information System (INIS)

Rosen, Marc A.; Koohi-Fayegh, Seama

2016-01-01

Hydrogen is expected to play a key role as an energy carrier in future energy systems of the world. As fossil-fuel supplies become scarcer and environmental concerns increase, hydrogen is likely to become an increasingly important chemical energy carrier and eventually may become the principal chemical energy carrier. When most of the world's energy sources become non-fossil based, hydrogen and electricity are expected to be the two dominant energy carriers for the provision of end-use services. In such a ''hydrogen economy,'' the two complementary energy carriers, hydrogen and electricity, are used to satisfy most of the requirements of energy consumers. A transition era will bridge the gap between today's fossil-fuel economy and a hydrogen economy, in which non-fossil-derived hydrogen will be used to extend the lifetime of the world's fossil fuels - by upgrading heavy oils, for instance - and the infrastructure needed to support a hydrogen economy is gradually developed. In this paper, the role of hydrogen as an energy carrier and hydrogen energy systems' technologies and their economics are described. Also, the social and political implications of hydrogen energy are examined, and the questions of when and where hydrogen is likely to become important are addressed. Examples are provided to illustrate key points. (orig.)

Standard-D hydrogen monitoring system, system design description

International Nuclear Information System (INIS)

Schneider, T.C.

1996-01-01

During most of the year, it is assumed that the vapor space in the 177 radioactive waste tanks on the Hanford Project site contain a uniform mixture of gases. Several of these waste tanks (currently twenty-five, 6 Double Shell Tanks and 19 Single Shell Tanks) were identified as having the potential for the buildup of gasses to a flammable level. An active ventilation system in the Double Shell Tanks and a passive ventilation system in the Single Shell Tanks provides a method of expelling gasses from the tanks. A gas release from a tank causes a temporary rise in the tank pressure, and a potential for increased concentration of hydrogen gas in the vapor space. The gas is released via the ventilation systems until a uniform gas mixture in the vapor space is once again achieved. The Standard Hydrogen Monitoring System (SHMS) is designed to monitor and quantify the percent hydrogen concentration during these potential gas releases. This document describes the design of the Standard-D Hydrogen Monitoring System, (SHMS-D) and its components as it differs from the original SHMS

Cuboid Ni2 P as a Bifunctional Catalyst for Efficient Hydrogen Generation from Hydrolysis of Ammonia Borane and Electrocatalytic Hydrogen Evolution.

Science.gov (United States)

Du, Yeshuang; Liu, Chao; Cheng, Gongzhen; Luo, Wei

2017-11-16

The design of high-performance catalysts for hydrogen generation is highly desirable for the upcoming hydrogen economy. Herein, we report the colloidal synthesis of nanocuboid Ni 2 P by the thermal decomposition of nickel chloride hexahydrate (NiCl 2 ⋅6 H 2 O) and trioctylphosphine. The obtained nanocuboid Ni 2 P was characterized by using powder X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and inductively coupled plasma atomic emission spectroscopy. For the first time, the as-synthesized nanocuboid Ni 2 P is used as a bifunctional catalyst for hydrogen generation from the hydrolysis of ammonia borane and electrocatalytic hydrogen evolution. Owing to the strong synergistic electronic effect between Ni and P, the as-synthesized Ni 2 P exhibits catalytic performance that is superior to its counterpart without P doping. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hydrogen-control systems for severe LWR accident conditions - a state-of-technology report

International Nuclear Information System (INIS)

Hilliard, R.K.; Postma, A.K.; Jeppson, D.W.

1983-03-01

This report reviews the current state of technology regarding hydrogen safety issues in light water reactor plants. Topics considered in this report relate to control systems and include combustion prevention, controlled combustion, minimization of combustion effects, combination of control concepts, and post-accident disposal. A companion report addresses hydrogen generation, distribution, and combustion. The objectives of the study were to identify the key safety issues related to hydrogen produced under severe accident conditions, to describe the state of technology for each issue, and to point out ongoing programs aimed at resolving the open issues

A study of wind hydrogen production of systems for Malaysia

International Nuclear Information System (INIS)

Ibrahim, M.Z.; Kamaruzzaman Sopian; Wan Ramli Wan Daud; Othman, M.Y.; Baharuddin Yatim; Veziroglu, T.N.

2006-01-01

Recently, Malaysia is looking into the potential of using hydrogen as future fuel. By recognizing the potential of hydrogen fuel, the government had channeled a big amount of money in funds to related organizations to embark on hydrogen research and development programmed. The availability of indigenous renewable resources, high trade opportunities, excellent research capabilities and current progress in hydrogen research at the university are some major advantages for the country to attract government and industry investment in hydrogen. It is envisaged that overall energy demand in Malaysia as stated in the Eighth Malaysia Plan (EMP) report will increase by about 7.8 percent per annum in this decade at the present economic growth. Considering the vast potential inherent in renewable energy (RE), it could be a significant contributor to the national energy supply. Malaysia had been blessed with abundant and varied resources of energy, nevertheless, concerted efforts should be undertaken to ensure that the development of energy resources would continue to contribute to the nation's economic expansion. In this regard, an initial study has been carried out to see the available potential of wind energy towards the hydrogen production, that could be utilized in various applications particularly in Malaysian climate condition via a computer simulation (HYDROGEMS), which built for TRNSYS (a transient system simulation program) version 15. The system simulated in this study consist of one unit (1 kW) wind turbine, an electrolyze (1 kW), a hydrogen (H 2 ) storage tank, and a power conditioning system. A month hourly data of highest wind speed is obtained from the local weather station that is at Kuala Terengganu Air Port located at 5''o 23'' latitude (N) and 103''o 06'' Longitude (E). The results show, wind energy in Malaysian Climate has a potential to generate hydrogen with the minimum rate approximately 9 m 3 /hr and storage capacity of 60 Nm 3 , State of Charge (SOC

Sizing and economic analysis of stand alone photovoltaic system with hydrogen storage

Science.gov (United States)

Nordin, N. D.; Rahman, H. A.

2017-11-01

This paper proposes a design steps in sizing of standalone photovoltaic system with hydrogen storage using intuitive method. The main advantage of this method is it uses a direct mathematical approach to find system’s size based on daily load consumption and average irradiation data. The keys of system design are to satisfy a pre-determined load requirement and maintain hydrogen storage’s state of charge during low solar irradiation period. To test the effectiveness of the proposed method, a case study is conducted using Kuala Lumpur’s generated meteorological data and rural area’s typical daily load profile of 2.215 kWh. In addition, an economic analysis is performed to appraise the proposed system feasibility. The finding shows that the levelized cost of energy for proposed system is RM 1.98 kWh. However, based on sizing results obtained using a published method with AGM battery as back-up supply, the system cost is lower and more economically viable. The feasibility of PV system with hydrogen storage can be improved if the efficiency of hydrogen storage technologies significantly increases in the future. Hence, a sensitivity analysis is performed to verify the effect of electrolyzer and fuel cell efficiencies towards levelized cost of energy. Efficiencies of electrolyzer and fuel cell available in current market are validated using laboratory’s experimental data. This finding is needed to envisage the applicability of photovoltaic system with hydrogen storage as a future power supply source in Malaysia.

Hydrogen Village : creating hydrogen and fuel cell communities

International Nuclear Information System (INIS)

Smith, G.R.

2009-01-01

The Hydrogen Village (H2V) is a collaborative public-private partnership administered through Hydrogen and Fuel Cells Canada and funded by the Governments of Canada and Ontario. This end user-driven, market development program accelerates the commercialization of hydrogen and fuel cell (FC) technologies throughout the Greater Toronto Area (GTA). The program targets 3 specific aspects of market development, notably deployment of near market technologies in community based stationary and mobile applications; development of a coordinated hydrogen delivery and equipment service infrastructure; and societal factors involving corporate policy and public education. This presentation focused on lessons learned through outreach programs and the deployment of solid oxide fuel cell (SOFC) heat and power generation; indoor and outdoor fuel cell back up power systems; fuel cell-powered forklifts, delivery vehicles, and utility vehicles; hydrogen internal combustion engine powered shuttle buses, sedans, parade float; hydrogen production/refueling stations in the downtown core; and temporary fuel cell power systems

Designing Microporus Carbons for Hydrogen Storage Systems

Energy Technology Data Exchange (ETDEWEB)

Alan C. Cooper

2012-05-02

An efficient, cost-effective hydrogen storage system is a key enabling technology for the widespread introduction of hydrogen fuel cells to the domestic marketplace. Air Products, an industry leader in hydrogen energy products and systems, recognized this need and responded to the DOE 'Grand Challenge' solicitation (DOE Solicitation DE-PS36-03GO93013) under Category 1 as an industry partner and steering committee member with the National Renewable Energy Laboratory (NREL) in their proposal for a center-of-excellence on Carbon-Based Hydrogen Storage Materials. This center was later renamed the Hydrogen Sorption Center of Excellence (HSCoE). Our proposal, entitled 'Designing Microporous Carbons for Hydrogen Storage Systems,' envisioned a highly synergistic 5-year program with NREL and other national laboratory and university partners.

Hybrid vehicle system studies and optimized hydrogen engine design

Science.gov (United States)

Smith, J. R.; Aceves, S.

1995-04-01

We have done system studies of series hydrogen hybrid automobiles that approach the PNGV design goal of 34 km/liter (80 mpg), for 384 km (240 mi) and 608 km (380 mi) ranges. Our results indicate that such a vehicle appears feasible using an optimized hydrogen engine. We have evaluated the impact of various on-board storage options on fuel economy. Experiments in an available engine at the Sandia CRF demonstrated NO(x) emissions of 10 to 20 ppM at an equivalence ratio of 0.4, rising to about 500 ppm at 0.5 equivalence ratio using neat hydrogen. Hybrid simulation studies indicate that exhaust NO(x) concentrations must be less than 180 ppM to meet the 0.2 g/mile ULEV or Federal Tier II emissions regulations. LLNL has designed and fabricated a first generation optimized hydrogen engine head for use on an existing Onan engine. This head features 15:1 compression ratio, dual ignition, water cooling, two valves and open quiescent combustion chamber to minimize heat transfer losses. Initial testing shows promise of achieving an indicated efficiency of nearly 50% and emissions of less than 100 ppM NO(x). Hydrocarbons and CO are to be measured, but are expected to be very low since their only source is engine lubricating oil. A successful friction reduction program on the Onan engine should result in a brake thermal efficiency of about 42% compared to today's gasoline engines of 32%. Based on system studies requirements, the next generation engine will be about 2 liter displacement and is projected to achieve 46% brake thermal efficiency with outputs of 15 kW for cruise and 40 kW for hill climb.

The prospects for hydrogen as an energy carrier: an overview of hydrogen energy and hydrogen energy systems

Energy Technology Data Exchange (ETDEWEB)

Rosen, Marc A.; Koohi-Fayegh, Seama [Ontario Univ., Oshawa, ON (Canada). Inst. of Technology

2016-02-15

Hydrogen is expected to play a key role as an energy carrier in future energy systems of the world. As fossil-fuel supplies become scarcer and environmental concerns increase, hydrogen is likely to become an increasingly important chemical energy carrier and eventually may become the principal chemical energy carrier. When most of the world's energy sources become non-fossil based, hydrogen and electricity are expected to be the two dominant energy carriers for the provision of end-use services. In such a ''hydrogen economy,'' the two complementary energy carriers, hydrogen and electricity, are used to satisfy most of the requirements of energy consumers. A transition era will bridge the gap between today's fossil-fuel economy and a hydrogen economy, in which non-fossil-derived hydrogen will be used to extend the lifetime of the world's fossil fuels - by upgrading heavy oils, for instance - and the infrastructure needed to support a hydrogen economy is gradually developed. In this paper, the role of hydrogen as an energy carrier and hydrogen energy systems' technologies and their economics are described. Also, the social and political implications of hydrogen energy are examined, and the questions of when and where hydrogen is likely to become important are addressed. Examples are provided to illustrate key points. (orig.)

Development of a Novel Efficient Solid-Oxide Hybrid for Co-generation of Hydrogen and Electricity Using Nearby Resources for Local Application

Energy Technology Data Exchange (ETDEWEB)

Tao, Greg, G.; Virkar, Anil, V.; Bandopadhyay, Sukumar; Thangamani, Nithyanantham; Anderson, Harlan, U.; Brow, Richard, K.

2009-06-30

Developing safe, reliable, cost-effective, and efficient hydrogen-electricity co-generation systems is an important step in the quest for national energy security and minimized reliance on foreign oil. This project aimed to, through materials research, develop a cost-effective advanced technology cogenerating hydrogen and electricity directly from distributed natural gas and/or coal-derived fuels. This advanced technology was built upon a novel hybrid module composed of solid-oxide fuel-assisted electrolysis cells (SOFECs) and solid-oxide fuel cells (SOFCs), both of which were in planar, anode-supported designs. A SOFEC is an electrochemical device, in which an oxidizable fuel and steam are fed to the anode and cathode, respectively. Steam on the cathode is split into oxygen ions that are transported through an oxygen ion-conducting electrolyte (i.e. YSZ) to oxidize the anode fuel. The dissociated hydrogen and residual steam are exhausted from the SOFEC cathode and then separated by condensation of the steam to produce pure hydrogen. The rationale was that in such an approach fuel provides a chemical potential replacing the external power conventionally used to drive electrolysis cells (i.e. solid oxide electrolysis cells). A SOFC is similar to the SOFEC by replacing cathode steam with air for power generation. To fulfill the cogeneration objective, a hybrid module comprising reversible SOFEC stacks and SOFC stacks was designed that planar SOFECs and SOFCs were manifolded in such a way that the anodes of both the SOFCs and the SOFECs were fed the same fuel, (i.e. natural gas or coal-derived fuel). Hydrogen was produced by SOFECs and electricity was generated by SOFCs within the same hybrid system. A stand-alone 5 kW system comprising three SOFEC-SOFC hybrid modules and three dedicated SOFC stacks, balance-of-plant components (including a tailgas-fired steam generator and tailgas-fired process heaters), and electronic controls was designed, though an overall

The car on hydrogen: problems and solutions

International Nuclear Information System (INIS)

Koroteev, A.S.; Smolyarov, V.A.

2004-01-01

Development of the hydrogen power for transformation of the most power-consumption branch of the industry and transport into new power source - hydrogen as strategy direction for the reduction of pollution of environment and deficit of oil motor fuel is considered. On the basis of comparison of different type of electrochemical generators conclusion on advantages of electrochemical generator with solid polymer membrane was made. Different systems of hydrogen storage in automobile are considered. The system of the gaseous hydrogen storage at high pressure in cistern from composite materials is the most promise [ru

Sensitivity to temperature of nuclear energy generation by hydrogen burning

International Nuclear Information System (INIS)

Mitalas, R.

1981-01-01

The sensitivity to temperature of nuclear energy generation by hydrogen burning is discussed. The complexity of the sensitivity is due to the different equilibration time-scales of the constituents of the p-p chain and CN cycle and the dependence of their abundances and time-scales on temperature. The time-scale of the temperature perturbation, compared to the equilibrium time-scale of a constituent, determines whether the constituent is in equilibrium and affects the sensitivity. The temperature sensitivity of the p-p chain for different values of hydrogen abundance, when different constituents come into equilibrium is presented, as well as its variation with 3 He abundance. The temperature sensitivity is drastically different from n 11 , the temperature sensitivity of the proton-proton reaction, unless the time-scale of temperature perturbation is long enough for 3 He to remain in equilibrium. Even in this case the sensitivity of the p-p chain differs significantly from n 11 , unless the temperature is so low that PP II and PP III chains can be neglected. The variation of the sensitivity of CN energy generation is small for different time-scales of temperature variation, because the temperature sensitivities of individual reactions are so similar. The combined sensitivity to temperature of energy generation by hydrogen burning is presented and shown to have a maximum of 16.4 at T 6 = 24.5. For T 6 > 25 the temperature sensitivity is given by the sensitivity of 14 N + p reaction. (author)

Analysis of silicon-based integrated photovoltaic-electrochemical hydrogen generation system under varying temperature and illumination

Institute of Scientific and Technical Information of China (English)

Vishwa Bhatt; Brijesh Tripathi; Pankaj Yadav; Manoj Kumar

2017-01-01

Last decade witnessed tremendous research and development in the area of photo-electrolytic hydrogen generation using chemically stable nanostructured photo-cathode/anode materials.Due to intimately coupled charge separation and photo-catalytic processes,it is very difficult to optimize individual components of such system leading to a very low demonstrated solar-to-fuel efficiency (SFE) of less than 1％.Recently there has been growing interest in an integrated photovoltaic-electrochemical (PV-EC) system based on GaAs solar cells with the demonstrated SFE of 24.5％ under concentrated illumination condition.But a high cost of GaAs based solar cells and recent price drop of poly-crystalline silicon (pc-Si) solar cells motivated researchers to explore silicon based integrated PV-EC system.In this paper a theoretical framework is introduced to model silicon-based integrated PV-EC device.The theoretical framework is used to analyze the coupling and kinetic losses of a silicon solar cell based integrated PV-EC water splitting system under varying temperature and illumination.The kinetic loss occurs in the range of 19.1％-27.9％ and coupling loss takes place in the range of 5.45％-6.74％ with respect to varying illumination in the range of 20-100 mW/cm2.Similarly,the effect of varying temperature has severe impact on the performance of the system,wherein the coupling loss occurs in the range of 0.84％-21.51％ for the temperature variation from 25 to 50 ℃.

Nuclear processes in deuterium/natural hydrogen-metal systems

International Nuclear Information System (INIS)

Zelensky, V.F.

