• Transactions of the Korean hydrogen and new energy society
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• v.17 no.2
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• pp.218-226
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• 2006

It can be obtained from hydrocarbon and water, specially production of hydrogen from natural gas is most commercial and economical process among the hydrogen production methods, and has been used widely. However, conventional hydrogen production methods are dependent on fossil fuel such as natural gas and coal, and it may be faced with problems such as exhaustion of fossil fuels, production of greenhouse gas and increase of feedstock price. Thermochemical hydrogen production by nuclear energy has potential to efficiently produce large quantities of hydrogen without producing greenhouse gases. However, nuclear hydrogen must be economical comparing with conventional hydrogen production method. Therefore, hydrogen production cost was analyzed and estimated for nuclear hydrogen as well as conventional hydrogen production such as natural gas reforming and coal gasification in various range.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.4
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• pp.467-475
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• 2007

This study was conducted to examine temperature effects on hydrogen production in anaerobic fermentation. 18 batch reactors were operated at mesophilic ($35^{\circ}C$) and thermophilic conditions ($55^{\circ}C$) to achieve maximum hydrogen production in anaerobic fermentation. Optimum hydrogen production conditions were also investigated at each temperature. Different trends were observed regarding pH effects on hydrogen production. This effect was not significant for mesophilic fermentation ($35^{\circ}C$). In this case, pH may not drop to interfere hydrogen production during the test. However, hydrogen production decreased without pH control for thermophilic condition ($55^{\circ}C$). Effects of heat treatment were observed for both fermentation process. Hydrogen production with heat treatment was higher than hydrogen production without heat treatment for both fermentation processes. The amount of produced hydrogen for each substrate concentration with temperature changes showed that more hydrogen was produced at $35^{\circ}C$ than at $55^{\circ}C$.

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.2
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• pp.145-155
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• 2008

This paper deals with an economic evaluation of hydrogen production by fermentation. We evaluate the economic feasibility of domestic hydrogen production by fermentation utilizing glucose and waste water sludge in terms of hydrogen production prices. In addition, we make some sensitivity analysis of hydrogen prices by changing the values of input factors such as the price of glucose, the capital cost of the hydrogen production system, and the hydrogen production yields. The estimated hydrogen prices of the two-step dark-light hydrogen production by fermentation utilizing glucose was $5,347won/kgH_2$, and the single-step hydrogen production by anaerobic fermentation utilizing waste water sludge was $4,255won/kgH_2$, respectively. It is expected that the hydrogen production price by anaerobic fermentation can be reduced if we produce methane or hydrogen utilizing by-products such as alcohols and organic acids, or the government imposes some legal regulations on the treatment of waste water sludge.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.4
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• pp.559-567
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• 2011

This paper deals with an economic evaluation of domestic low-temperature water electrolysis hydrogen production. We evaluate the economic feasibility of on-site hydrogen fueling stations with the hydrogen production capacity of 30 $Nm^3/hr$ by the alkaline and the polymer electrolyte membrane water electrolysis. The hydrogen production prices of the alkaline water electrolysis, the polymer electrolyte membrane water electrolysis, and the steam methane reforming hydrogen fueling stations with the hydrogen production capacity of 30 $Nm^3/hr$ were estimated as 18,403 $won/kgH_2$, 22,945 $won/kgH_2$, 21,412 $won/kgH_2$, respectively. Domestic alkaline water electrolysis hydrogen production is evaluated as economical for small on-site hydrogen fueling stations, and we need to further study the economic evaluation of low-temperature water electrolysis hydrogen production for medium and large scale on-site hydrogen fueling stations.

• Nuclear Engineering and Technology
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• v.54 no.4
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• pp.1288-1294
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• 2022

Hydrogen as an environmentally friendly energy carrier has received special attention to solving uncertainty about the presence of renewable energy and its dependence on time and weather conditions. This material can be prepared from different sources and in various ways. In previous studies, fossil fuels have been used in hydrogen production, but due to several limitations, especially the limitation of the access to this material in the not-too-distant future and the great problem of greenhouse gas emissions during hydrogen production methods. New methods based on renewable and green energy sources as energy drivers of hydrogen production have been considered. In these methods, water or biomass materials are used as the raw material for hydrogen production. In this article, after a brief review of different hydrogen production methods concerning the required raw material, these methods are examined and ranked from different aspects of economic, social, environmental, and energy and exergy analysis sustainability. In the following, the current position of hydrogen production is discussed. Finally, according to the introduced methods, their advantages, and disadvantages, solar electrolysis as a method of hydrogen production on a small scale and hydrogen production by thermochemical method on a large scale are introduced as the preferred methods.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.723-726
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• 2009

