• 전기학회논문지
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• 제58권3호
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• pp.539-543
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• 2009

This paper describes the sensitivity enhancement in measurement of the hydrogen gas dissolved in oil using gas collection time. On-line gas measurement is a useful for continuous monitoring of power transformer. Recently many studies on hydrogen gas measurement, due to their simplicity and low price, have been done for transformer monitoring. In measurement of the hydrogen gas in oil, the suitable sensitivity and resolution in the desired ranges of the gas concentrations are needed for the reliable monitoring of power transformers. In this study, the sensor output trends were analyzed with the hydrogen gas collection time which means the time to collect the hydrogen gas before reaction of hydrogen gas sensor. It is indicated that the sensor outputs were increased with the increase of hydrogen gas collection times at the same hydrogen gas concentrations.

• 한국수소및신에너지학회논문집
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• 제22권4호
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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.

• 한국수소및신에너지학회논문집
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• 제17권2호
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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.

• 한국수소및신에너지학회논문집
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• 제30권3호
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• pp.251-259
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• 2019

The aim of this study is to evaluate the economic feasibility of domestic on-site steam methane reforming (SMR) hydrogen refueling stations. We evaluated the levelized cost of hydrogen (LCOH) for the SMR hydrogen refueling stations, which have production capacities of 100 kg/day (SMR 100), 200 kg/day (SMR 200), and 500 kg/day (SMR 500) utilizing the scale factor. The main results indicated that the LCOH of SMR 100, SMR 200, and SMR 500 were 14,367 won/kg, 11,122 won/kg, and 8,157 won/kg, if the utilizations of hydrogen stations were 70%. These results imply that the production capacity of the domestic SMR hydrogen station should be greater than 500 kg/day to compete with other hydrogen stations when we consider the current sale price of hydrogen at the hydrogen stations.

• 한국수소및신에너지학회논문집
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• 제33권3호
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• pp.183-201
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• 2022

In this study, economic feasibility analysis was performed when various hydrogen production and transport technologies were applied to derive hydrogen supply plans by period. The cost of hydrogen may vary depending on several reasons; configuration of the entire cycle supply path from production, storage/transportation, and utilization to the cost that can be supplied to consumers. In this analysis, the hydrogen supply price according to the hydrogen supply route configuration for each period was analyzed for the transportation hydrogen demand in metropolitan area, where the demand for hydrogen is expected to be the highest due to the expansion of hydrogen supply.

• 신재생에너지
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• 제1권3호
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• pp.42-50
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• 2005

This paper deals with the economic feasibility model and analysis of a hydrogen fuel-cell vehicle [FCV] against two similar types of non-business vehicles fueled with gasoline [GV] and diesel [DV] considering greenhouse gas [GHG]. Considering the price of vehicles and annual operating cost, we build a classical economic feasibility model. Since the economic feasibility could be affected by many input factors such as the prices of vehicles, the price of fuels, annual driving distance and so on, we estimate the average future values of input factors, which is defined as "the average case". Based on the average case, we assess the representative economic feasibility of a FCV with/without GHG, and by changing various annual driving distances, we assess its economy in terms of net-present value, internal rate of return, and payback period. In addition, we make some sensitivity analysis of its economic feasibility by changing the values of the critical input factors one at time. Based on the average case, it turns out that the consumer of a FCV could save 25,000 won/year for a GV, but the consumer could pay 120,000 won/year more for a DV. This indicates that gasoline vehicles could be replaced gradually by FCVs in Korean market which might be formed by those consumers driving annually more than approximately 14,800 km. As the results of our sensitivity analysis, it turns out that a FCV is no more economical if the difference of the prices between FCV and GV is more than 10,130,000 won or the price of hydrogen fuel could be more than 5,136 won/kg.