2013-01-01

The survey presents the analysis of the phenomena taking place in deuterium - metal and natural hydrogen - metal systems under cold fusion experimental conditions. The cold fusion experiments have shown that the generation of heat and helium in the deuterium-metal system without emission of energetic gamma-quanta is the result of occurrence of a chain of chemical, physical and nuclear processes observed in the system, culminating in both the fusion of deuterium nuclei and the formation of a virtual, electron-modified excited 4He nucleus. The excitation energy of the helium nucleus is transferred to the matrix through emission of conversion electrons, and that, under appropriate conditions, provides a persistent synthesis of deuterium. The processes occurring in the deuterium/natural hydrogen - metal systems have come to be known as chemonuclear DD- and HD-fusion. The mechanism of stimulation of weak interaction reactions under chemonuclear deuterium fusion conditions by means of strong interaction reactions has been proposed. The results of numerous experiments discussed in the survey bear witness to the validity of chemonuclear fusion. From the facts discussed it is concluded that the chemonuclear deuterium fusion scenario as presented in this paper may serve as a basis for expansion of deeper research and development of this ecologically clean energy source. It is shown that the natural hydrogen-based system, containing 0.015% of deuterium, also has good prospects as an energy source. The chemonuclear fusion processes do not require going beyond the scope of traditional physics for their explanation

Hydrogen Generation by Koh-Ethanol Plasma Electrolysis Using Double Compartement Reactor

Science.gov (United States)

Saksono, Nelson; Sasiang, Johannes; Dewi Rosalina, Chandra; Budikania, Trisutanti

2018-03-01

This study has successfully investigated the generation of hydrogen using double compartment reactor with plasma electrolysis process. Double compartment reactor is designed to achieve high discharged voltage, high concentration, and also reduce the energy consumption. The experimental results showed the use of double compartment reactor increased the productivity ratio 90 times higher compared to Faraday electrolysis process. The highest hydrogen production obtained is 26.50 mmol/min while the energy consumption can reach up 1.71 kJ/mmol H2 at 0.01 M KOH solution. It was shown that KOH concentration, addition of ethanol, cathode depth, and temperature have important effects on hydrogen production, energy consumption, and process efficiency.

Hydrogen sensor

Science.gov (United States)

Duan, Yixiang; Jia, Quanxi; Cao, Wenqing

2010-11-23

A hydrogen sensor for detecting/quantitating hydrogen and hydrogen isotopes includes a sampling line and a microplasma generator that excites hydrogen from a gas sample and produces light emission from excited hydrogen. A power supply provides power to the microplasma generator, and a spectrometer generates an emission spectrum from the light emission. A programmable computer is adapted for determining whether or not the gas sample includes hydrogen, and for quantitating the amount of hydrogen and/or hydrogen isotopes are present in the gas sample.

Identification of intrinsic catalytic activity for electrochemical reduction of water molecules to generate hydrogen

KAUST Repository

Shinagawa, Tatsuya; Takanabe, Kazuhiro

2015-01-01

Insufficient hydronium ion activities at near-neutral pH and under unbuffered conditions induce diffusion-limited currents for hydrogen evolution, followed by a reaction with water molecules to generate hydrogen at elevated potentials. The observed

Prediction of the amount of hydrogen generated during a molten fuel-coolant interaction

International Nuclear Information System (INIS)

Matthern, G.E.; Neuman, J.E.; Madsen, W.W.; Close, J.A.

1990-01-01

The model in development predicts the production of hydrogen as a result of a molten fuel-coolant interaction in a water-cooled nuclear reactor. It has three interrelated modules: kinetics, heat transfer, and hydrodynamics. Second and third order rates are assumed for uranium and aluminum respectively, the chosen fuel and cladding. Heat is generated by chemical reaction and radioactive decay and dissipated through radiation and convection. Dispersion of the melt as it descends through a pool of water is modeled using the Weber number, which ratios the shear forces due to the relative velocities of the fluid and the metal to the surface tension of the metal. Hydrogen generation is sensitive to the initial melt temperature and to the assumptions made about the modes of heat transfer, but not the the impact velocity of the metal particle. The hydrogen generation per unit mass of uranium generally increases as the initial particle size decreases suggesting that the kinetics rather than the heat transfer controls the energy balance

Oxygen transport membrane reactor based method and system for generating electric power

Science.gov (United States)

Kelly, Sean M.; Chakravarti, Shrikar; Li, Juan

2017-02-07

A carbon capture enabled system and method for generating electric power and/or fuel from methane containing sources using oxygen transport membranes by first converting the methane containing feed gas into a high pressure synthesis gas. Then, in one configuration the synthesis gas is combusted in oxy-combustion mode in oxygen transport membranes based boiler reactor operating at a pressure at least twice that of ambient pressure and the heat generated heats steam in thermally coupled steam generation tubes within the boiler reactor; the steam is expanded in steam turbine to generate power; and the carbon dioxide rich effluent leaving the boiler reactor is processed to isolate carbon. In another configuration the synthesis gas is further treated in a gas conditioning system configured for carbon capture in a pre-combustion mode using water gas shift reactors and acid gas removal units to produce hydrogen or hydrogen-rich fuel gas that fuels an integrated gas turbine and steam turbine system to generate power. The disclosed method and system can also be adapted to integrate with coal gasification systems to produce power from both coal and methane containing sources with greater than 90% carbon isolation.

Mixing of radiolytic hydrogen generated within a containment compartment following a LOCA

International Nuclear Information System (INIS)

Willcutt, G.J.E. Jr.; Gido, R.G.

1978-07-01

The objective of this work was to determine hydrogen concentration variations with position and time in a closed containment compartment with radiolytic hydrogen generation in the water on the compartment floor following a Loss-of-Coolant-Accident (LOCA). One application is to determine the potential difference between the compartment maximum hydrogen concentration and a hydrogen detector reading, due to the detector location. Three possible mechanisms for hydrogen transport in the compartment were investigated: (1) molecular diffusion, (2) possible bubble formation and motion, and (3) natural convection flows. A base case cubic compartment with 6.55-m (21.5-ft) height was analyzed. Parameter studies were used to determine the sensitivity of results to compartment size, hydrogen generation rates, diffusion coefficients, and the temperature difference between the floor and the ceiling and walls of the compartment. Diffusion modeling indicates that if no other mixing mechanism is present for the base case, the maximum hydrogen volume percent (vol percent) concentration difference between the compartment floor and ceiling will be 4.8 percent. It will be 24.5 days before the maximum concentration difference is less than 0.5 percent. Bubbles do not appear to be a potential source of hydrogen pocketing in a containment compartment. Compartment natural convection circulation rates for a 2.8 K (5 0 F) temperature difference between the floor and the ceiling and walls are estimated to be at least the equivalent of 1 compartment volume per hour and probably in the range of 4 to 9 compartment volumes per hour. Related natural convection studies indicate there will be turbulent mixing in the compartment for a 2.8 K (5 0 F) temperature difference between the floor and the ceiling and walls

Hydrogen and acoustic detection in steam generators of Super Phenix power plant

International Nuclear Information System (INIS)

Kong, N.; Le Bris, A.; Berthier, P.

1986-05-01

During the isothermal tests of Super-Phenix, two types of measurements were made on the steam generators with regard to the detection of water leaks into the sodium: - the first measurements enabled us to determine the characteristics (sensitivity, response time) of the hydrogen detectors that are already operational for the filling with water and the power operation of the steam generators. They also provided the basis for developing a prototype system for detecting very small water leaks (microleak phase). The other measurements concern the qualification tests of acoustic detectors which have been fitted for the first time to a major industrial installation. The results obtained are very satisfactory but final validation of the acoustic method will only occur after the full-power tests [fr

Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation Project

Energy Technology Data Exchange (ETDEWEB)

Stottler, Gary

2012-02-08

General Motors, LLC and energy partner Shell Hydrogen, LLC, deployed a system of hydrogen fuel cell electric vehicles integrated with a hydrogen fueling station infrastructure to operate under real world conditions as part of the U.S. Department of Energy's Controlled Hydrogen Fleet and Infrastructure Validation and Demonstration Project. This technical report documents the performance and describes the learnings from progressive generations of vehicle fuel cell system technology and multiple approaches to hydrogen generation and delivery for vehicle fueling.

The Italian hydrogen programme

International Nuclear Information System (INIS)

Raffaele Vellone

2001-01-01

Hydrogen could become an important option in the new millennium. It provides the potential for a sustainable energy system as it can be used to meet most energy needs without harming the environment. In fact, hydrogen has the potential for contributing to the reduction of climate-changing emissions and other air pollutants as it exhibits clean combustion with no carbon or sulphur oxide emissions and very low nitrogen oxide emissions. Furthermore, it is capable of direct conversion to electricity in systems such as fuel cells without generating pollution. However, widespread use of hydrogen is not feasible today because of economic and technological barriers. In Italy, there is an ongoing national programme to facilitate the introduction of hydrogen as an energy carrier. This programme aims to promote, in an organic frame, a series of actions regarding the whole hydrogen cycle. It foresees the development of technologies in the areas of production, storage, transport and utilisation. Research addresses the development of technologies for separation and sequestration of CO 2 , The programme is shared by public organisations (research institutions and universities) and national industry (oil companies, electric and gas utilities and research institutions). Hydrogen can be used as a fuel, with significant advantages, both for electric energy generation/ co-generation (thermo-dynamic cycles and fuel cells) and transportation (internal combustion engine and fuel cells). One focus of research will be the development of fuel cell technologies. Fuel cells possess all necessary characteristics to be a key technology in a future economy based on hydrogen. During the initial phase of the project, hydrogen will be derived from fossil sources (natural gas), and in the second phase it will be generated from renewable electricity or nuclear energy. The presentation will provide a review of the hydrogen programme and highlight future goals. (author)

The equilibrium hydrogen pressure-temperature diagram for the liquid sodium-hydrogen-oxygen system

International Nuclear Information System (INIS)

Knights, C.F.; Whittingham, A.C.

1982-01-01

The underlying equilibria in the sodium-hydrogen-oxygen system are presented in the form of a completmentary hydrogen equilibrium pressure-temperature diagram, constructed by using published data and supplemented by experimental measurements of hydrogen equilibrium pressures over condensed phases in the system. Possible applications of the equilibrium pressure-temperature phase diagram limitations regarding its use are outlined

Study on system layout and component design in the HTTR hydrogen production system. Contract research

Energy Technology Data Exchange (ETDEWEB)

Nishihara, Tetsuo; Shimizu, Akira [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Tanihira, Masanori [Mitsubishi Heavy Industries Ltd., Tokyo (Japan); Uchida, Shoji [Advanced Reactor Technology Co., Ltd., Tokyo (Japan)

2003-01-01

The global warming becomes a significant issue in the world so that it needs to reduce the CO{sub 2} emission. It is expected that hydrogen is in place of the fossil fuels such as coal and oil, and plays the important role to resolve the global warming. There are several hydrogen making processes such as water electrolysis and steam reforming of hydrocarbon. Steam reforming of hydrocarbon is a major hydrogen making process because of economy in industry. It utilizes the fossil fuels as process heat for chemical reaction and results in a large CO{sub 2} emission. New steam reforming system without fossil fuel can contribute to resolve the global warming. High temperature gas-cooled reactor (HTGR) has a unique feature to be able to supply a hot helium gas whose temperature is approximately 950degC at the reactor outlet. This makes HTGR possible to utilize for not only power generation but also process heat utilization. JAERI constructed the high temperature engineering test reactor (HTTR) that is a sort of HTGR in Oarai establishment and starts operation. Nuclear heat utilization is one of the R and D items of the HTTR. The steam reforming system coupling to the HTTR for hydrogen production has been designed. This report represents the system layout and design specification of key components in HTTR steam reforming system. (author)

Study on system layout and component design in the HTTR hydrogen production system. Contract research

International Nuclear Information System (INIS)

Nishihara, Tetsuo; Shimizu, Akira; Uchida, Shoji

2003-01-01

The global warming becomes a significant issue in the world so that it needs to reduce the CO 2 emission. It is expected that hydrogen is in place of the fossil fuels such as coal and oil, and plays the important role to resolve the global warming. There are several hydrogen making processes such as water electrolysis and steam reforming of hydrocarbon. Steam reforming of hydrocarbon is a major hydrogen making process because of economy in industry. It utilizes the fossil fuels as process heat for chemical reaction and results in a large CO 2 emission. New steam reforming system without fossil fuel can contribute to resolve the global warming. High temperature gas-cooled reactor (HTGR) has a unique feature to be able to supply a hot helium gas whose temperature is approximately 950degC at the reactor outlet. This makes HTGR possible to utilize for not only power generation but also process heat utilization. JAERI constructed the high temperature engineering test reactor (HTTR) that is a sort of HTGR in Oarai establishment and starts operation. Nuclear heat utilization is one of the R and D items of the HTTR. The steam reforming system coupling to the HTTR for hydrogen production has been designed. This report represents the system layout and design specification of key components in HTTR steam reforming system. (author)

Formic Acid Free Flowsheet Development To Eliminate Catalytic Hydrogen Generation In The Defense Waste Processing

Energy Technology Data Exchange (ETDEWEB)

Lambert, Dan P.; Stone, Michael E.; Newell, J. David; Fellinger, Terri L.; Bricker, Jonathan M.

2012-09-14

The Defense Waste Processing Facility (DWPF) processes legacy nuclear waste generated at the Savannah River Site (SRS) during production of plutonium and tritium demanded by the Cold War. The nuclear waste is first treated via a complex sequence of controlled chemical reactions and then vitrified into a borosilicate glass form and poured into stainless steel canisters. Converting the nuclear waste into borosilicate glass canisters is a safe, effective way to reduce the volume of the waste and stabilize the radionuclides. Testing was initiated to determine whether the elimination of formic acid from the DWPF's chemical processing flowsheet would eliminate catalytic hydrogen generation. Historically, hydrogen is generated in chemical processing of alkaline High Level Waste sludge in DWPF. In current processing, sludge is combined with nitric and formic acid to neutralize the waste, reduce mercury and manganese, destroy nitrite, and modify (thin) the slurry rheology. The noble metal catalyzed formic acid decomposition produces hydrogen and carbon dioxide. Elimination of formic acid by replacement with glycolic acid has the potential to eliminate the production of catalytic hydrogen. Flowsheet testing was performed to develop the nitric-glycolic acid flowsheet as an alternative to the nitric-formic flowsheet currently being processed at the DWPF. This new flowsheet has shown that mercury can be reduced and removed by steam stripping in DWPF with no catalytic hydrogen generation. All processing objectives were also met, including greatly reducing the Slurry Mix Evaporator (SME) product yield stress as compared to the baseline nitric/formic flowsheet. Ten DWPF tests were performed with nonradioactive simulants designed to cover a broad compositional range. No hydrogen was generated in testing without formic acid.

Room temperature hydrogen generation from hydrolysis of ammonia-borane over an efficient NiAgPd/C catalyst

KAUST Repository

Hu, Lei

2014-12-01

NiAgPd nanoparticles are successfully synthesized by in-situ reduction of Ni, Ag and Pd salts on the surface of carbon. Their catalytic activity was examined in ammonia borane (NH3BH3) hydrolysis to generate hydrogen gas. This nanomaterial exhibits a higher catalytic activity than those of monometallic and bimetallic counterparts and a stoichiometric amount of hydrogen was produced at a high generation rate. Hydrogen production rates were investigated in different concentrations of NH3BH3 solutions, including in the borates saturated solution, showing little influence of the concentrations on the reaction rates. The hydrogen production rate can reach 3.6-3.8 mol H2 molcat -1 min-1 at room temperature (21 °C). The activation energy and TOF value are 38.36 kJ/mol and 93.8 mol H2 molcat -1 min-1, respectively, comparable to those of Pt based catalysts. This nanomaterial catalyst also exhibits excellent chemical stability, and no significant morphology change was observed from TEM after the reaction. Using this catalyst for continuously hydrogen generation, the hydrogen production rate can be kept after generating 6.2 L hydrogen with over 10,000 turnovers and a TOF value of 90.3 mol H2 molcat -1 min-1.

Hydrogen generation from formic acid catalyzed by a metal complex under amine-free and aqueous conditions

KAUST Repository

Huang, Kuo-Wei

2018-01-04

The present invention provides a class of catalyst compounds that can safely and effectively release hydrogen gas from a chemical substrate without producing either noxious byproducts or byproducts that will deactivate the catalyst. The present invention provides catalysts used to produce hydrogen that has a satisfactory and sufficient lifespan (measured by turnover number (TON)), that has stability in the presence of moisture, air, acid, or impurities, promote a rapid reaction rate, and remain stable under the reaction conditions required for an effective hydrogen production system. Described herein are compounds for use as catalysts, as well as methods for producing hydrogen from formic acid and/or a formate using the disclosed catalysts. The methods include contacting formic acid and/or a formate with a catalyst as described herein, as well as methods of producing formic acid and/or a formate using the disclosed catalyst and methods for generating electricity using the catalysts described herein.

Lattice-enabled nuclear reactions in the nickel and hydrogen gas system

International Nuclear Information System (INIS)

Nagel, David J.

2015-01-01

Thousands of lattice-enabled nuclear reaction (LENR) experiments involving electrochemical loading of deuterium into palladium have been conducted and reported in hundreds of papers. But, it appears that the first commercial LENR power generators will employ gas loading of hydrogen onto nickel. This article reviews the scientific base for LENR in the gas-loaded Ni-H system, and some of the tests of pre-commercial prototype generators based on this combination. (author)

Photocatalytic hydrogen generation from water under visible light using core/shell nano-catalysts.

Science.gov (United States)

Wang, X; Shih, K; Li, X Y

2010-01-01

A microemulsion technique was employed to synthesize nano-sized photocatalysts with a core (CdS)/shell (ZnS) structure. The primary particles of the photocatalysts were around 10 nm, and the mean size of the catalyst clusters in water was about 100 nm. The band gaps of the catalysts ranged from 2.25 to 2.46 eV. The experiments of photocatalytic H(2) generation showed that the catalysts (CdS)(x)/(ZnS)(1-x) with x ranging from 0.1 to 1 were able to produce hydrogen from water photolysis under visible light. The catalyst with x=0.9 had the highest rate of hydrogen production. The catalyst loading density also influenced the photo-hydrogen production rate, and the best catalyst concentration in water was 1 g L(-1). The stability of the nano-catalysts in terms of size, morphology and activity was satisfactory during an extended test period for a specific hydrogen production rate of 2.38 mmol g(-1) L(-1) h(-1) and a quantum yield of 16.1% under visible light (165 W Xe lamp, lambda>420 nm). The results demonstrate that the (CdS)/(ZnS) core/shell nano-particles are a novel photo-catalyst for renewable hydrogen generation from water under visible light. This is attributable to the large band-gap ZnS shell that separates the electron/hole pairs generated by the CdS core and hence reduces their recombinations.