As a preliminary study of cost estimates for nuclear hydrogen systems, the hydrogen production costs of the nuclear energy sources benchmarking GT-MHR are estimated in the necessary input data on a Korean specific basis. G4-ECONS developed by EMWG of GIF in 2008 was appropriately modified to calculate the cost for hydrogen production of SI process with VHTR as a thermal energy source rather than the LUEC. The estimated costs presented in this paper show that hydrogen production by the VHTR could be competitive with current techniques of hydrogen production from fossil fuels if $CO_2$ capture and sequestration is required. Nuclear production of hydrogen would allow large-scale production of hydrogen at economic prices while avoiding the release of $CO_2$. Nuclear production of hydrogen could thus become the enabling technology for the hydrogen economy. The major factors that would affect the cost of hydrogen were also discussed.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.1
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• pp.64-71
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• 2010

This paper deals with an economic evaluation of domestic immersing type photoelectrochemical hydrogen production. We also make some sensitivity analysis of hydrogen production prices by changing the values of input factors such as the initial capital cost, the solar to hydrogen conversion efficiency, and the system duration time. The hydrogen production price of the immersing type photoelectrochemical system was estimated as 8,264,324 won/$kgH_2$. It is expected that the production cost by photoelectrochemical hydrogen production can be reduced to 26,961 won/$kgH_2$ if the solar to hydrogen conversion efficiency is increased to 14%, the system duration time is increased to 20,000 hours, and the initial capital cost is decreased to 10% of the current level. The photoelectrochemical hydrogen production is evaluated as uneconomical at this time, and we need to enhance the solar to hydrogen conversion efficiency and the system duration time as well as to reduce prices of the system facilities.

• Transactions of the Korean hydrogen and new energy society
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• v.32 no.6
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• pp.477-482
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• 2021

Hydrogen production, hydrogen production cost, and utilization rate were calculated assuming four cases of hydrogen production system in combination of photovoltaic power generation (PV), water electrolysis system (WE), battery energy storage system (BESS), and power grid. In the case of using the PV and WE in direct connection, the smaller the capacity of the WE, the higher the capacity factor rate and the lower the hydrogen production cost. When PV and WE are directly connected, hydrogen production occurs intermittently according to time zones and seasons. In addition to the connection of PV and WE, if BESS and power grid connection are added, the capacity factor of WE can be 100%, and stable hydrogen production is possible. If BESS is additionally installed, hydrogen production cost increases due to increase in Capital Expenditures, and Operating Expenditure also increases slightly due to charging and discharging loss. Even in a hydrogen production system that connects PV and WE, linking with power grid is advantageous in terms of stable hydrogen production and improvement of capacity factor.

• Advances in Energy Research
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• v.1 no.1
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• pp.13-33
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• 2013

The present work is an attempt to provide an overview, about the status of R&D and current trends in Hydrogen Production using High Temperature Reactors. Bibliographic references from the INIS database, the Science Direct database and the NTIS database were downloaded and analyzed. Ten year data on the subject, published between 2001 and 2010, was selected for the study. Appropriate qued ry formulations on these databases, resulted in the retrieval of 621 unique bibliographic records. Using the content analysis method, all the records were analyzed. Part One of the analysis details Scientometric R&D indicators, Part Two is a subject-based analysis, grouped under: A. International Initiatives and Programmes for Hydrogen Production; B. European R&D initiatives for Hydrogen production; C. National Initiatives and Programmes for Nuclear Hydrogen Production; D. Reactor Technologies for Nuclear Hydrogen production; E. Fuel Developments; F. Hydrogen Production Processes using HTRs and G. Materials Consideration for Nuclear Hydrogen Production. The results of this analysis are summarized in the study.

• Transactions of the Korean hydrogen and new energy society
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• v.16 no.4
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• pp.391-399
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• 2005

This paper deals with the survey of domestic hydrogen production, consumption, and distribution. The amount of domestic hydrogen production and consumption has not been identified, and we survey the amount of domestic hydrogen production and consumption by industries. The hydrogen production industries are classified into the oil industry, the petrochemical industry, the chemical industry, and the other industry. In 2004, the amount of domestic hydrogen production was 972,601 ton, which corresponded to 1.9% of the global hydrogen production. The oil industry produced 635,683 ton(65.4%), the petrochemical industry produced 241,970 ton(24.9%), the chemical industry produced 66,250 ton(6.8%), the other industry produced 28,698 ton(2.9%). The hydrogen consumptions of corresponding industries were close to the hydrogen productions of industries except that of the other industry. Most hydrogen was used as non-energy for raw materials and hydrogen additions to the process. Only 122,743 ton(12.6%) of domestic hydrogen was used as energy for heating boilers. In 2004, 47,948 ton of domestic hydrogen was distributed. The market shares of pipeline, tube trailers and cylinders were 84.4% and 15.6%, respectively. The purity of 31,848 ton(66.4%) of the distributed hydrogen was 99.99%, and 16,100 ton(33.6%) was greater than or equal to 99.999%. Besides domestic hydrogen, we also identify the byproduct gases which contain hydrogen. The iron industry produces COG( coke oven gas), BFG(blast furnace gas), and LDG(Lintz Donawitz converter gas) that contain hydrogen. In 2004, byproduct gases of the iron industry contained 355,000 ton of hydrogen.