• 한국수소및신에너지학회논문집
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• 제23권4호
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• pp.412-419
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• 2012

Increasing demand for natural gas and higher natural gas prices in the recent decades have led many people to pursue unconventional methods of natural gas production. POSCO-Gwangyang synthetic natural gas (SNG) project was launched in 2010. As the market price of natural gas goes up, the increase of its price gets more sensitive due to the high cost of transportation and liquefaction. This project can make the SNG economically viable. In parallel with this project, KEPCO (Korea Electric Power Corporation) joined in launching the SNG Quality Standard Bureau along with KOGAS (Korea Gas Corporation), POSCO and so on. KEPCO Research Institute is in charge of SNG fueled gas turbine combustion test. In this research, several combustion tests were conducted to find out the effect of hydrogen contents in SNG on gas turbine combustion. The hydrogen in synthetic natural gas did not affect on gas turbine combustion characteristics which are turbine inlet temperature including pattern factor and emission performance. However, flame stable region in ${\Phi}$-Air flow rate map was shifted to the lean condition due to autocatalytic effect of hydrogen.

• 한국수소및신에너지학회논문집
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• 제33권6호
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• pp.660-673
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• 2022

In achieving carbon neutrality and the hydrogen economy, the estimation of H₂ cost is critical in terms of CCU technologies. This study analyzes LCOH of hydrogen produced by the carbon utilization unit with methane reforming and CO₂ from thermal power plant. LCOH for H₂ made with CO is estimated in three ways of Joint Cost Allocations with financial performance risk assessment. Regarding cost analysis, the zero value of LCOH is $6,003/ton. We found that the CCU technology has economic feasibility in terms of profitability. The sensitivity analysis result shows that the input ratio is more influential to the LCOH than other variables. Risk analysis presents the baseline price of zero value of LCOH - $8,408/ton, which is higher than the cost analysis - $6,003/ton. Mainly, the price variability of natural gas primarily affects the LCOH. The study has significant value in analyzing the financial performance risks as well as the cost of H₂ produced by a Plasma-based CCU system.

• 한국수소및신에너지학회논문집
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• 제28권3호
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• pp.279-286
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• 2017

Korea government decides to build one hundred hydrogen refueling stations (HRS) until 2020 and tries to disseminate HRS and boosts HRS market in korea. Naepo HRS in chungnam province has been operated for last one full year of 2016 and recorded 2,520 times full charge for the hydrogen fuel cell powered vehicles and total 6,016 kg hydrogen fueling for the 25 units of hydrogen fuel cell powered vehicles. Raw fuel of hydrogen from tube trailer measured by pressure, converting into weight of hydrogen and shows 19.6% surplus with final charged weight by dispenser. This result is caused measuring errors. Measured charged errors between dispenser and Mass flow meter was determined 13.13%.

• 에너지공학
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• 제16권4호
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• pp.170-180
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• 2007

본 연구에서는 증기개질 방식으로 천연가스와 납사를 연료로 하여 수소를 생산하는 국내 분산형 수소충전소의 규모의 경제성 문제를 다루었다. 분산형 수소충전소의 수소 생산규모는 $30\;Nm^3/hr,\;100\;Nm^3/hr,\;300\;Nm^3/hr$ 등을 분석대상으로 하였다. 분산형 수소충전소의 초기투자비 및 연간운영비, 수소 판매가격 등을 주요변수로 하는 전통적인 경제성 분석모형을 수립하였으며 수소 판매가격과 할인율을 대상으로 민감도 분석을 수행하였다. 천연가스를 원료로 하는 수소충전소의 수소가격은 $30\;Nm^3/hr,\;100\;Nm^3/hr,\;300\;Nm^3/hr$ 등의 생산규모에 대하여 각기 18,472원/kg, 10,686원/kg, 7,758원/kg이며, 천연가스 대신에 납사를 사용하여도 거의 비슷한 수소 가격을 갖는 것으로 추정되었다. 현 시점에서 $300\;Nm^3/hr$ 이하의 수소충전소는 경제성이 부족한 것으로 나타났으며, 이러한 경제성 분석결과는 향후에 분산형 수소충전소를 건설할 때 중대형 생산규모 이상의 수소충전소를 중심으로 보급하는 것이 바람직한 방안인 것을 시사하고 있다.