Hydrogen Generation from Al-NiCl2/NaBH4 Mixture Affected by Lanthanum Metal

Directory of Open Access Journals (Sweden)

Wen Qiang Sun

2012-01-01

Full Text Available The effect of La on Al/NaBH4 hydrolysis was elaborated in the present paper. Hydrogen generation amount increases but hydrogen generation rate decreases with La content increasing. There is an optimized composition that Al-15 wt% La-5 wt% NiCl2/NaBH4 mixture (Al-15 wt% La-5 wt% NiCl2/NaBH4 weight ratio, 1 : 3 has 126 mL g−1 min−1 maximum hydrogen generation rate and 1764 mL g−1 hydrogen generation amount within 60 min. The efficiency is 88%. Combined with NiCl2, La has great effect on NaBH4 hydrolysis but has little effect on Al hydrolysis. Increasing La content is helpful to decrease the particle size of Al-La-NiCl2 in the milling process, which induces that the hydrolysis byproduct Ni2B is highly distributed into Al(OH3 and the catalytic reactivity of Ni2B/Al(OH3 is increased therefore. But hydrolysis byproduct La(OH3 deposits on Al surface and leads to some side effect. The Al-La-NiCl2/NaBH4 mixture has good stability in low temperature and its hydrolytic performance can be improved with increasing global temperature. Therefore, the mixture has good safety and can be applied as on board hydrogen generation material.

Hydrogen generation from Al-NiCl2/NaBH4 mixture affected by lanthanum metal.

Science.gov (United States)

Sun, Wen Qiang; Fan, Mei-Qiang; Fei, Yong; Pan, Hua; Wang, Liang Liang; Yao, Jun

2012-01-01

The effect of La on Al/NaBH(4) hydrolysis was elaborated in the present paper. Hydrogen generation amount increases but hydrogen generation rate decreases with La content increasing. There is an optimized composition that Al-15 wt% La-5 wt% NiCl(2)/NaBH(4) mixture (Al-15 wt% La-5 wt% NiCl(2)/NaBH(4) weight ratio, 1 : 3) has 126 mL g(-1 )min(-1) maximum hydrogen generation rate and 1764 mL g(-1) hydrogen generation amount within 60 min. The efficiency is 88%. Combined with NiCl(2), La has great effect on NaBH(4) hydrolysis but has little effect on Al hydrolysis. Increasing La content is helpful to decrease the particle size of Al-La-NiCl(2) in the milling process, which induces that the hydrolysis byproduct Ni(2)B is highly distributed into Al(OH)(3) and the catalytic reactivity of Ni(2)B/Al(OH)(3) is increased therefore. But hydrolysis byproduct La(OH)(3) deposits on Al surface and leads to some side effect. The Al-La-NiCl(2)/NaBH(4) mixture has good stability in low temperature and its hydrolytic performance can be improved with increasing global temperature. Therefore, the mixture has good safety and can be applied as on board hydrogen generation material.

Hydrogen and renewable energy sources integrated system for greenhouse heating

Directory of Open Access Journals (Sweden)

Ileana Blanco

2013-09-01

Full Text Available A research is under development at the Department of Agro- Environmental Sciences of the University of Bari “Aldo Moro” in order to investigate the suitable solutions of a power system based on solar energy (photovoltaic and hydrogen, integrated with a geothermal heat pump for powering a self sustained heated greenhouse. The electrical energy for heat pump operation is provided by a purpose-built array of solar photovoltaic modules, which supplies also a water electrolyser system controlled by embedded pc; the generated dry hydrogen gas is conserved in suitable pressured storage tank. The hydrogen is used to produce electricity in a fuel cell in order to meet the above mentioned heat pump power demand when the photovoltaic system is inactive during winter night-time or the solar radiation level is insufficient to meet the electrical demand. The present work reports some theoretical and observed data about the electrolyzer operation. Indeed the electrolyzer has required particular attention because during the experimental tests it did not show a stable operation and it was registered a performance not properly consistent with the predicted performance by means of the theoretical study.

Cost estimation of hydrogen and DME produced by nuclear heat utilization system. Joint research

International Nuclear Information System (INIS)

Shiina, Yasuaki; Nishihara, Tetsuo

2003-09-01

Research of hydrogen energy has been performed in order to spread use of the hydrogen energy in 2020 or 2030. It will take, however, many years for the hydrogen energy to be used very easily like gasoline, diesel oil and city gas in all of countries. During the periods, low CO 2 release liquid fuels would be used together with hydrogen. Recently, di-methyl-either (DME) has been noticed as one of the substitute liquid fuels of petroleum. Such liquid fuels can be produced from the mixed gas such as hydrogen and carbon oxide which are produced by steam reforming hydrogen generation system by the use of nuclear heat. Therefore, the system would be one of the candidates of future system of nuclear heat utilization. In the present study, we focused on the production of hydrogen and DME. Economic evaluation was estimated for hydrogen and DME production in commercial and nuclear heat utilization plant. At first, heat and mass balance of each process in commercial plant of hydrogen production was estimated and commercial prices of each process were derived. Then, price was estimated when nuclear heat was used instead of required heat of commercial plant. Results showed that the production prices produced by nuclear heat were cheaper by 10% for hydrogen and 3% for DME. With the consideration of reduction effect of CO 2 release, utilization of nuclear heat would be more effective. (author)

Hydrogen generation from hydrolysis of sodium borohydride using Ru(0) nanoclusters as catalyst

International Nuclear Information System (INIS)

Ozkar, S.; Zahmakiran, M.

2005-01-01

Sodium borohydride is stable in aqueous alkaline solution, however, it hydrolyses in water to hydrogen gas in the presence of suitable catalyst. By this way hydrogen can be generated safely for the fuel cells. Generating H 2 catalytically from NaBH 4 solutions has many advantages: NaBH 4 solutions are nonflammable, reaction products are environmentally benign, rate of H 2 generation is easily controlled, the reaction product NaBO 2 can be recycled, H 2 can be generated even at low temperatures. All of the catalysts that has been used in hydrolysis of sodium borohydride are bulk metals and they act as heterogeneous catalysts. The limited surface area of the heterogeneous catalysts causes lower catalytic activity as the activity of catalyst is directly related to its surface area. Thus, the use of metal nanoparticles with large surface area provides potential route to increase the catalytic activity. Here, we report, for the first time, the use of ruthenium(0) nanoclusters as catalyst in the hydrolysis of sodium borohydride liberating hydrogen gas. The ruthenium nanoparticles are generated from the reduction of ruthenium(III) chloride by sodium borohydride in water and stabilized by specific ligand. The ruthenium(0) nanoclusters are found to be highly active catalyst for the hydrolysis of sodium borohydride

Hydrogen generation in SRAT with nitric acid and late washing flowsheets

International Nuclear Information System (INIS)

Hsu, C.W.

1992-01-01

Recently, SRTC recommended two process changes: (1) a final wash of the tetraphenylborate precipitate feed slurry and (2) the use of nitric acid to neutralize the sludge in the SRAT. The first change produced an aqueous hydrolysis product (PHA) with higher formic acid/formate and copper concentration, and reduced the nitrate content in the PHA by an order of magnitude. The second change is to substitute part of formic acid added to the SRAT with nitric acid, and therefore may reduce the hydrogen generated in the SRAT as well as provide nitrate as an oxidant to balance the redox state of the melter feed. The purpose of this report is to determine the pertinent variables that could affect the hydrogen generation rate with these process changes

Development of Al2O3 carrier-Ru composite catalyst for hydrogen generation from alkaline NaBH4 hydrolysis

International Nuclear Information System (INIS)

Huang, Yao-Hui; Su, Chia-Chi; Wang, Shu-Ling; Lu, Ming-Chun

2012-01-01

A recyclable and reusable Ru/Al 2 O 3 catalyst is prepared for hydrogen generation from the hydrolysis process of alkaline sodium borohydride (NaBH 4 ) solution. The hydrogen generation rate by the hydrolysis and methanolysis of alkaline NaBH 4 was explored as a function of NaOH concentration. Meantime, the byproducts derived from the spent alkaline NaBH 4 solution were characterized by X-ray diffraction (XRD), scanning electro microscope/energy dispersive spectrometer (SEM/EDS) and NMR (Nuclear Magnetic Resonance). The effect of NaOH concentration on the hydrogen generation from the hydrolysis of NaBH 4 significantly depends on the type of catalysts. With increasing NaOH concentration, the hydrogen generation rates decrease when using ruthenium (Ru) composite as a catalyst. The hydrogen generation rate of the methanolysis of NaBH 4 is significantly inhibited in the presence of NaOH as compared with the hydrolysis of NaBH 4 . The durability test of the Ru/Al 2 O 3 catalyst shows that the hydrogen generation rate decreases with recycling and reuse. The XRD and NMR analysis results show that the borate hydrate (NaBO 2 H 2 O) was derived from the hydrolysis of 20 wt% and 30 wt% NaBH 4 . -- Highlights: ► A recyclable Ru/Al 2 O 3 catalyst was synthesized for hydrogen generation. ► Ru/Al 2 O 3 significantly promotes the hydrogen generation rate from alkaline NaBH 4 solution. ► The prepared Ru/Al 2 O 3 catalyst can easily collect from the spent alkaline NaBH 4 solution.

Photovoltaic hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Hiser, H.W.; Memory, S.B.; Veziroglu, T.N.; Padin, J. [Univ. of Miami, Coral Gables, FL (United States)

1996-10-01

This is a new project, which started in June 1995, and involves photovoltaic hydrogen production as a fuel production method for the future. In order to increase the hydrogen yield, it was decided to use hybrid solar collectors to generate D.C. electricity, as well as high temperature steam for input to the electrolyzer. In this way, some of the energy needed to dissociate the water is supplied in the form of heat (or low grade energy), to generate steam, which results in a reduction of electrical energy (or high grade energy) needed. As a result, solar to hydrogen conversion efficiency is increased. In the above stated system, the collector location, the collector tracking sub-system (i.e., orientation/rotation), and the steam temperature have been taken as variables. Five locations selected - in order to consider a variety of latitudes, altitudes, cloud coverage and atmospheric conditions - are Atlanta, Denver, Miami, Phoenix and Salt Lake City. Plain PV and hybrid solar collectors for a stationary south facing system and five different collector rotation systems have been analyzed. Steam temperatures have been varied between 200{degrees}C and 1200{degrees}C. During the first year, solar to hydrogen conversion efficiencies have been considered. The results show that higher steam temperatures, 2 dimensional tracking system, higher elevations and dryer climates causes higher conversion efficiencies. Cost effectiveness of the sub-systems and of the overall system will be analyzed during the second year. Also, initial studies will be made of an advanced high efficiency hybrid solar hydrogen production system.

Ultra slow muon generation and thermionic emission of hydrogen isotopes from tungsten surface

International Nuclear Information System (INIS)

Miyake, Yasuhiro

2000-01-01

To generate ultra slow muon, we developed Lyman α light (Lα light) resonance ionization method using 1s-2p-unbound transition. By this method, the desorption process of hydrogen isotope and hydrogen atom generation were studied. In order to generate T atom, the laser resonance ionization of hydrogen nucleus was investigated. When wavelength of VUV light was fixed to 121.52 nm, 1s-2p resonance frequency of T, and VUV light agreed with 355 nm ionization laser in space and time, promising event was observed. The fact showed the resonance ionization method could isolate and detect T atom. By the same method, the experiment of H and D atom were carried out under the condition of the same wavelength of VUV light of 121.57 and 121.53 nm of Lα light, respectively, and the same results were obtained. On the Mu resonance ionization experiment, the light wavelength of VUV was 122.09 nm of Lα of muonium. The results showed the promising event was observed on the expected position of TOF and Mass. The resonance ionization method using Lα light of hydrogen isotope on tungsten film is a very useful method to separate Mu, H, D and T under the same experiment conditions without wavelength of VUV light. (S.Y.)

Hydrogen generation from water using Mg nanopowder produced by arc plasma method

Directory of Open Access Journals (Sweden)

Masahiro Uda, Hideo Okuyama, Tohru S Suzuki and Yoshio Sakka

2012-01-01

Full Text Available We report that hydrogen gas can be easily produced from water at room temperature using a Mg nanopowder (30–1000 nm particles, average diameter 265 nm. The Mg nanopowder was produced by dc arc melting of a Mg ingot in a chamber with mixed-gas atmosphere (20% N2–80% Ar at 0.1 MPa using custom-built nanopowder production equipment. The Mg nanopowder was passivated with a gas mixture of 1% O2 in Ar for 12 h in the final step of the synthesis, after which the nanopowder could be safely handled in ambient air. The nanopowder vigorously reacted with water at room temperature, producing 110 ml of hydrogen gas per 1 g of powder in 600 s. This amount corresponds to 11% of the hydrogen that could be generated by the stoichiometric reaction between Mg and water. Mg(OH2 flakes formed on the surface of the Mg particles as a result of this reaction. They easily peeled off, and the generation of hydrogen continued until all the Mg was consumed.

Techno-economic analysis of an autonomous power system integrating hydrogen technology as energy storage medium

Energy Technology Data Exchange (ETDEWEB)

Tzamalis, G. [Center for Renewable Energy Sources (CRES), RES and Hydrogen Technologies, 19th km Marathon Avenue, GR 19009 Pikermi (Greece); Laboratory of Fuels and Lubricants Technology, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Street, Zografou Campus, 157 80 Athens (Greece); Zoulias, E.I.; Stamatakis, E.; Varkaraki, E. [Center for Renewable Energy Sources (CRES), RES and Hydrogen Technologies, 19th km Marathon Avenue, GR 19009 Pikermi (Greece); Lois, E.; Zannikos, F. [Laboratory of Fuels and Lubricants Technology, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Street, Zografou Campus, 157 80 Athens (Greece)

2011-01-15

Two different options for the autonomous power supply of rural or/and remote buildings are examined in this study. The first one involves a PV - diesel based power system, while the second one integrates RES and hydrogen technologies for the development of a self - sustained power system. The main objective is the replacement of the diesel generator and a comparison between these two options for autonomous power supply. Model simulations of the two power systems before and after the replacement, an optimization of the component sizes and a techno - economic analysis have been performed for the purpose of this study. A sensitivity analysis taking into account future cost scenarios for hydrogen technologies is also presented. The results clearly show that the Cost of Energy Produced (COE) from the PV - hydrogen technologies power system is extremely higher than the PV - diesel power system. However, the adopted PV - hydrogen technologies power system reduces to zero the Green - House Gas (GHG) emissions. Moreover, the sensitivity analysis indicates that COE for the latter system can be further reduced by approximately 50% compared to its initial value. This could be achieved by reducing critical COE's parameters, such as PEM electrolyser and fuel cell capital costs. Hence, a possible reduction on the capital costs of hydrogen energy equipment in combination with emissions reduction mentioned above could make hydrogen - based power systems more competitive. (author)

Sunlight to hydrogen conversion: Design optimization and energy management of concentrated photovoltaic (CPV-Hydrogen) system using micro genetic algorithm

KAUST Repository

Burhan, Muhammad

2016-02-14

Owing to the intermittent solar irradiance from cloud cover in the diurnal period and unavailability at night time, the practical design of a solar system requires energy backup storage for an uninterrupted supply or for off-grid operation. However, for highly efficient CPV (concentrated photovoltaic) system, the literature is lacking for energy management and optimization algorithm and tool for standalone operation. In this paper, a system with CPV and electrolyser is presented where beam irradiance of sunlight is harnessed to convert the instantaneously generated electricity into useful Hydrogen/Oxygen gas, where they can be stored and re-used for downstream applications such as the fuel cells, etc. The multi-variable design and multi-objective optimization strategies are proposed and presented for a standalone operation of the CPV-Hydrogen system as well as their system performances, particularly electrical rating of CPV based upon the real weather data of Singapore. © 2016 Elsevier Ltd.

Optimization of the photovoltaic-hydrogen supply system of a stand-alone remote-telecom application

Energy Technology Data Exchange (ETDEWEB)

Gomez, Guillermo; Martinez, Graciano; Galvez, Jose L.; Cuevas, Raquel; Maellas, Jesus [National Institute for Aerospace Technology (INTA), Renewable Energy Department, Ctra. Ajalvir km 4, E-28850 Torrejon de Ardoz, Madrid (Spain); Gila, Raul; Bueno, Emilio [Polytechnical School - Alcala de Henares University, Electronics Department, Campus Universitario, Ctra. De Madrid-Barcelona Km 33.600, Alcala de Henares, Madrid (Spain)

2009-07-15

Hydrogen is considered as the optimal carrier for the surplus energy storage from renewable resources. Although hydrogen and its application in fuel cell is considered as a high-cost energy system, some cost-efficient solutions have been found for their use in stand-alone applications, which usually depend on the variability of renewable sources that have to be oversized in order to reduce their dependence on external energy sources. This paper shows the results from the simulation of several alternatives of introducing hydrogen technologies to increase the independence of a remote-telecom application fed by photovoltaic panels. Hydrogen is obtained by electrolysis and it is used in a fuel cell when the renewable energy source is not enough to maintain the stand-alone application. TRNSYS simulation environment has been used for evaluating the proposed alternatives. The results show that the best configuration option is that considering the use of hydrogen as a way to storage the surplus of radiation and the management system can vary the number of photovoltaic panels assigned to feed the hydrogen generation, the batteries or the telecom application. (author)

Artificial neural networks and neuro-fuzzy inference systems as virtual sensors for hydrogen safety prediction

Energy Technology Data Exchange (ETDEWEB)

Karri, Vishy; Ho, Tien [School of Engineering, University of Tasmania, GPO Box 252-65, Hobart, Tasmania 7001 (Australia); Madsen, Ole [Department of Production, Aalborg University, Fibigerstraede 16, DK-9220 Aalborg (Denmark)

2008-06-15

Hydrogen is increasingly investigated as an alternative fuel to petroleum products in running internal combustion engines and as powering remote area power systems using generators. The safety issues related to hydrogen gas are further exasperated by expensive instrumentation required to measure the percentage of explosive limits, flow rates and production pressure. This paper investigates the use of model based virtual sensors (rather than expensive physical sensors) in connection with hydrogen production with a Hogen 20 electrolyzer system. The virtual sensors are used to predict relevant hydrogen safety parameters, such as the percentage of lower explosive limit, hydrogen pressure and hydrogen flow rate as a function of different input conditions of power supplied (voltage and current), the feed of de-ionized water and Hogen 20 electrolyzer system parameters. The virtual sensors are developed by means of the application of various Artificial Intelligent techniques. To train and appraise the neural network models as virtual sensors, the Hogen 20 electrolyzer is instrumented with necessary sensors to gather experimental data which together with MATLAB neural networks toolbox and tailor made adaptive neuro-fuzzy inference systems (ANFIS) were used as predictive tools to estimate hydrogen safety parameters. It was shown that using the neural networks hydrogen safety parameters were predicted to less than 3% of percentage average root mean square error. The most accurate prediction was achieved by using ANFIS. (author)

Design of the steam generator in an energy conversion system based on the aluminum combustion with water

International Nuclear Information System (INIS)

Mercati, Stefano; Milani, Massimo; Montorsi, Luca; Paltrinieri, Fabrizio

2012-01-01

Highlights: ► Development of a numerical approach for the analysis of a co-generation system based on the aluminum water reaction. ► Construction of system operating maps for estimating the system behavior. ► Comparison of two different designs of the steam generator for the system. ► Definition of the operating range where each configuration provides the best performance. -- Abstract: The paper shows the preliminary design of the superheated steam generator to be used in a novel hydrogen production and energy conversion system based on the combustion of aluminum particles with water. The system is aimed at producing hydrogen and pressurized superheated steam, using the heat released by the Al–H 2 O reaction. The interest on this type of technology arises because of the possibility of obtaining hydrogen with very low pollutant and greenhouse gas emissions, compared to the traditional hydrogen production systems, such as the steam reforming from methane. The analysis of the combustion chamber and the heat recovery system is carried out by means of a lumped and distributed parameter numerical approach. The multi phase and gas mixture theoretical principles are used both to characterize the mass flow rate and the heat release in the combustion chamber and within the heat exchangers in order to relate the steam generator performance to the system operating parameters. Finally, the influence of the steam generator performance on the whole energy conversion system behavior is addressed, with particular care to the evaluation of the total power and efficiency variation with the combustion parameters.

Economic Dispatch of Hydrogen Systems in Energy Spot Markets

DEFF Research Database (Denmark)

You, Shi; Nørgård, Per Bromand

2015-01-01

of energy spot markets. The generic hydrogen system is comprised of an electrolysis for hydrogen production, a hydrogen storage tank and a fuel cell system for cogeneration of electricity and heat. A case study is presented with information from practical hydrogen systems and the Nordic energy markets...

Photocatalytic hydrogen generation over Eosin Y-Sensitized TS-1 zeolite

International Nuclear Information System (INIS)

Zhang Xiaojie; Jin Zhiliang; Li Yuexiang; Li Shuben; Lu Gongxuan

2008-01-01

Eosin Y-sensitized TS-1 zeolite was studied for the photo-reduction of water into hydrogen driven by visible light (λ ≥ 420 nm). The optimal pH and weight ratio between Eosin Y and TS-1 zeolite is 7 and 1/8, respectively. In the presence of triethanolamine (TEA) as an electron donor, the highest rate of hydrogen generation and apparent quantum efficiency are 34 μmol h -1 and 9.4%, respectively, under visible light irradiation (λ ≥ 420 nm). Short-term stability test indicates that the catalyst is rather stable during 50 h photoreaction

Photocatalytic hydrogen generation over Eosin Y-Sensitized TS-1 zeolite

Energy Technology Data Exchange (ETDEWEB)

Zhang Xiaojie [State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Tianshui Zhong Road 18, Lanzhou 730000 (China); Graduate University of the Chinese Academy of Sciences, Beijing 100101 (China); Jin Zhiliang [State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Tianshui Zhong Road 18, Lanzhou 730000 (China); Li Yuexiang [Department of Chemistry, Nanchang University, Nanjing Road 245, Nanchang 330047 (China); Li Shuben [State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Tianshui Zhong Road 18, Lanzhou 730000 (China); Lu Gongxuan [State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Tianshui Zhong Road 18, Lanzhou 730000 (China)], E-mail: gxlu@lzb.ac.cn

2008-05-30

Eosin Y-sensitized TS-1 zeolite was studied for the photo-reduction of water into hydrogen driven by visible light ({lambda} {>=} 420 nm). The optimal pH and weight ratio between Eosin Y and TS-1 zeolite is 7 and 1/8, respectively. In the presence of triethanolamine (TEA) as an electron donor, the highest rate of hydrogen generation and apparent quantum efficiency are 34 {mu}mol h{sup -1} and 9.4%, respectively, under visible light irradiation ({lambda} {>=} 420 nm). Short-term stability test indicates that the catalyst is rather stable during 50 h photoreaction.

Hydrogen generation utilizing integrated CO2 removal with steam reforming

Science.gov (United States)

Duraiswamy, Kandaswamy; Chellappa, Anand S

2013-07-23

A steam reformer may comprise fluid inlet and outlet connections and have a substantially cylindrical geometry divided into reforming segments and reforming compartments extending longitudinally within the reformer, each being in fluid communication. With the fluid inlets and outlets. Further, methods for generating hydrogen may comprise steam reformation and material adsorption in one operation followed by regeneration of adsorbers in another operation. Cathode off-gas from a fuel cell may be used to regenerate and sweep the adsorbers, and the operations may cycle among a plurality of adsorption enhanced reformers to provide a continuous flow of hydrogen.

Cryogenic system for liquid hydrogen polarimeter

International Nuclear Information System (INIS)

Kitami, T.; Chiba, M.; Hirabayashi, H.; Ishii, T.; Kato, S.

1979-01-01

A cryogenic system has been constructed for a liquid hydrogen polarimeter in order to measure polarization of high energy proton at the 1.3 GeV electron synchrotron of Institute for Nuclear Study, University of Tokyo. The system principally consists of a cryogenerator with a cryogenic transfer line, a liquid hydrogen cryostat, and a 14.5 l target container of thin aluminum alloy where liquid hydrogen is served for the experiment. The refrigeration capacity is about 54 W at 20.4 K without a target container. (author)

Generation of core–shell nanoparticles Al@Ti by laser ablation in liquid for hydrogen storage

Energy Technology Data Exchange (ETDEWEB)

Serkov, A.A. [Wave Research Center of A.M. Prokhorov General Physics Institute of the Russian Academy of Sciences, 38, Vavilov street, 119991 Moscow (Russian Federation); The Federal State Educational Institution of Higher Professional Education, “Moscow Institute of Physics and Technology (State University)”, 9, Institutsky lane, 141700, Dolgoprudny, Moscow (Russian Federation); Barmina, E.V.; Simakin, A.V. [Wave Research Center of A.M. Prokhorov General Physics Institute of the Russian Academy of Sciences, 38, Vavilov street, 119991 Moscow (Russian Federation); Kuzmin, P.G., E-mail: qzzzma@gmail.com [Wave Research Center of A.M. Prokhorov General Physics Institute of the Russian Academy of Sciences, 38, Vavilov street, 119991 Moscow (Russian Federation); Voronov, V.V. [A.M. Prokhorov General Physics Institute of the Russian Academy of Sciences, 38, Vavilov street, 119991 Moscow (Russian Federation); Shafeev, G.A. [Wave Research Center of A.M. Prokhorov General Physics Institute of the Russian Academy of Sciences, 38, Vavilov street, 119991 Moscow (Russian Federation); National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), 31, Kashirskoye highway, 115409 Moscow (Russian Federation)

2015-09-01

Highlights: • Core–shell Al@Ti NPs are generated by laser ablation in isopropanol. • Isopropanol was saturated with molecular hydrogen. • The composite metallic Al-Ti target was used. • HR TEM characterization shows that Ti core is covered by epitaxial Al shell. • Al@Ti NPs are promising for hydrogen storage. - Abstract: Core–shell Al@Ti nanoparticles are generated by ablation of a composite Ti–Al target in liquid isopropanol saturated with molecular hydrogen using a Nd:YAG laser with pulse duration of 10 ps and repetition rate of 200 kHz. The target is made of two plates of corresponding metals stacked together and placed into a flowing cell reactor. Transmission Electron Microscopy analysis of generated NPs reveals their core–shell structure with Ti core and Al shell. Average size of NPs determined by means of measuring disk centrifuge is around 40 nm. Saturation of NPs by hydrogen is due to sharp dependence of its solubility in these metals on temperature. XRD studies of generated NPs show the peaks of both metallic Ti and Al with some amount of TiO{sub 2}. No peaks of Ti–Al alloys are observed.

Generation of oxy-hydrogen gas and its effect on performance of spark ignition engine

Science.gov (United States)

Patil, N. N.; Chavan, C. B.; More, A. S.; Baskar, P.

2017-11-01

Considering the current scenario of petroleum fuels, it has been observed that, they will last for few years from now. On the other hand, the ever increasing cost of a gasoline fuels and their related adverse effects on environment caught the attention of researchers to find a supplementary source. For commercial fuels, supplementary source is not about replacing the entire fuel, instead enhancing efficiency by simply making use of it in lesser amount. From the recent research that has been carried out, focus on the use of Hydrogen rich gas as a supplementary source of fuel has increased. But the problem related to the storage of hydrogen gas confines the application of pure hydrogen in petrol engine. Using oxy-hydrogen gas (HHO) generator the difficulties of storing the hydrogen have overcome up to a certain limit. The present study highlights on performance evaluation of conventional petrol engine by using HHO gas as a supplementary fuel. HHO gas was generated from the electrolysis of water. KOH solution of 3 Molar concentration was used which act as a catalyst and accelerates the rate of generation of HHO gas. Quantity of gas to be supplied to the engine was controlled by varying amount of current. It was observed that, engine performance was improved on the introduction of HHO gas.

Conceptual study on HTGR-IS hydrogen supply system using organic hydrides

International Nuclear Information System (INIS)

Terada, Atsuhiko; Noguchi, Hiroki; Takegami, Hiroaki; Kamiji, Yu; Inagaki, Yoshiyuki

2012-02-01

We have proposed a hydrogen supply-chain system, which is a storage/supply system of large amount of hydrogen produced by HTGR-IS hydrogen production system. The organic chemical hydride method is one of the candidate techniques in the system for hydrogen storage and transportation. In this study, properties of organic hydrides and conventional hydrogen storage/supply system were surveyed to make use of the conceptual design of the hydrogen supply system using an organic hydrides method with VHTR-IS hydrogen production process (hydrogen production: 85,400 Nm 3 /h). Conceptual specifications of the main equipments were designed for the hydrogen supply system consisting of hydrogenation and dehydrogenation process. It was also clarified the problems of hydrogen supply system, such as energy efficiency and system optimization. (author)

Two step novel hydrogen system using additives to enhance hydrogen release from the hydrolysis of alane and activated aluminum

Science.gov (United States)

Zidan, Ragaiy; Teprovich, Joseph A.; Motyka, Theodore

2015-12-01

A system for the generation of hydrogen for use in portable power systems is set forth utilizing a two-step process that involves the thermal decomposition of AlH.sub.3 (10 wt % H.sub.2) followed by the hydrolysis of the activated aluminum (Al*) byproduct to release additional H.sub.2. Additionally, a process in which water is added directly without prior history to the AlH.sub.3:PA composite is also disclosed.

Hydrogen generation from deliquescence of ammonia borane using Ni-Co/r-GO catalyst

Science.gov (United States)

Chou, Chang-Chen; Chen, Bing-Hung

2015-10-01

Hydrogen generation from the catalyzed deliquescence/hydrolysis of ammonia borane (AB) using the Ni-Co catalyst supported on the graphene oxide (Ni-Co/r-GO catalyst) under the conditions of limited water supply was studied with the molar feed ratio of water to ammonia borane (denoted as H2O/AB) at 2.02, 3.97 and 5.93, respectively. The conversion efficiency of ammonia borane to hydrogen was estimated both from the cumulative volume of the hydrogen gas generated and the conversion of boron chemistry in the hydrolysates analyzed by the solid-state 11B NMR. The conversion efficiency of ammonia borane could reach nearly 100% under excess water dosage, that is, H2O/AB = 3.97 and 5.93. Notably, the hydrogen storage capacity could reach as high as 6.5 wt.% in the case with H2O/AB = 2.02. The hydrolysates of ammonia borane in the presence of Ni-Co/r-GO catalyst were mainly the mixture of boric acid and metaborate according to XRD, FT-IR and solid-state 11B NMR analyses.

Techno-economical Analysis of Hybrid PV-WT-Hydrogen FC System for a Residential Building with Low Power Consumption

Directory of Open Access Journals (Sweden)

Badea G.

2016-12-01

Full Text Available This paper shows a techno-economical analysis on performance indicators of hybrid solar-wind-hydrogen power generation system which supply with electricity a low - energy building, located in Cluj-Napoca. The case study had the main objectives, as follows: cost estimation, evaluation of energy and environmental performance for a fuel cell integrated into a small-scale hybrid system power generation and estimation of electrolytic hydrogen production based on renewable energy resources available on the proposed site. The results presented in this paper illustrate a case study for location Cluj-Napoca. The wind and solar resource can play an important role in energy needs for periods with "peak load" or intermittent energy supply. However, hydrogen production is dependent directly proportional to the availability of renewable energy resources, but the hydrogen can be considered as a storage medium for these renewable resources. It can be said that this study is a small-scale model analysis, a starting point for a detailed analysis of Romania's potential electrolytic production of hydrogen from renewable resources and supply electricity using fuel cells integrated into hybrid energy systems.

Sunlight to hydrogen conversion: Design optimization and energy management of concentrated photovoltaic (CPV-Hydrogen) system using micro genetic algorithm

International Nuclear Information System (INIS)

Burhan, Muhammad; Chua, Kian Jon Ernest; Ng, Kim Choon

2016-01-01

Owing to the intermittent solar irradiance from cloud cover in the diurnal period and unavailability at night time, the practical design of a solar system requires energy backup storage for an uninterrupted supply or for off-grid operation. However, for highly efficient CPV (concentrated photovoltaic) system, the literature is lacking for energy management and optimization algorithm and tool for standalone operation. In this paper, a system with CPV and electrolyser is presented where beam irradiance of sunlight is harnessed to convert the instantaneously generated electricity into useful Hydrogen/Oxygen gas, where they can be stored and re-used for downstream applications such as the fuel cells, etc. The multi-variable design and multi-objective optimization strategies are proposed and presented for a standalone operation of the CPV-Hydrogen system as well as their system performances, particularly electrical rating of CPV based upon the real weather data of Singapore. - Highlights: • Design modelling and energy management strategy is proposed for CPV-Hydrogen system. • Micro GA does multi-variable and multi-objective optimization for standalone operation. • Design is verified and analysed for minimum cost, zero PSFT and optimal storage. • Performance of each component is presented for different real weather data conditions. • Proposed design approach is applicable in all regions with low and high DNI.

Graphene sheets/cobalt nanocomposites as low-cost/high-performance catalysts for hydrogen generation

International Nuclear Information System (INIS)

Zhang, Fei; Hou, Chengyi; Zhang, Qinghong; Wang, Hongzhi; Li, Yaogang

2012-01-01

The production of clean and renewable hydrogen through the hydrolysis of sodium borohydride has received much attention owing to increasing global energy demands. Graphene sheets/cobalt (GRs/Co) nanocomposites, which are highly efficient catalysts, have been prepared using a one-step solvothermal method in ethylene glycol. Co 2+ salts were converted to Co nanoparticles, which were simultaneously inserted into the graphene layers with the reduction of graphite oxide sheets to GRs. The as-synthesized samples were characterized by X-ray diffraction, Fourier transform infrared spectra, Raman spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy and vibrating sample magnetometer. The maximum saturation magnetization value reached 80.8 emu g −1 , meaning they are more suitable for magnet-controlled generation of H 2 than noble metal catalysts. The catalytic activity of the composite was investigated by the hydrolysis of sodium borohydride in aqueous solution both with and without a GRs support. It was found that the high electronic conductive GRs support increased the hydrogen generation rate (about two times) compared with pure cobalt. The improved hydrogen generation rate, low cost and uncomplicated recycling makes the GRs/Co nanocomposites promising candidates as catalysts for hydrogen generation. Highlights: ► Graphene sheets/cobalt nanocomposites were prepared by a one-step solvothermal method. ► The maximum saturation magnetization value of the composites reached 80.8 emu g −1 . ► The graphene support greatly increased the catalytic activity of cobalt. ► An easily removed, recycled and controlled functional filter was obtained.

Reforming of natural gas—hydrogen generation for small scale stationary fuel cell systems

Science.gov (United States)

Heinzel, A.; Vogel, B.; Hübner, P.

The reforming of natural gas to produce hydrogen for fuel cells is described, including the basic concepts (steam reforming or autothermal reforming) and the mechanisms of the chemical reactions. Experimental work has been done with a compact steam reformer, and a prototype of an experimental reactor for autothermal reforming was tested, both containing a Pt-catalyst on metallic substrate. Experimental results on the steam reforming system and a comparison of the steam reforming process with the autothermal process are given.

Advanced compressed hydrogen fuel storage systems

International Nuclear Information System (INIS)

Jeary, B.

2000-01-01

Dynetek was established in 1991 by a group of private investors, and since that time efforts have been focused on designing, improving, manufacturing and marketing advanced compressed fuel storage systems. The primary market for Dynetek fuel systems has been Natural Gas, however as the automotive industry investigates the possibility of using hydrogen as the fuel source solution in Alternative Energy Vehicles, there is a growing demand for hydrogen storage on -board. Dynetek is striving to meet the needs of the industry, by working towards developing a fuel storage system that will be efficient, economical, lightweight and eventually capable of storing enough hydrogen to match the driving range of the current gasoline fueled vehicles

Operation of the cryotron relaxation generator in solid argon and hydrogen

International Nuclear Information System (INIS)

Rakhubvsky, V.A.

2008-01-01

The research results of the cryotron relaxation generator (CRG) operation in solid argon, normal hydrogen and parahydrogen have been given. The frequency transition times for CRG at different values of cooling the solid gas have been measured

Large area imaging of hydrogenous materials using fast neutrons from a DD fusion generator

Energy Technology Data Exchange (ETDEWEB)

Cremer, J.T., E-mail: ted@adelphitech.com [Adelphi Technology Inc., 2003 East Bayshore Road, Redwood City, California 94063 (United States); Williams, D.L.; Gary, C.K.; Piestrup, M.A.; Faber, D.R.; Fuller, M.J.; Vainionpaa, J.H.; Apodaca, M. [Adelphi Technology Inc., 2003 East Bayshore Road, Redwood City, California 94063 (United States); Pantell, R.H.; Feinstein, J. [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States)

2012-05-21

A small-laboratory fast-neutron generator and a large area detector were used to image hydrogen-bearing materials. The overall image resolution of 2.5 mm was determined by a knife-edge measurement. Contact images of objects were obtained in 5-50 min exposures by placing them close to a plastic scintillator at distances of 1.5 to 3.2 m from the neutron source. The generator produces 10{sup 9} n/s from the DD fusion reaction at a small target. The combination of the DD-fusion generator and electronic camera permits both small laboratory and field-portable imaging of hydrogen-rich materials embedded in high density materials.

Hydrogen generation, distribution and combustion under severe LWR accident conditions: a state-of-technology report

International Nuclear Information System (INIS)

Postma, A.K.; Hilliard, R.K.

1983-03-01

This report reviews the current state of technology regarding hydrogen safety issues in light water reactor plants. Topics considered in this report include hydrogen generation, distribution in containment, and combustion characteristics. A companion report addresses hydrogen control. The objectives of the study were to identify the key safety issues related to hydrogen produced under severe accident conditions, to describe the state of technology for each issue, and to point out ongoing programs aimed at resolving the open issues

Hydrogen production in a PWR during LOCA

International Nuclear Information System (INIS)

Cassette, P.

1984-01-01

Hydrogen generation during a PWR LOCA has been estimated for design basis accident and for two more severe hypothetical accidents. Hydrogen production during design basis accident is a rather slow mechanism, allowing in the worst case, 15 days to connect a hydrogen recombining unit to the containment atmosphere monitoring system. Hydrogen generated by steam oxidation during more severe hypothetical accidents was found limited by steam availability and fuel melting phenomena. Uncertainty is, however, still remaining on corium-zirconium-steam interaction. In the worst case, calculations lead to the production of 500 kg of hydrogen, thus leading to a volume concentration of 15% in containment atmosphere, assuming homogeneous hydrogen distribution within the reactor building. This concentration is within flammability limits but not within detonation limits. However, hydrogen detonation due to local hydrogen accumulation cannot be discarded. A major uncertainty subsisting on hydrogen hazard is hydrogen distribution during the first hours of the accident. This point determines the effects and consequences of local detonation or deflagration which could possibly be harmful to safeguard systems, or induce missile generation in the reactor building. As electrical supply failures are identified as an important contributor to severe accident risk, corrective actions have been taken in France to improve their reliability, including the installation of a gas turbine on each site to supplement the existing sources. These actions are thus contributing to hydrogen hazard reduction

Computer systems and software description for Standard-E+ Hydrogen Monitoring System (SHMS-E+)

International Nuclear Information System (INIS)

Tate, D.D.

1997-01-01

The primary function of the Standard-E+ Hydrogen Monitoring System (SHMS-E+) is to determine tank vapor space gas composition and gas release rate, and to detect gas release events. Characterization of the gas composition is needed for safety analyses. The lower flammability limit, as well as the peak burn temperature and pressure, are dependent upon the gas composition. If there is little or no knowledge about the gas composition, safety analyses utilize compositions that yield the worst case in a deflagration or detonation. Knowledge of the true composition could lead to reductions in the assumptions and therefore there may be a potential for a reduction in controls and work restrictions. Also, knowledge of the actual composition will be required information for the analysis that is needed to remove tanks from the Watch List. Similarly, the rate of generation and release of gases is required information for performing safety analyses, developing controls, designing equipment, and closing safety issues. This report outlines the computer system design layout description for the Standard-E+ Hydrogen Monitoring System

Economic Assessment of Hydrogen Technologies Participating in California Electricity Markets

Energy Technology Data Exchange (ETDEWEB)

Eichman, Joshua [National Renewable Energy Lab. (NREL), Golden, CO (United States); Townsend, Aaron [National Renewable Energy Lab. (NREL), Golden, CO (United States); Melaina, Marc [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-02-19

As the electric sector evolves and increasing amounts of variable renewable generation are installed on the system, there are greater needs for system flexibility and sufficient capacity, and greater concern for overgeneration from renewable sources not well matched in time with electric loads. Hydrogen systems have the potential to support the grid in each of these areas. However, limited information is available about the economic competitiveness of hydrogen system configurations. This paper quantifies the value for hydrogen energy storage and demand response systems to participate in select California wholesale electricity markets using 2012 data. For hydrogen systems and conventional storage systems (e.g., pumped hydro, batteries), the yearly revenues from energy, ancillary service, and capacity markets are compared to the yearly cost to establish economic competitiveness. Hydrogen systems can present a positive value proposition for current markets. Three main findings include: (1) For hydrogen systems participating in California electricity markets, producing and selling hydrogen was found to be much more valuable than producing and storing hydrogen to later produce electricity; therefore systems should focus on producing and selling hydrogen and opportunistically providing ancillary services and arbitrage. (2) Tighter integration with electricity markets generates greater revenues (i.e., systems that participate in multiple markets receive the highest revenue). (3) More storage capacity, in excess of what is required to provide diurnal shifting, does not increase competitiveness in current California wholesale energy markets. As more variable renewable generation is installed, the importance of long duration storage may become apparent in the energy price or through additional markets, but currently, there is not a sufficiently large price differential between days to generate enough revenue to offset the cost of additional storage. Future work will involve

Hydrogen generation through static-feed water electrolysis

Science.gov (United States)

Jensen, F. C.; Schubert, F. H.

1975-01-01

A static-feed water electrolysis system (SFWES), developed under NASA sponsorship, is presented for potential applicability to terrestrial hydrogen production. The SFWES concept uses (1) an alkaline electrolyte to minimize power requirements and materials-compatibility problems, (2) a method where the electrolyte is retained in a thin porous matrix eliminating bulk electrolyte, and (3) a static water-feed mechanism to prevent electrode and electrolyte contamination and to promote system simplicity.

Co-generation of hydrogen from nuclear and wind: the effect on costs of realistic variations in wind generation. Paper no. IGEC-1-094

International Nuclear Information System (INIS)

Miller, A.I.; Duffey, R.B.

2005-01-01

Can electricity from high-capacity nuclear reactors be blended with the variable output of wind turbines to produce electrolytic hydrogen competitively? To be competitive with alternative sources, hydrogen produced by conventional electrolysis requires low-cost electricity (likely <2.5 cents US/kW.h). One approach is to operate interruptibly, allowing an installation to sell electricity when the grid price is high and to make hydrogen when it is low. Our previous studies show that this could be cost-competitive using nuclear power generator producing electricity around 3 cents US/kW.h. Although similar unit costs are projected for wind-generated electricity, idleness of the electrolysis facility due to the variability of wind-generated electricity imposes a significant cost penalty. This paper reports on ongoing work on the economics of blending electricity from nuclear and wind sources by using wind-generated power, when available, to augment the current through electrolysis equipment that is primarily nuclear-powered - a concept we call NuWind. A voltage penalty accompanies the higher current. A 10% increase in capital cost for electrolysis equipment to enable it to accommodate the higher rate of hydrogen generation is still substantially cheaper than the capital cost of wind-dedicated electrolysis. Real-time data for electricity costs have been combined with real-time wind variability. The variability in wind fields between sites was accommodated by assigning average wind speeds that produced an average electricity generation from wind of between 32 and 42% of peak capacity, which is typical of the expectations for superior wind-generation sites. (author)

Hydrogen storage and delivery system development: Analysis

Energy Technology Data Exchange (ETDEWEB)

Handrock, J.L. [Sandia National Labs., Livermore, CA (United States)

1996-10-01

Hydrogen storage and delivery is an important element in effective hydrogen utilization for energy applications and is an important part of the FY1994-1998 Hydrogen Program Implementation Plan. This project is part of the Field Work Proposal entitled Hydrogen Utilization in Internal Combustion Engines (ICE). The goal of the Hydrogen Storage and Delivery System Development Project is to expand the state-of-the-art of hydrogen storage and delivery system design and development. At the foundation of this activity is the development of both analytical and experimental evaluation platforms. These tools provide the basis for an integrated approach for coupling hydrogen storage and delivery technology to the operating characteristics of potential hydrogen energy use applications. Results of the analytical model development portion of this project will be discussed. Analytical models have been developed for internal combustion engine (ICE) hybrid and fuel cell driven vehicles. The dependence of hydride storage system weight and energy use efficiency on engine brake efficiency and exhaust temperature for ICE hybrid vehicle applications is examined. Results show that while storage system weight decreases with increasing engine brake efficiency energy use efficiency remains relatively unchanged. The development, capability, and use of a recently developed fuel cell vehicle storage system model will also be discussed. As an example of model use, power distribution and control for a simulated driving cycle is presented. Model calibration results of fuel cell fluid inlet and exit temperatures at various fuel cell idle speeds, assumed fuel cell heat capacities, and ambient temperatures are presented. The model predicts general increases in temperature with fuel cell power and differences between inlet and exit temperatures, but under predicts absolute temperature values, especially at higher power levels.

计算机控制太阳能光伏水制氢及储能发电系统的研究%Study on the Solar Photovoltaic Water Hydrogen Production and Energy Storage&Power Generation System Based on the Computer Control

Institute of Scientific and Technical Information of China (English)

秦天像; 任小勇; 杨天虎

2015-01-01

虽然太阳能、氢能利用技术有很多优势,但太阳能资源间歇性不稳定所带来的可靠性低的缺陷却影响着负载的连续使用. 太阳能光伏水制氢及储能发电系统能通过计算机控制提供稳定可靠的电能,具有很高的推广应用价值. 从太阳能光伏水制氢发电系统、计算机控制电解水制氢系统、储氢技术、氢能利用技术等方面,详细介绍了计算机控制太阳能光伏水制氢及储能发电系统的功能.%Although the solar energy and hydrogen energy utilization technologies have many advantages, the defect of low reliability caused by the intermittent instability of solar energy resources affects the continuous use of the load . The solar photovoltaic water hydrogen production and energy storage&power generation system, which can provide stable and reliable electricity through the computer control, has very high value of application. This paper introduces in detail the functions of the solar photovoltaic water hydrogen production and energy storage&power generation system from aspects of the solar photovoltaic water hydrogen power generation system, computer-based water electrolysis hydrogen production system, hydrogen storage technology, and hydrogen power utilization technology, etc.

Enhanced hydrogen generation by hydrolysis of Mg doped with flower-like MoS2 for fuel cell applications

Science.gov (United States)

Huang, Minghong; Ouyang, Liuzhang; Liu, Jiangwen; Wang, Hui; Shao, Huaiyu; Zhu, Min

2017-10-01

In this work, flower-like MoS2 spheres are synthesized via a hydrothermal method and the catalytic activity of the as-prepared and bulk MoS2 on hydrolysis of Mg is systematically investigated for the first time. The Mg-MoS2 composites are prepared by ball milling and the hydrogen generation performances of the composites are investigated in 3.5% NaCl solution. The experimental results suggest that the as-prepared MoS2 exhibits better catalytic effect on hydrolysis of Mg compared to bulk MoS2. In particular, Mg-10 wt% MoS2 (as-prepared) composite milled for 1 h shows the best hydrogen generation properties and releases 90.4% of theoretical hydrogen generation capacity within 1 min at room temperature. The excellent catalytic effect of as-prepared MoS2 may be attributed to the following aspects: three-dimensional flower-like MoS2 architectures improve its dispersibility on Mg particles; make the composite more reactive; hamper the generated Mg(OH)2 from adhering to the surface of Mg; and increase the galvanic corrosion of Mg. In addition, a hydrogen generator based on the hydrolysis reaction of Mg-0.2 wt% MoS2 composite is manufactured and it can supply a maximum hydrogen flow rate of 2.5 L/min. The findings here demonstrate the as-prepared flower-like MoS2 can be a promising catalyst for hydrogen generation from Mg.

Single-crystal neutron diffraction studies of hydrogen-bonded systems: Two recent examples from IPNS

Energy Technology Data Exchange (ETDEWEB)

Koetzle, Thomas F. [IPNS Division, Argonne National Laboratory, Argonne, IL 60439 (United States)], E-mail: tkoetzle@anl.gov; Piccoli, Paula M.B.; Schultz, Arthur J. [IPNS Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

2009-02-21

Beginning with work in the 1950s at the first generation of research reactors, studies of hydrogen-bonded systems have been a prime application for single-crystal neutron diffraction. The range of systems studied was extended in the 1960s and 1970s, with the advent of high flux reactor sources, and beginning around 1980 studies at pulsed neutron sources have made increasingly important contributions. Recently at the Argonne Intense Pulsed Neutron Source (IPNS), working with collaborators, we completed two studies of hydrogen-bonded systems that will serve to illustrate topics of current interest. In the first study, on andrographolide, an active diterpenoid natural product, our neutron diffraction results definitively characterize the hydrogen-bonding interactions. The second IPNS study is on tetraacetylethane (TAE), a {beta}-diketone enol system with a very short, strong intramolecular O-H...O hydrogen bond. At IPNS, we have determined the neutron crystal structure of TAE at five temperatures between 20 and 298 K to investigate changes in the structure with temperature and to probe for disorder. Despite the successes illustrated by the two examples presented here and by many other studies, at present applications of single-crystal neutron diffraction continue to be extremely flux limited and constrained by the requirement for mm-size crystals for many problems. These limitations are being addressed through the realization of powerful instruments at a new generation of pulsed neutron sources, including in the USA the TOPAZ and MaNDi single-crystal diffractometers that are under development at the Spallation Neutron Source (SNS)

Single-crystal neutron diffraction studies of hydrogen-bonded systems: Two recent examples from IPNS

Science.gov (United States)

Koetzle, Thomas F.; Piccoli, Paula M. B.; Schultz, Arthur J.

2009-02-01

Beginning with work in the 1950s at the first generation of research reactors, studies of hydrogen-bonded systems have been a prime application for single-crystal neutron diffraction. The range of systems studied was extended in the 1960s and 1970s, with the advent of high flux reactor sources, and beginning around 1980 studies at pulsed neutron sources have made increasingly important contributions. Recently at the Argonne Intense Pulsed Neutron Source (IPNS), working with collaborators, we completed two studies of hydrogen-bonded systems that will serve to illustrate topics of current interest. In the first study, on andrographolide, an active diterpenoid natural product, our neutron diffraction results definitively characterize the hydrogen-bonding interactions. The second IPNS study is on tetraacetylethane (TAE), a β-diketone enol system with a very short, strong intramolecular O-H⋯O hydrogen bond. At IPNS, we have determined the neutron crystal structure of TAE at five temperatures between 20 and 298 K to investigate changes in the structure with temperature and to probe for disorder. Despite the successes illustrated by the two examples presented here and by many other studies, at present applications of single-crystal neutron diffraction continue to be extremely flux limited and constrained by the requirement for mm-size crystals for many problems. These limitations are being addressed through the realization of powerful instruments at a new generation of pulsed neutron sources, including in the USA the TOPAZ and MaNDi single-crystal diffractometers that are under development at the Spallation Neutron Source (SNS).

Single-crystal neutron diffraction studies of hydrogen-bonded systems: Two recent examples from IPNS

International Nuclear Information System (INIS)

Koetzle, Thomas F.; Piccoli, Paula M.B.; Schultz, Arthur J.

2009-01-01

Beginning with work in the 1950s at the first generation of research reactors, studies of hydrogen-bonded systems have been a prime application for single-crystal neutron diffraction. The range of systems studied was extended in the 1960s and 1970s, with the advent of high flux reactor sources, and beginning around 1980 studies at pulsed neutron sources have made increasingly important contributions. Recently at the Argonne Intense Pulsed Neutron Source (IPNS), working with collaborators, we completed two studies of hydrogen-bonded systems that will serve to illustrate topics of current interest. In the first study, on andrographolide, an active diterpenoid natural product, our neutron diffraction results definitively characterize the hydrogen-bonding interactions. The second IPNS study is on tetraacetylethane (TAE), a β-diketone enol system with a very short, strong intramolecular O-H...O hydrogen bond. At IPNS, we have determined the neutron crystal structure of TAE at five temperatures between 20 and 298 K to investigate changes in the structure with temperature and to probe for disorder. Despite the successes illustrated by the two examples presented here and by many other studies, at present applications of single-crystal neutron diffraction continue to be extremely flux limited and constrained by the requirement for mm-size crystals for many problems. These limitations are being addressed through the realization of powerful instruments at a new generation of pulsed neutron sources, including in the USA the TOPAZ and MaNDi single-crystal diffractometers that are under development at the Spallation Neutron Source (SNS).

Conceptual design of the HTTR-IS hydrogen production system

International Nuclear Information System (INIS)

Sakaba, Nariaki; Sato, Hiroyuki; Hara, Teruo; Kato, Ryoma; Ohashi, Kazutaka; Nishihara, Tetsuo; Kunitomi, Kazuhiko

2007-08-01

Since hydrogen produced by nuclear should be economically competitive compared with other methods in a hydrogen society, it is important to build hydrogen production system to be coupled with the reactor as a conventional chemical plant. Japan Atomic Energy Agency started the safety study to establish a new safety philosophy to meet safety requirements for non-nuclear grade hydrogen production system. Also, structural concepts with integrating functions for the Bunsen reactor and sulphuric acid decomposer were proposed to reduce construction cost of the IS process hydrogen production system. In addition, HI decomposer which enables the process condition to be eased consisting of conventional materials and technologies was studied. Moreover, technical feasibility of the HTTR-IS system in which the hydrogen production rate of 1,000 Nm 3 /h by using the supplied heat of 10 MW from the intermediate heat exchanger of the HTTR was confirmed. This paper describes the conceptual design of the HTTR-IS hydrogen production system. (author)

Leak detection in Phenix and Super Phenix steam generators

Energy Technology Data Exchange (ETDEWEB)

Cambillard, E [Centre d' Etudes Nucleaires de Saclay, Gif-sur-Yvette (France)

1978-10-01

Water leak detection Phenix and Super Phenix steam generators is based on measurement of the hydrogen produced by the reaction of sodium with water. The hydrogen evolves in the sodium in which the steam generator tubes are completely immersed. Depending on service conditions, however (sodium temperature and flow velocity), the hydrogen may appear in the argon existing above the free levels. This is why, although the Phenix steam generators do not feature free levels, measurement systems were added to measure the hydrogen concentration in the argon in the expansion tanks. Super Phenix steam generators are fitted at their outlet with systems for measuring hydrogen in the sodium, and above their free level with a system for measuring hydrogen in the argon. The measurement systems have nickel tube probes connected to circuits kept under vacuum by an ion pump. The hydrogen partial pressure is measured by a mass spectrometer. Super Phenix measurement systems differ from Phenix systems essentially in the temperature regulation of the sodium reaching the nickel tube probes, and in the centralization of the supply and measurement systems of the ion pumps and mass spectrometers. This paper deals with description, calibration and operating conditions of the hydrogen detection systems in sodium and argon in Phenix and Super Phenix steam generators. (author)

Research and development of HTTR hydrogen production systems

International Nuclear Information System (INIS)

Shiozawa, Shusaku; Ogawa, Masuro; Inagaki, Yoshiyuki; Onuki, Kaoru; Takeda, Tetsuaki; Nishihara, Tetsuo; Hayashi, Koji; Kubo, Shinji; Inaba, Yoshitomo; Ohashi, Hirofumi

2002-01-01

The Japan Atomic Energy Research Institute (JAERI) has constructed the High Temperature Engineering Test Reactor (HTTR) with a thermal output of 30MW and a reactor out let coolant temper at ure of 950 .deg. C. There search and development (R and D) program on nuclear production of hydrogen was started on January in 1997 as a study consigned by Ministry of Education, Culture, Sports, Science and Technology. A hydrogen production system connected to the HTTR is being designed to be able to produce hydrogen of about 4000m 3 /h by steam reforming of natural gas, using a nuclear heat of 10MW supplied by the HTTR hydrogen production system. In order to confirm controllability, safety and performance of key components in the HTTR hydrogen production system, the facility for the out-of-pile test was constructed on the scale of approximately 1/30 of the HTTR hydrogen production system. In parallel to the out-of-pile test, the following tests as essential problem, a corrosion test of a reforming tube, a permeation test of hydrogen isotopes through heat exchanger and reforming tubes, and an integrity test of a high-temperature isolation valve are carried out to obtain detailed data for safety review and development of analytical codes. Other basis studies on the hydrogen production technology of thermochemical water splitting called an iodine sulfur (IS) process, has been carried out for more effective and various uses of nuclear heat. This paper describes the present status and a future plan on the R and D of the HTTR hydrogen production systems in JAERI

Hydrogen Storage Technologies for Future Energy Systems.

Science.gov (United States)

Preuster, Patrick; Alekseev, Alexander; Wasserscheid, Peter

2017-06-07

Future energy systems will be determined by the increasing relevance of solar and wind energy. Crude oil and gas prices are expected to increase in the long run, and penalties for CO 2 emissions will become a relevant economic factor. Solar- and wind-powered electricity will become significantly cheaper, such that hydrogen produced from electrolysis will be competitively priced against hydrogen manufactured from natural gas. However, to handle the unsteadiness of system input from fluctuating energy sources, energy storage technologies that cover the full scale of power (in megawatts) and energy storage amounts (in megawatt hours) are required. Hydrogen, in particular, is a promising secondary energy vector for storing, transporting, and distributing large and very large amounts of energy at the gigawatt-hour and terawatt-hour scales. However, we also discuss energy storage at the 120-200-kWh scale, for example, for onboard hydrogen storage in fuel cell vehicles using compressed hydrogen storage. This article focuses on the characteristics and development potential of hydrogen storage technologies in light of such a changing energy system and its related challenges. Technological factors that influence the dynamics, flexibility, and operating costs of unsteady operation are therefore highlighted in particular. Moreover, the potential for using renewable hydrogen in the mobility sector, industrial production, and the heat market is discussed, as this potential may determine to a significant extent the future economic value of hydrogen storage technology as it applies to other industries. This evaluation elucidates known and well-established options for hydrogen storage and may guide the development and direction of newer, less developed technologies.

Detail Design of the hydrogen system and the gas blanketing system for the HANARO-CNS

International Nuclear Information System (INIS)

Choi, Jung Woon; Kim, Hark Rho; Kim, Young Ki; Wu, Sang Ik; Kim, Bong Su; Lee, Yong Seop

2007-04-01

The cold neutron source (CNS), which will be installed in the vertical CN hole of the reflector tank at HANARO, makes thermal neutrons to moderate into the cold neutrons with the ranges of 0.1 ∼ 10 meV passing through a moderator at about 22K. A moderator to produce cold neutrons is liquid hydrogen, which liquefies by the heat transfer with cryogenic helium flowing from the helium refrigeration system (HRS). Because of its installed location, the hydrogen system is designed to be surrounded by the gas blanketing system to notify the leakage on the system and to prevent hydrogen leakage out of the CNS. The hydrogen system, consisted of hydrogen charging unit, hydrogen storage unit, hydrogen buffer tank, and hydrogen piping, is designed to smoothly and safely supply hydrogen to and to draw back hydrogen from the IPA of the CNS under the HRS operation mode. Described is that calculation for total required hydrogen amount in the CNS as well as operation schemes of the hydrogen system. The gas blanketing system (GBS) is designed for the supply of the compressed nitrogen gas into the air pressurized valves for the CNS, to isolate the hydrogen system from the air and the water, and to prevent air or water intrusion into the vacuum system as well as the hydrogen system. All detail descriptions are shown inhere as well as the operation scheme for the GBS

Hydrogen Production from Optimal Wind-PV Energies Systems

Energy Technology Data Exchange (ETDEWEB)

Tafticht, T.; Agbossou, K. [Institut de recherche sur l hydrogene, Universite du Quebec - Trois-Rivieres, C.P. 500, Trois-Rivieres, (Ciheam), G9A 5H7, (Canada)

2006-07-01

Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyser, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

Hydrogen Production from Optimal Wind-PV Energies Systems

International Nuclear Information System (INIS)

T Tafticht; K Agbossou

2006-01-01

Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyzer, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

Hydrogen Production from Optimal Wind-PV Energies Systems

International Nuclear Information System (INIS)

Tafticht, T.; Agbossou, K.

2006-01-01

Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyser, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

Hydrogen Production from Optimal Wind-PV Energies Systems

Energy Technology Data Exchange (ETDEWEB)

T Tafticht; K Agbossou [Institut de recherche sur l hydrogene, Universite du Quebec - Trois-Rivieres, C.P. 500, Trois-Rivieres, (Ciheam), G9A 5H7, (Canada)

2006-07-01

Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyzer, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

HNEI wind-hydrogen program

International Nuclear Information System (INIS)

Neill, D.; Holst, B.; Yu, C.; Huang, N.; Wei, J.

1990-01-01

This paper reports on wind powered hydrogen production which is promising for Hawaii because Hawaii's wind energy potential exceeds the state's current electrical energy requirements by more than twenty-fold. Wind energy costs are now approaching $0.06 to $0.08/kWh, and the U.S. Department of Energy has set a goal of $0.04/kWh. These conditions make wind power a good source for electrolytic production of hydrogen. HNEI's wind-hydrogen program, at the HNEI-Kahua Wind Energy Storage Test facility on the island of Hawaii, is developing energy storage and power electronic systems for intermittent wind and solar devices to provide firm power to the utility or to a stand-alone hybrid system. In mid 1990, the first wind-hydrogen production/storage/ generation system is scheduled for installation. HNEI's wind- hydrogen program will provide research, development, demonstration, and education on the great potential and benefits of hydrogen

Stuart Energy's experiences in developing 'Hydrogen Energy Station' infrastructure

International Nuclear Information System (INIS)

Crilly, B.

2004-01-01

'Full text:' With over 50 years experience, Stuart Energy is the global leader in the development, manufacture and integration of multi-use hydrogen infrastructure products that use the Company's proprietary IMET hydrogen generation water electrolysis technology. Stuart Energy offers its customers the power of hydrogen through its integrated Hydrogen Energy Station (HES) that provides clean, secure and distributed hydrogen. The HES can be comprised of five modules: hydrogen generation, compression, storage, fuel dispensing and / or power generation. This paper discusses Stuart Energy's involvement with over 10 stations installed in recent years throughout North America, Asia and Europe while examining the economic and environmental benefits of these systems. (author)

Simulation and operational assessment for a small autonomous wind-hydrogen energy system

International Nuclear Information System (INIS)

Bechrakis, D.A.; McKeogh, E.J.; Gallagher, P.D.

2006-01-01

A case study with respect to the current trends in hydrogen technology and market developments is presented in this paper. The main goal is to design an autonomous, environmentally sustainable and zero emission power system using commercially available equipment. In order to achieve the optimum cost effective solution, its limitations are defined by simulating its performance over a year. A scenario is chosen which is representative of an area with significant wind potential, where the grid connection is relatively long or the construction of the line itself would irretrievably harm the environment. This study simulated the operation of a small, remote hotel primarily powered by a wind turbine and supported by a hydrogen energy system incorporating a medium pressure electrolyzer, a compressed hydrogen gas storage unit and a PEM fuel cell stack. The simulated load is biased towards a particular season as in the case of a small hotel for summer holidays. This arrangement takes advantage of the long period of low load during the 'off peak' season, which enables the production of reserves of hydrogen to supplement the wind generated electricity during the 'peak' season, avoiding the use of a large electrolyzer system, which is the most expensive and vulnerable component. The simulation results showed that for this particular system, a wind turbine rated at four times the peak load power associated with the optimum combination of an electrolyzer and a hydrogen storage unit would meet the electrical energy needs of a 10 bedroom, non-luxury hotel under the supervision of a load management controller

21st century's energy: hydrogen energy system

International Nuclear Information System (INIS)

Veziroglu, T. N.

2007-01-01

Fossil fuels (i.e., petroleum, natural gas and coal), which meet most of the world's energy demand today, are being depleted fast. Also, their combustion products are causing the global problems, such as the greenhouse effect, ozone layer depletion, acid rains and pollution, which are posing great danger for our environment and eventually for the life in our planet. Many engineers and scientists agree that the solution to these global problems would be to replace the existing fossil fuel system by the Hydrogen Energy System. Hydrogen is a very efficient and clean fuel. Its combustion will produce no greenhouse gases, no ozone layer depleting chemicals, little or no acid rain ingredients and pollution. Hydrogen, produced from renewable energy (e.g., solar) sources, would result in a permanent energy system, which we would never have to change. However, there are other energy systems proposed for the post-petroleum era, such as a synthetic fossil fuel system. In this system, synthetic gasoline and synthetic natural gas will be produced using abundant deposits of coal. In a way, this will ensure the continuation of the present fossil fuel system. The two possible energy systems for the post-fossil fuel era (i.e., the solar hydrogen energy system and the synthetic fossil fuel system) are compared with the present fossil fuel system by taking into consideration production costs, environmental damages and utilization efficiencies. The results indicate that the solar hydrogen energy system is the best energy system to ascertain a sustainable future, and it should replace the fossil fuel system before the end of the 21st Century

21st Century's energy: Hydrogen energy system

International Nuclear Information System (INIS)

Veziroglu, T. Nejat; Sahin, Suemer

2008-01-01

Fossil fuels (i.e., petroleum, natural gas and coal), which meet most of the world's energy demand today, are being depleted fast. Also, their combustion products are causing the global problems, such as the greenhouse effect, ozone layer depletion, acid rains and pollution, which are posing great danger for our environment and eventually for the life in our planet. Many engineers and scientists agree that the solution to these global problems would be to replace the existing fossil fuel system by the hydrogen energy system. Hydrogen is a very efficient and clean fuel. Its combustion will produce no greenhouse gases, no ozone layer depleting chemicals, little or no acid rain ingredients and pollution. Hydrogen, produced from renewable energy (e.g., solar) sources, would result in a permanent energy system, which we would never have to change. However, there are other energy systems proposed for the post-petroleum era, such as a synthetic fossil fuel system. In this system, synthetic gasoline and synthetic natural gas will be produced using abundant deposits of coal. In a way, this will ensure the continuation of the present fossil fuel system. The two possible energy systems for the post-fossil fuel era (i.e., the solar-hydrogen energy system and the synthetic fossil fuel system) are compared with the present fossil fuel system by taking into consideration production costs, environmental damages and utilization efficiencies. The results indicate that the solar-hydrogen energy system is the best energy system to ascertain a sustainable future, and it should replace the fossil fuel system before the end of the 21st century

Borazine-boron nitride hybrid hydrogen storage system

Science.gov (United States)

Narula, Chaitanya K [Knoxville, TN; Simonson, J Michael [Knoxville, TN; Maya, Leon [Knoxville, TN; Paine, Robert T [Albuquerque, NM

2008-04-22

A hybrid hydrogen storage composition includes a first phase and a second phase adsorbed on the first phase, the first phase including BN for storing hydrogen by physisorption and the second phase including a borazane-borazine system for storing hydrogen in combined form as a hydride.

Hydrogen - From hydrogen to energy production

International Nuclear Information System (INIS)

Klotz, Gregory

2005-01-01

More than a century ago, Jules Verne wrote in 'The Mysterious Island' that water would one day be employed as fuel: 'Hydrogen and oxygen, which constitute it, used singly or together, will furnish an inexhaustible source of heat and light'. Today, the 'water motor' is not entirely the dream of a writer. Fiction is about to become fact thanks to hydrogen, which can be produced from water and when burned in air itself produces water. Hydrogen is now at the heart of international research. So why do we have such great expectations of hydrogen? 'Hydrogen as an energy system is now a major challenge, both scientifically and from an environmental and economic point of view'. Dominated as it is by fossil fuels (oil, gas and coal), our current energy system has left a dual threat hovering over our environment, exposing the planet to the exhaustion of its natural reserves and contributing to the greenhouse effect. If we want sustainable development for future generations, it is becoming necessary to diversify our methods of producing energy. Hydrogen is not, of course, a source of energy, because first it has to be produced. But it has the twofold advantage of being both inexhaustible and non-polluting. So in the future, it should have a very important role to play. (author)

System Evaluation and Economic Analysis of a HTGR Powered High-Temperature Electrolysis Hydrogen Production Plant

International Nuclear Information System (INIS)

McKellar, Michael G.; Harvego, Edwin A.; Gandrik, Anastasia A.

2010-01-01

A design for a commercial-scale high-temperature electrolysis (HTE) plant for hydrogen production has been developed. The HTE plant is powered by a high-temperature gas-cooled reactor (HTGR) whose configuration and operating conditions are based on the latest design parameters planned for the Next Generation Nuclear Plant (NGNP). The current HTGR reference design specifies a reactor power of 600 MWt, with a primary system pressure of 7.0 MPa, and reactor inlet and outlet fluid temperatures of 322 C and 750 C, respectively. The power conversion unit will be a Rankine steam cycle with a power conversion efficiency of 40%. The reference hydrogen production plant operates at a system pressure of 5.0 MPa, and utilizes a steam-sweep system to remove the excess oxygen that is evolved on the anode (oxygen) side of the electrolyzer. The overall system thermal-to-hydrogen production efficiency (based on the higher heating value of the produced hydrogen) is 40.4% at a hydrogen production rate of 1.75 kg/s and an oxygen production rate of 13.8 kg/s. An economic analysis of this plant was performed with realistic financial and cost estimating assumptions. The results of the economic analysis demonstrated that the HTE hydrogen production plant driven by a high-temperature helium-cooled nuclear power plant can deliver hydrogen at a cost of $3.67/kg of hydrogen assuming an internal rate of return, IRR, of 12% and a debt to equity ratio of 80%/20%. A second analysis shows that if the power cycle efficiency increases to 44.4%, the hydrogen production efficiency increases to 42.8% and the hydrogen and oxygen production rates are 1.85 kg/s and 14.6 kg/s respectively. At the higher power cycle efficiency and an IRR of 12% the cost of hydrogen production is $3.50/kg.

Efficiency of hydrogen gas production in a stand-alone solar hydrogen system

International Nuclear Information System (INIS)

Singh, K.; Tamakloe, R.Y.

2003-01-01

Many photovoltaic systems operate in a decentralised electricity producing system, or stand-alone mode and the total energy demand is met by the output of the photovoltaic array. The output of the photovoltaic system fluctuates and is unpredictable for many applications making some forms of energy storage system necessary. The role of storage medium is to store the excess energy produced by the photovoltaic arry, to absorb momentary power peaks and to supply energy during sunless periods. One of the storage modes is the use of electrochemical techniques, with batteries and water electrolysis as the most important examples. The present study includes three main parts: the first one is the hydrogen production form the electrolysis of water depending on the DC output current of the photovoltaic (PV) energy source and the charging of the battery. The second part presents the influence of various parameters on the efficiency of hydrogen gas production. The final part includes simulation studies with focus on solar hydrogen efficiency under the influence of various physical and chemical parameters. For a 50W panel-battery-electrolyser system, the dependence of volume of hydrogen gas on voltage, current and power yielded a maximum efficiency of 13.6% (author)

Coupling a PEM fuel cell and the hydrogen generation from aluminum waste cans

Energy Technology Data Exchange (ETDEWEB)

Martinez, Susana Silva; Albanil Sanchez, Loyda; Alvarez Gallegos, Alberto A. [Centro de Investigacion en Ingenieria y Ciencias Aplicadas, Av. Universidad 1001, Col. Chamilpa, Cuernavaca, Mor. CP 62210 (Mexico); Sebastian, P.J. [Centro de Investigacion en Energia-UNAM, 62580 Temixco, Morelos (Mexico); Cuerpo Academico de Energia y Sustentabilidad, UPCH, Tuxtla Gutierrez, Chiapas (Mexico)

2007-10-15

High purity hydrogen was generated from the chemical reaction of aluminum and sodium hydroxide. The aluminum used in this study was obtained from empty soft drink cans and treated with concentrated sulfuric acid to remove the paint and plastic film. One gram of aluminum was reacted with a solution of 2moldm{sup -3} of sodium hydroxide to produce hydrogen. The hydrogen produced from aluminum cans and oxygen obtained from a proton exchange membrane electrolyzer or air, was fed to a proton exchange membrane (PEM) fuel cell to produce electricity. Yields of 44 mmol of hydrogen contained in a volume of 1.760dm{sup 3} were produced from one gram of aluminum in a time period of 20 min. (author)

Development of a solar-hydrogen hybrid energy system

International Nuclear Information System (INIS)

Sebastian, P.J.; Gamboa, S.A.; Vejar, Set; Campos, J.

2009-01-01

Full text: The details of the development of a PV-hydrogen hybrid energy system is presented. An arrangement of photovoltaic modules (125 W/module) was established to provide 9 kW installed power in a three-phase configuration at 127 Vrms/phase. A 5 kW fuel cell system (hydrogen/oxygen) operate as a dynamic backup of the photovoltaic system. The autonomous operation of the hybrid power system implies the production of hydrogen by electrolysis. The hydrogen is produced by water electrolysis using an electrolyzer of 1 kW power. The electrical energy used to produce hydrogen is supplied from solar panels by using 1kW of photovoltaic modules. The photovoltaic modules are installed in a sun-tracker arrangement for increasing the energy conversion efficiency. The hydrogen is stored in solar to electric commercial metal hydride based containers and supplied to the fuel cell. The hybrid system is monitored by internet and some dynamic characteristics such as demanding power, energy and power factor could be analyzed independently from the system. Some energy saving recommendations has been implemented as a pilot program at CIE-UNAM to improve the efficient use of clean energy in normal operating conditions in offices and laboratories. (author)

NaBH4 (sodium borohydride) hydrogen generator with a volume-exchange fuel tank for small unmanned aerial vehicles powered by a PEM (proton exchange membrane) fuel cell

International Nuclear Information System (INIS)

Kim, Taegyu

2014-01-01

A proton exchange membrane fuel cell system integrated with a NaBH 4 (sodium borohydride) hydrogen generator was developed for small UAVs (unmanned aerial vehicles). The hydrogen generator was composed of a catalytic reactor, liquid pump and volume-exchange fuel tank, where the fuel and spent fuel exchange the volume within a single fuel tank. Co–B catalyst supported on a porous ceramic material was used to generate hydrogen from the NaBH 4 solution. Considering the power consumption according to the mission profile of a UAV, the power output of the fuel cell and auxiliary battery was distributed passively as an electrical load. A blended wing-body was selected considering the fuel efficiency and carrying capability of fuel cell components. First, the fuel cell stack and hydrogen generator were evaluated under the operating conditions, and integrated into the airframe. The ground test of the complete fuel cell UAV was performed under a range of load conditions. Finally, the fuel cell powered flight test was made for 1 h. The volume-exchange fuel tank minimized the fuel sloshing and the change in center of gravity due to fuel consumption during the flight, so that much stable operation of the fuel cell system was validated at different flight modes. - Highlights: • PEMFC system with a NaBH 4 hydrogen source was developed for small UAVs. • Volume-exchange fuel tank was used to reduce the size of the fuel cell system. • Passive power management was used for a stable power output during the flight. • BWB UAV was selected by taking the fuel cell integration into consideration. • Stable operation of the fuel cell system was verified from the flight test

The role of hydrogen in high wind energy penetration electricity systems: the Irish case

International Nuclear Information System (INIS)

Gonzalez, A.; McKeogh, E.; Gallachoir, B.O.

2004-01-01

The deployment of wind energy is constrained by wind uncontrollability, which poses operational problems on the electricity supply system at high penetration levels, lessening the value of wind-generated electricity to a significant extent. This paper studies the viability of hydrogen production via electrolysis using wind power that cannot be easily accommodated on the system. The potential benefits of hydrogen and its role in enabling a large penetration of wind energy are assessed, within the context of the enormous wind energy resource in Ireland. The exploitation of this wind resource may in the future give rise to significant amounts of surplus wind electricity, which could be used to produce hydrogen, the zero-emissions fuel that many experts believe will eventually replace fossil fuels in the transport sector. In this paper the operation of a wind powered hydrogen production system is simulated and optimised. The results reveal that, even allowing for significant cost-reductions in electrolyser and associated balance-of-plant equipment, low average surplus wind electricity cost and a high hydrogen market price are also necessary to achieve the economic viability of the technology. These conditions would facilitate the installation of electrolysis units of sufficient capacity to allow an appreciable increase in installed wind power in Ireland. The simulation model was also used to determine the CO 2 abatement potential associated with the wind energy/hydrogen production. (author)

Solar Hydrogen Reaching Maturity

Directory of Open Access Journals (Sweden)

Rongé Jan

2015-09-01

Full Text Available Increasingly vast research efforts are devoted to the development of materials and processes for solar hydrogen production by light-driven dissociation of water into oxygen and hydrogen. Storage of solar energy in chemical bonds resolves the issues associated with the intermittent nature of sunlight, by decoupling energy generation and consumption. This paper investigates recent advances and prospects in solar hydrogen processes that are reaching market readiness. Future energy scenarios involving solar hydrogen are proposed and a case is made for systems producing hydrogen from water vapor present in air, supported by advanced modeling.

Technical Assessment of Cryo-Compressed Hydrogen Storage Tank Systems for Automotive Applications

Energy Technology Data Exchange (ETDEWEB)

Ahluwalia, Rajesh [Argonne National Lab. (ANL), Argonne, IL (United States); Hua, T. Q. [Argonne National Lab. (ANL), Argonne, IL (United States); Peng, J. -K. [Argonne National Lab. (ANL), Argonne, IL (United States); Lasher, S. [TIAX LLC, Lexington, MA (United States); McKenney, Kurtis [TIAX LLC, Lexington, MA (United States); Sinha, J. [TIAX LLC, Lexington, MA (United States)

2009-12-01

Technical report describing DOE's second assessment report on a third generation (Gen3) system capable of storing hydrogen at cryogenic temperatures within a pressure vessel on-board a vehicle. The report includes an overview of technical progress to date, including the potential to meet DOE onboard storage targets, as well as independent reviews of system cost and energy analyses of the technology paired with delivery costs.

Development of the Raman lidar system for remote hydrogen gas detection

Energy Technology Data Exchange (ETDEWEB)

Choi, In Young; Baik, Sung Hoon; Park, Seung Kyu; Park, Nak Gyu; Choi, Young Soo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

Detection of hydrogen (H{sub 2}) gas leakage is very important for safety of the nuclear power plant because H{sub 2} gas is very flammable and explosive. H{sub 2} gas is generated by oxidizing the nuclear fuel cladding during the critical accident and generated H{sub 2} gas leads to serious secondary damages in the containment building of nuclear power plant. Thus, various H{sub 2} gas detection techniques are used in the nuclear power plant such as catalytic combustion sensors, semiconducting oxide sensors, thermal conductivity sensors and electrochemical sensor. A Raman lidar (Light Detection And Ranging) system for remote detection of the H{sub 2} gas can cover the area in the containment building of a nuclear power plant. H{sub 2} gas has a very strong Raman Effect, and H{sub 2} Raman cells have been widely used for laser wavelength conversion. In this study, Raman lidar system was developed for H{sub 2} gas detection used in the containment building of nuclear power plant. In this study, remote hydrogen gas detection devices and measuring algorithm are developed by using the Raman lidar method. Through the experiment, we proved that our developed Raman lidar system was possible to measure the N{sub 2} and H{sub 2} gas scattering signal remotely.

Dibenzothiophene hydrodesulfurization over Ru promoted alumina based catalysts using in situ generated hydrogen

International Nuclear Information System (INIS)

Muhammad, Yaseen; Lu Yingzhou; Shen Chong; Li Chunxi

2011-01-01

Catalytic hydrodesulfurization (HDS) of dibenzothiophene (DBT) was carried out in a temperature range of 320-400 o C using in situ generated hydrogen coupled with the effect of selected organic additives for the first time. Four kinds of alumina based catalysts i.e. Co-Mo/Al 2 O 3 , Ni-Mo/Al 2 O 3 , Ru-Co-Mo/Al 2 O 3 and Ru-Ni-Mo/Al 2 O 3 were used for the desulfurization process, which were prepared following incipient impregnation method with fixed metal loadings (wt.%) of Co, Ni, Mo and Ru. The surface area, average pore diameter and pore volume distribution of the fresh and used catalysts were measured by N 2 adsorption using BET method. Catalytic activity was investigated in a batch autoclave reactor in the complete absence of external hydrogen gas. Addition and mutual reaction of specific quantities of water and ethanol provided the necessary in situ hydrogen for the desulfurization reaction. Organic additives like diethylene glycol (DEG), phenol, naphthalene, anthracene, o-xylene, tetralin, decalin and pyridine did impinge the HDS activity of the catalysts in different ways. Liquid samples from reaction products were quantitatively analyzed by HPLC technique while qualitative analyses were made using GC-MS. Both of these techniques showed that Ni-based catalysts were more active than Co-based ones at all conditions. Moreover, incorporation of Ru to both Co and Ni-based catalysts greatly promoted desulfurization activity of these catalysts. DBT conversion of up to 84% was achieved with Ru-Ni-Mo/Al 2 O 3 catalyst at 380 o C temperature for 11 h. Catalyst systems followed the HDS activity order as: Ru-Ni-Mo/Al 2 O 3 > Ni-Mo/Al 2 O 3 > Ru-Co-Mo/Al 2 O 3 > Co-Mo/Al 2 O 3 at all conditions. Cost effectiveness, mild operating conditions and reasonably high catalytic activity using in situ generated hydrogen mechanism proved our process to be useful for HDS of DBT.

Investigation of a hydrogen mitigation system during large break loss-of-coolant accident for a two-loop pressurized water reactor

Energy Technology Data Exchange (ETDEWEB)

Dehjourian, Mehdi; Rahgoshay, Mohmmad; Jahanfamia, Gholamreza [Dept. of Nuclear Engineering, Science and Research Branch, Islamic Azad University of Tehran, Tehran (Iran, Islamic Republic of); Sayareh, Reza [Faculty of Electrical and Computer Engineering, Kerman Graduate University of Technology, Kerman (Iran, Islamic Republic of); Shirani, Amir Saied [Faculty of Engineering, Shahid Beheshti University, Tehran (Iran, Islamic Republic of)

2016-10-15

Hydrogen release during severe accidents poses a serious threat to containment integrity. Mitigating procedures are necessary to prevent global or local explosions, especially in large steel shell containments. The management of hydrogen safety and prevention of over-pressurization could be implemented through a hydrogen reduction system and spray system. During the course of the hypothetical large break loss-of-coolant accident in a nuclear power plant, hydrogen is generated by a reaction between steam and the fuel-cladding inside the reactor pressure vessel and also core concrete interaction after ejection of melt into the cavity. The MELCOR 1.8.6 was used to assess core degradation and containment behavior during the large break loss-of-coolant accident without the actuation of the safety injection system except for accumulators in Beznau nuclear power plant. Also, hydrogen distribution in containment and performance of hydrogen reduction system were investigated.

Production of Hydrogen from Bio-ethanol

International Nuclear Information System (INIS)

Fabrice Giroudiere; Christophe Boyer; Stephane His; Robert Sanger; Kishore Doshi; Jijun Xu

2006-01-01

IFP and HyRadix are collaborating in the development of a new hydrogen production system from liquid feedstock such as bio-ethanol. Reducing greenhouse gas (GHG) emissions along with high hydrogen yield are the key objectives. Market application of the system will be hydrogen refueling stations as well as medium scale hydrogen consumers including the electronics, metals processing, and oils hydrogenation industries. The conversion of bio-ethanol to hydrogen will be performed within a co-developed process including an auto-thermal reformer working under pressure. The technology will produce high-purity hydrogen with ultralow CO content. The catalytic auto-thermal reforming technology combines the exothermic and endothermic reaction and leads to a highly efficient heat integration. The development strategy to reach a high hydrogen yield target with the bio-ethanol hydrogen generator is presented. (authors)

Workshop on Hydrogen Storage and Generation for Medium-Power and -Energy Applications

National Research Council Canada - National Science Library

Matthews, Michael

1998-01-01

This report summarizes the Workshop on Hydrogen Storage and Generation Technologies for Medium-Power and -Energy Applications which was held on April 8-10, 1997 at the Radisson Hotel Orlando Airport in Orlando, Florida...

Nitric-glycolic flowsheet testing for maximum hydrogen generation rate

Energy Technology Data Exchange (ETDEWEB)

Martino, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Newell, J. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Williams, M. S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-03-01

The Defense Waste Processing Facility (DWPF) at the Savannah River Site is developing for implementation a flowsheet with a new reductant to replace formic acid. Glycolic acid has been tested over the past several years and found to effectively replace the function of formic acid in the DWPF chemical process. The nitric-glycolic flowsheet reduces mercury, significantly lowers the chemical generation of hydrogen and ammonia, allows purge reduction in the Sludge Receipt and Adjustment Tank (SRAT), stabilizes the pH and chemistry in the SRAT and the Slurry Mix Evaporator (SME), allows for effective adjustment of the SRAT/SME rheology, and is favorable with respect to melter flammability. The objective of this work was to perform DWPF Chemical Process Cell (CPC) testing at conditions that would bound the catalytic hydrogen production for the nitric-glycolic flowsheet.

Biological Hydrogen Production from Corn-Syrup Waste Using a Novel System

Directory of Open Access Journals (Sweden)

George Nakhla

2009-06-01

Full Text Available The reported patent-pending system comprises a novel biohydrogen reactor with a gravity settler for decoupling of SRT from HRT. The biohydrogenator was operated for 100 days at 37 °C, hydraulic retention time 8 h and solids retention time ranging from 2.2–2.5 days. The feed was a corn-syrup waste generated as a byproduct from an industrial facility for bioethanol production located in southwestern Ontario, Canada. The system was initially started up with a synthetic feed containing glucose at concentration of 8 g/L and other essential inorganics. Anaerobicaly-digested sludge from the St. Mary’s wastewater treatment plant (St. Mary, Ontario, Canada was used as the seed, and was heat treated at 70 °C for 30 min to inhibit methanogens. After 10 days, when the hydrogen production was steady, the corn-syrup waste was introduced to the system. Glucose was the main constituent in the corn-syrup; its concentration was varied over a period of 90 days from 8 to 25 g/L. The change in glucose concentration was used to study the impact of variable organic loading on the stability of hydrogen production in the biohydrogenator. Hydrogen production rate increased from 10 L H2/L·d to 34 L H2/L·d with the increase of organic loading rate (OLR from 26 to 81 gCOD/L·d, while a maximum hydrogen yield of 430 mL H2/gCOD was achieved in the system with an overall average of 385 mL H2/gCOD.

High and rapid hydrogen release from thermolysis of ammonia borane near PEM fuel cell operating temperature

Science.gov (United States)

Varma, Arvind; Hwang, Hyun Tae; Al-Kukhun, Ahmad

2016-11-15

A system for generating and purifying hydrogen. To generate hydrogen, the system includes inlets configured to receive a hydrogen carrier and an inert insulator, a mixing chamber configured to combine the hydrogen carrier and the inert insulator, a heat exchanger configured to apply heat to the mixture of hydrogen carrier and the inert insulator, wherein the applied heat results in the generation of hydrogen from the hydrogen carrier, and an outlet configured to release the generated hydrogen. To purify hydrogen, the system includes a primary inlet to receive a starting material and an ammonia filtration subassembly, which may include an absorption column configured to absorb the ammonia into water for providing purified hydrogen at a first purity level. The ammonia filtration subassembly may also include an adsorbent member configured to adsorb ammonia from the starting material into an adsorbent for providing purified hydrogen at a second purity level.

Modeling, design and analysis of a stand-alone hybrid power generation system using solar/urine

International Nuclear Information System (INIS)

Wu, Wei; Zhou, Ya-Yan; Lin, Mu-Hsuan; Hwang, Jenn-Jiang

2013-01-01

Highlights: • The stand-alone hybrid power system is presented. • The urine-to-hydrogen processor is proposed. • Scenario analysis of the hybrid power dispatching and the urine/solar demands is investigated. • The design, modeling and optimization of the hybrid power system is addressed by Aspen Plus and Matlab. - Abstract: The urine turned to hydrogen as an energy conversion process is integrated into a stand-alone hybrid (PV/FC/battery) power generation system. The optimization and simulation of a new urine-to-hydrogen processor is evaluated in Aspen Plus environment. In our approach, the PV generator aims to reduce urine consumption and the lithium-ion battery can compensate the power gap due to the fuel processing delay. Based on prescribed patterns of solar irradiation and the daily load demand of a 30-persons classroom, scenario analyses of the hybrid power dispatching and operational feasibility is addressed

Evaluation of Nuclear Hydrogen Production System

International Nuclear Information System (INIS)

Park, Won Seok; Park, C. K.; Park, J. K. and others

2006-04-01

The major objective of this work is tow-fold: one is to develop a methodology to determine the best VHTR types for the nuclear hydrogen demonstration project and the other is to evaluate the various hydrogen production methods in terms of the technical feasibility and the effectiveness for the optimization of the nuclear hydrogen system. Both top-tier requirements and design requirements have been defined for the nuclear hydrogen system. For the determination of the VHTR type, a comparative study on the reference reactors, PBR and PBR, was conducted. Based on the analytic hierarchy process (AHP) method, a systematic methodology has been developed to compare the two VHTR types. Another scheme to determine the minimum reactor power was developed as well. Regarding the hydrogen production methods, comparison indices were defined and they were applied to the IS (Iodine-Sulfur) scheme, Westinghouse process, and the, high-temperature electrolysis method. For the HTE, IS, and MMI cycle, the thermal efficiency of hydrogen production were systematically evaluated. For the IS cycle, an overall process was identified and the functionality of some key components was identified. The economy of the nuclear hydrogen was evaluated, relative to various primary energy including natural gas coal, grid-electricity, and renewable. For the international collaborations, two joint research centers were established: NH-JRC between Korea and China and NH-JDC between Korea and US. Currently, several joint researches are underway through the research centers

Solar Hydrogen Energy Systems Science and Technology for the Hydrogen Economy

CERN Document Server

Zini, Gabriele

2012-01-01

It is just a matter of time when fossil fuels will become unavailable or uneconomical to retrieve. On top of that, their environmental impact is already too severe. Renewable energy sources can be considered as the most important substitute to fossil energy, since they are inexhaustible and have a very low, if none, impact on the environment. Still, their unevenness and unpredictability are drawbacks that must be dealt with in order to guarantee a reliable and steady energy supply to the final user. Hydrogen can be the answer to these problems. This book presents the readers with the modeling, functioning and implementation of solar hydrogen energy systems, which efficiently combine different technologies to convert, store and use renewable energy. Sources like solar photovoltaic or wind, technologies like electrolysis, fuel cells, traditional and advanced hydrogen storage are discussed and evaluated together with system management and output performance. Examples are also given to show how these systems are ...

Hydrogen Peroxide Probes Directed to Different Cellular Compartments

Science.gov (United States)

Malinouski, Mikalai; Zhou, You; Belousov, Vsevolod V.; Hatfield, Dolph L.; Gladyshev, Vadim N.

2011-01-01

Background Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells. Principal Findings Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular compartments, HyPer occurred in the reduced state in the nucleus, cytosol, peroxisomes, mitochondrial intermembrane space and mitochondrial matrix, but low levels of the oxidized form of the biosensor were also observed in each of these compartments, consistent with a low peroxide tone in mammalian cells. In contrast, HyPer was mostly oxidized in the endoplasmic reticulum. Using this system, we characterized control of hydrogen peroxide in various cell systems, such as cells deficient in thioredoxin reductase, sulfhydryl oxidases or subjected to selenium deficiency. Generation of hydrogen peroxide could also be monitored in various compartments following signaling events. Conclusions We found that HyPer can be used as a valuable tool to monitor hydrogen peroxide generated in different cellular compartments. The data also show that hydrogen peroxide generated in one compartment could translocate to other compartments. Our data provide information on compartmentalization, dynamics and homeostatic control of hydrogen peroxide in mammalian cells. PMID:21283738

Hydrogen peroxide probes directed to different cellular compartments.

Directory of Open Access Journals (Sweden)

Mikalai Malinouski

2011-01-01

Full Text Available Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells.Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular compartments, HyPer occurred in the reduced state in the nucleus, cytosol, peroxisomes, mitochondrial intermembrane space and mitochondrial matrix, but low levels of the oxidized form of the biosensor were also observed in each of these compartments, consistent with a low peroxide tone in mammalian cells. In contrast, HyPer was mostly oxidized in the endoplasmic reticulum. Using this system, we characterized control of hydrogen peroxide in various cell systems, such as cells deficient in thioredoxin reductase, sulfhydryl oxidases or subjected to selenium deficiency. Generation of hydrogen peroxide could also be monitored in various compartments following signaling events.We found that HyPer can be used as a valuable tool to monitor hydrogen peroxide generated in different cellular compartments. The data also show that hydrogen peroxide generated in one compartment could translocate to other compartments. Our data provide information on compartmentalization, dynamics and homeostatic control of hydrogen peroxide in mammalian cells.

Conception of modular hydrogen storage systems for portable applications

International Nuclear Information System (INIS)

Paladini, V.; Miotti, P.; Manzoni, G.; Ozebec, J.

2003-01-01

Hydrogen, till now the most prominent candidate as a future sustainable energy carrier, yields a gravimetric energy density three times as high as liquid hydrocarbon. Furthermore it is proven to be the most environmentally friendly fuel. Unfortunately, a few components regarding storage and tank solutions have not yet reached a technology level required for broad use. Thus, we intend to propose solutions and device concepts for both devices everyday use and space applications. This contribution assesses both state of the art of storage materials and existing technologies of power generation systems for application in portable devices. The aim of this work is to define the characteristics of a modular system, being suitable for a wide range of different devices, operating on advanced metal hydrides as the active hydrogen supply component. The concept has been studied and modelled with respect to volumes, mass and power requirements of different devices. The smallest system developed is intended to run, for example, a mobile phone. Minor tuning and straightforward scale up of this power supply module should make it suitable for general applicability in any portable device. (author)

The performance of a grid-tied microgrid with hydrogen storage and a hydrogen fuel cell stack

International Nuclear Information System (INIS)

Zhang, Linfeng; Xiang, Jing

2014-01-01

Highlights: • Two microgrids with different structure are simulated. • Their performance are comprehensively evaluated and compared. • The one with DES and a FC stack has high environmental and quality indexes. - Abstract: In a heat-power system, the use of distributed energy generation and storage not only improves system’s efficiency and reliability but also reduce the emission. This paper is focused on the comprehensive performance evaluation of a grid-tied microgrid, which consists of a PV system, a hydrogen fuel cell stack, a PEM electrolyzer, and a hydrogen tank. Electricity and heat are generated in this system, to meet the local electric and heat demands. The surplus electricity can be stored as hydrogen, which is supplied to the fuel cell stack to generate heat and power as needed. The performance of the microgrid is comprehensively evaluated and is compared with another microgrid without a fuel cell stack. As a result, the emission and the service quality in the first system are higher than those in the second one. But they both have the same overall performance

Analysis method for the design of a hydrogen mitigation system with passive autocatalytic recombiners in OPR-1000

Energy Technology Data Exchange (ETDEWEB)

Kim, C-H.; Sung, J-J.; Ha, S-J. [Korea Hydro and Nuclear Power Co. Ltd., Central Research Inst., Daejeon (Korea, Republic of); Yeo, I-S. [KEPCO Engineering and Construction Co. Ltd, Gyeonggi-do (Korea, Republic of)

2014-07-01

The importance of hydrogen safety in nuclear power plants has been emphasized especially after the Fukushima accident in Japan. A passive autocatalytic recombiner (PAR) is considered as a viable option for the mitigation of hydrogen risk because of its passive operation for hydrogen removal. This paper presents a licensed hydrogen analysis method of OPR-1000, a 1,000MWe Korea standardized pressurized water reactor with a large dry containment, to determine the capacity and locations of PARs for the design of a hydrogen mitigation system with PAR. Various accident scenarios have been adopted considering important event sequences from a combination of probabilistic methods, deterministic methods and sound engineering judgment. A MAAP 4.0.6+ with a multi-compartment model is used as an analysis tool with conservative hydrogen generation and removal models. The detailed analyses are performed for selected severe accident scenarios including sensitivity analysis with/without operations of various safety systems. The possibility of global flame acceleration (FA) and deflagration-to-detonation transient (DDT) are assessed with sigma (flame acceleration potential) and 7-lambda (DDT potential) criterion. It is concluded that the newly designed hydrogen mitigation system with twenty-four (24) PARs can effectively remove hydrogen in the containment atmosphere and prevent global FA and DDT. (author)

Energy management strategy based on short-term generation scheduling for a renewable microgrid using a hydrogen storage system

DEFF Research Database (Denmark)

Cau, Giorgo; Cocco, Daniele; Petrollese, Mario

2014-01-01

This paper presents a novel energy management strategy (EMS) to control an isolated microgrid powered by a photovoltaic array and a wind turbine and equipped with two different energy storage systems: electric batteries and a hydrogen production and storage system. In particular, an optimal...

Hydrogen production from biomass by biological systems

International Nuclear Information System (INIS)

Sharifan, H.R.; Qader, S.

2009-01-01

Hydrogen gas is seen as a future energy carrier, not involved in 'greenhouse' gas and its released energy in combustion can be converted to electric power. Biological system with low energy can produce hydrogen compared to electrochemical hydrogen production via solar battery-based water splitting which requires the use of solar batteries with high energy requirements. The biological hydrogen production occurs in microalgae and cyanobacteria by photosynthesis. They consume biochemical energy to produce molecular hydrogen. Hydrogen in some algae is an anaerobic production in the absence of light. In cyanobacteria the hydrogen production simultaneously happens with nitrogen fixation, and also catalyzed by nitrogenase as a side reaction. Hydrogen production by photosynthetic bacteria is mediated by nitrogenase activity, although hydrogenases may be active for both hydrogen production and hydrogen uptake under some conditions. Genetic studies on photosynthetic microorganisms have markedly increased in recent times, relatively few genetic engineering studies have focused on altering the characteristics of these microorganisms, particularly with respect to enhancing the hydrogen-producing capabilities of photosynthetic bacteria and cyanobacteria. (author)

Hydrogen control in the System 80+TM ALWR design

International Nuclear Information System (INIS)

Schneider, R.E.; Jacob, M.C.; Carpentino, F.L.; Wachowiak, R.M.

2004-01-01

This paper provides an assessment of the features built into the System 80 +TM Advanced Light Water Reactor (ALWR) design for controlling hydrogen concentration during a hypothetical severe accident. Although the significantly larger System 80 + containment volume serves to passively maintain the global average below detonable limits, the design incorporates a Hydrogen Mitigation System (HMS) to further reduce the local hydrogen concentration. The HMS consists of a large number of hydrogen ignitors distributed within the containment to selectively burn-off hydrogen at low concentrations. The criteria for the placement of these igniters are discussed along with an assessment of the effectiveness of the igniters to control the hydrogen concentrations. This assessment, which was performed using the generalized containment model of the MAAP 4 code, evaluated the potential for hydrogen build-up in the containment and calculated the best-estimate response of the igniters. (author)

Modeling leaks from liquid hydrogen storage systems.

Energy Technology Data Exchange (ETDEWEB)

Winters, William Stanley, Jr.

2009-01-01

This report documents a series of models for describing intended and unintended discharges from liquid hydrogen storage systems. Typically these systems store hydrogen in the saturated state at approximately five to ten atmospheres. Some of models discussed here are equilibrium-based models that make use of the NIST thermodynamic models to specify the states of multiphase hydrogen and air-hydrogen mixtures. Two types of discharges are considered: slow leaks where hydrogen enters the ambient at atmospheric pressure and fast leaks where the hydrogen flow is usually choked and expands into the ambient through an underexpanded jet. In order to avoid the complexities of supersonic flow, a single Mach disk model is proposed for fast leaks that are choked. The velocity and state of hydrogen downstream of the Mach disk leads to a more tractable subsonic boundary condition. However, the hydrogen temperature exiting all leaks (fast or slow, from saturated liquid or saturated vapor) is approximately 20.4 K. At these temperatures, any entrained air would likely condense or even freeze leading to an air-hydrogen mixture that cannot be characterized by the REFPROP subroutines. For this reason a plug flow entrainment model is proposed to treat a short zone of initial entrainment and heating. The model predicts the quantity of entrained air required to bring the air-hydrogen mixture to a temperature of approximately 65 K at one atmosphere. At this temperature the mixture can be treated as a mixture of ideal gases and is much more amenable to modeling with Gaussian entrainment models and CFD codes. A Gaussian entrainment model is formulated to predict the trajectory and properties of a cold hydrogen jet leaking into ambient air. The model shows that similarity between two jets depends on the densimetric Froude number, density ratio and initial hydrogen concentration.

Design study of the cooling scheme for SMES system in ASPCS by using liquid hydrogen

Energy Technology Data Exchange (ETDEWEB)

Makida, Yasuhiro, E-mail: yasuhiro.makida@kek.jp [High Energy Accelerator Research Organization, Oho 1-1, Tsukuba 305-0801 (Japan); Shintomi, Takakazu [Nihon University, Chiyoda-ku, Tokyo 102-8251 (Japan); Asami, Takuya; Suzuki, Goro; Takao, Tomoaki [Sophia University, Chiyoda-ku, Tokyo 102-8554 (Japan); Hamajima, Takataro [Hachinohe Institutue of Technology, Hachinohe, Aomori 031-8501 (Japan); Tsuda, Makoto; Miyagi, Daisuke [Tohoku University, Aoba-ku, Sendai 980-8579 (Japan); Munakata, Kouhei; Kajiwara, Masataka [Iwatani Corp., Minato-ku, Tokyo 104-8058 (Japan)

2013-11-15

Highlights: •Advanced Superconducting Power Conditioning System is composed of SMES, FC–EL, H{sub 2} storage. •The ASPCS is proposed to be built beside a LH{sub 2} storage of a vehicle station to effectively use the cooling capability of liquid hydrogen. •The SMES coil, which is made from an MgB{sub 2} conductor, is indirectly cooled by LH{sub 2} through its own conduction. -- Abstract: From the point of view of environment and energy problems, the renewable energies have been attracting attention. However, fluctuating power generation by the renewable energies affects the stability of the power network. Thus, we propose a new electric power storage and stabilization system, Advanced Superconducting Power Conditioning System (ASPCS), in which a Superconducting Magnetic Energy Storage (SMES) and a hydrogen-energy-storage converge on a liquid hydrogen station for fuel cell vehicles. The ASPCS proposes that the SMES coils wound with MgB{sub 2} conductor are indirectly cooled by thermo-siphon circulation of liquid hydrogen to use its cooling capability. The conceptual design of cooling scheme of the ASPCS is presented.

Design study of the cooling scheme for SMES system in ASPCS by using liquid hydrogen

International Nuclear Information System (INIS)

Makida, Yasuhiro; Shintomi, Takakazu; Asami, Takuya; Suzuki, Goro; Takao, Tomoaki; Hamajima, Takataro; Tsuda, Makoto; Miyagi, Daisuke; Munakata, Kouhei; Kajiwara, Masataka

2013-01-01

Highlights: •Advanced Superconducting Power Conditioning System is composed of SMES, FC–EL, H 2 storage. •The ASPCS is proposed to be built beside a LH 2 storage of a vehicle station to effectively use the cooling capability of liquid hydrogen. •The SMES coil, which is made from an MgB 2 conductor, is indirectly cooled by LH 2 through its own conduction. -- Abstract: From the point of view of environment and energy problems, the renewable energies have been attracting attention. However, fluctuating power generation by the renewable energies affects the stability of the power network. Thus, we propose a new electric power storage and stabilization system, Advanced Superconducting Power Conditioning System (ASPCS), in which a Superconducting Magnetic Energy Storage (SMES) and a hydrogen-energy-storage converge on a liquid hydrogen station for fuel cell vehicles. The ASPCS proposes that the SMES coils wound with MgB 2 conductor are indirectly cooled by thermo-siphon circulation of liquid hydrogen to use its cooling capability. The conceptual design of cooling scheme of the ASPCS is presented

Identification of intrinsic catalytic activity for electrochemical reduction of water molecules to generate hydrogen

KAUST Repository

Shinagawa, Tatsuya

2015-01-01

Insufficient hydronium ion activities at near-neutral pH and under unbuffered conditions induce diffusion-limited currents for hydrogen evolution, followed by a reaction with water molecules to generate hydrogen at elevated potentials. The observed constant current behaviors at near neutral pH reflect the intrinsic electrocatalytic reactivity of the metal electrodes for water reduction. This journal is © the Owner Societies.

A hydrogen refill for cellular phone

Science.gov (United States)

Prosini, Pier Paolo; Gislon, Paola

A device has been designed to generate hydrogen for a fuel cell powered cellular phone. The device is based on the chemical reaction between NaBH 4 and hydrochloric/water solution to satisfy the hydrogen request at room temperature and pressure. The operation mechanism and controlling method is based on the Kipp's gas generating apparatus. A prototype has been built and tested to evaluate the optimum salt/acid and acid/solution ratios and check the hydrogen mass flow rates upon operation and the pressure variation in stand-by condition. The system works delivering hydrogen flows ranging between 0 and 10 ml min -1. In a typical test the hydrogen flow was set to 5 ml min -1 to match a 1 W power fuel cell. The working pressure was slightly higher than the atmospheric one. The hydrogen capacity was as high as 2.5% (w/w). By converting this amount of hydrogen in electricity by a fuel cell working at 0.8 V it is possible to achieve a system energy density of about 720 Wh kg -1, four times larger than commercial high energy density lithium-ion batteries.

Contribution to the study of the uranium-hydrogen system; Contribution a l'etude du systeme uranium-hydrogene

Energy Technology Data Exchange (ETDEWEB)

Chevallier, J [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1965-01-01

Previous work on uranium-hydrogen system is reviewed. The U-H{sub 2}-UH{sub n} equilibrium is then investigated at pressures below one atmosphere, i.e. at temperatures lower than 430 deg. C. The hydride obtained at equilibrium is deficient in hydrogen (UH{sub n<3}), the hydrogen deficit increasing as the temperature rises. Thermodynamic functions for the formation of non-stoichiometric hydride and of one hydrogen vacancy are derived from pressure composition isotherms, in U-H phase diagram is proposed. The hydrogenation of U-UC alloys is also examined at pressures below one atmosphere with regard to the equilibrium: (free U + UC) - H{sub 2}-UH{sub n}. The equilibrium conditions are found different from that observed for pure uranium. (author) [French] Une etude bibliographique du systeme uranium-hydrogene est exposee. L'equilibre U-H{sub 2}-UH{sub n} est ensuite etudie sous des pressions inferieures a une atmosphere, soit aux temperatures inferieures a environ 430 degs. C. L'hydrure obtenu a l'equilibre est deficitaire en hydrogene - UH{sub n<3} - et d'autant plus que la temperature s'eleve. Les grandeurs thermodynamiques relatives a la formation et a la saturation de l'hydrure, ainsi qu'a la formation d'une lacune d'hydrogene sont deduites des pressions d'equilibre. Un modele de diagramme de phases U-H est propose. L'hyduration des alliages U-UC est etudiee egalement sous des pressions inferieures a l'atmosphere, au point de vue de l'equilibre (U libre + UC) - H{sub 2}-UH{sub n}. Les conditions d'equilibre sont trouvees differentes de celles observees sur l'uranium pur. (auteur)

Solar hydrogen hybrid system with carbon storage

International Nuclear Information System (INIS)

Zini, G.; Marazzi, R.; Pedrazzi, S.; Tartarini, P.

2009-01-01

A complete solar hydrogen hybrid system has been developed to convert, store and use energy from renewable energy sources. The theoretical model has been implemented in a dynamic model-based software environment and applied to real data to simulate its functioning over a one-year period. Results are used to study system design and performance. A photovoltaic sub-system directly drives a residential load and, if a surplus of energy is available, an electrolyzer to produce hydrogen which is stored in a cluster of nitrogen-cooled tanks filled with AX-21 activated carbons. When the power converted from the sun is not sufficient to cover load needs, hydrogen is desorbed from activated carbon tanks and sent to the fuel-cell sub-system so to obtain electrical energy. A set of sub-systems (bus-bar, buck- and boost-converters, inverter, control circuits), handle the electrical power according to a Programmable Logic Control unit so that the load can be driven with adequate Quality of Service. Hydrogen storage is achieved through physisorption (weak van der Waals interactions) between carbon atoms and hydrogen molecules occurring at low temperature (77 K) in carbon porous solids at relatively low pressures. Storage modeling has been developed using a Langmuir-Freundlich 1st type isotherm and experimental data available in literature. Physisorption storage provides safer operations along with good gravimetric (10.8% at 6 MPa) and volumetric (32.5 g/l at 6 MPa) storage capacities at costs that can be comparable to, or smaller than, ordinary storage techniques (compression or liquefaction). Several test runs have been performed on residential user data-sets: the system is capable of providing grid independence and can be designed to yield a surplus production of hydrogen which can be used to recharge electric car batteries or fill tanks for non-stationary uses. (author)