• Journal of Climate Change Research
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• v.7 no.3
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• pp.335-339
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• 2016

The purpose of this study is to analyze effects of greenhouse gas reduction in organic agriculture. To accomplish the objective of the study, a field survey was conducted. Based on the field survey results, LCA method was used to estimate the greenhouse gas emission. The farmer survey and LCA estimation data were provided by The Foundation of Agricultural Technology Commercialization and Transfer. The GHG estimation results showed that GHG emission of organic farming is less by 10.6~89.3% when compared with the conventional farming. In addition, the economic value of greenhouse gas reduction in organic farming amounts to 1,097 million won. Based on major findings, in response to national greenhouse gas reduction target, it is needed to expand organic farming, supporting organic farmers' income.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.647-650
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• 2005

Gas hydrates draw great at tent ion recently as a new clean energy resources substituting conventional oil and gas hydrate its presumed huge amount of volume reaching 10 trillion tons of gas and environmentally friendly characteristics. Gas hydrate can contribute to the rapidly increasing consumption of natural gas in Korea and achieve the self support target by 2010 which is $30\%$ of total natural gas demand. This paper shows the importance and benefit of Gas hydrate comparing with new & renewable energy in Korea

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.103-108
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• 2003

In this paper, the current lead for superconducting device is studied by numerical method. The current lead is cooled by surrounded $N_{2}$ gas by natural convection. The heat conduction equation for current lead and boundary layer equation for $N_{2}$ gas must be solved simultaneously. The boundary layer equation for $N_{2}$ gas is highly nonlinear for varied temperature of current lead. So the linearization method is adopted for simplicity. Numerical results using natural convection cooling are compared with the conventional cooling methods such as conduction cooling and vapor cooling methods. The main difference of natural convection cooing is the non-zero temperature gradient at the top of current lead for the minimum heat dissipation into superconducting devices. For the optimized conduction-cooling and vapor-cooling current leads, the temperature gradient at the top of current lead is zero. Also, the heat flow at the cold end is much smaller than conduction cooling case.

• Journal of the korean Society of Automotive Engineers
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• v.13 no.3
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• pp.49-57
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• 1991

Natural gas is one of the most promising alternative fuels for automative vehicles, because it has lower exhaust emissions and better fuel economy characteristics than gasoline and can be used in conventional engines with a little modification. In the present study, a conventional gasoline engine was modified to a CNG dedicated engine, which can be operated with CNG( compressed natural gas) only, and a engine bench test was performed at various compression ratios. As a result, it was revealed that the prototype CNG engine can be operated with lower exhaust emissions, better fuel economy and better thermal efficiency, but with a sightly reduced brake horse power, compared to the conventional gasoline engine.

• Journal of Environmental Impact Assessment
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• v.23 no.3
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• pp.227-235
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• 2014

Interest has been growing worldwide in unconventional natural gas that has become an increasingly important source of energy in the world. Unconventional gas development, including shale gas, generally involves a larger environmental impact, compared to conventional gas development, due to its intensity and scale of the operation. There are a growing number of studies on identifying and minimizing the environmental impacts of unconventional gas development. This study aims to examines the current environmental policies and regulatory systems related to the unconventional gas development. The study shows that few environmental regulation exists concerning unconventional gas development, even in the USA where unconventional gas development is most actively pursued. Regulations, however, are being developed based on studies currently underway on health and environmental risks of unconventional gas development and on guidelines designed to reduce the risks. In a world where environmental regulations are ever strengthening, review the environmental regulatory systems and guidelines about unconventional gas need to be established for Korean firms to understand environmental impacts of unconventional gas development they invest or take part in, enabling them to manage and operate gas activities in a way that minimizes environmental damages.

• Journal of the Korean Institute of Gas
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• v.19 no.2
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• pp.37-44
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• 2015

We proposed the improved Langmuir adsorption relations considering volume change effect of coal matrix during primary production of CBM and Enhanced-CBM with injection of carbon dioxide or CCS in coalseam but also volumetric strain. To verify this model, experimental data of pure gas adsorption such as $CO_2$, $CH_4$, and $N_2$ on coals were used to compare conventional Langmuir model with this model. From the results, we obtained that the larger adsorption capacity of coal and the higher adsorption affinity of gas, the larger error occur with Langmuir model. Using this model, however, we found not only substantially better fit in all condition but also reasonable volumetric strain of the coal matrix. We also applied this volume modified pure gas adsorption model to the IAS model to describe gas adsorption and volumetric strain for mixed gas. This modified-IAS model fitting experimental data by Hall et al(1994) improved accuracy of mixed gas adsorption calculation compared with conventional model.

• Journal of the Korean Institute of Gas
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• v.20 no.6
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• pp.95-101
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• 2016

For a natural gas steam reforming, comparative studies of the performance in a conventional packed-bed reactor and a membrane reactor, a new conceptual reactor consisting of a reactor with series of hydrogen separation membranes, have been performed. Based on experimental kinetics reported by Xu and Froment, a process simulation model was developed with Aspen $HYSYS^{(R)}$, a commercial process simulator, and effects of various operating conditions like temperature, $H_2$ permeance, and Ar sweep gas flow rate on the performance in a membrane reactor were investigated in terms of reactant conversion and $H_2$ yield enhancement showing improved $H_2$ yield and methane conversion in a membrane reactor. In addition, a preliminary cost estimation focusing on natural gas consumption to supply heat required for the system was carried out and feasibility of possible cost savings in a membrane reactor was assessed with a cost saving of 10.94% in a membrane reactor.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.600-603
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• 2005

U.S. National Research Council proposed benefits framework for energy R&D project as economic benefits, environmental benefits, security benefits and knowledge benefits. Following this framework, U.S. National Renewable Energy Laboratory evaluated the projected benefits of Federal Energy Efficiency and Renewable Energy Programs in the indicators of energy-expenditure savings, energy system cost savings, $CO_2$ emissions reductions. oil savings, natural gas saving and avoided additions to central conventional power. As this result, geothermal energy have predominant position in the energy-expenditure savings, natural gas saving and avoided addi t ions to central conventional power to FY2050. The projected benefits, in monetary value, of the whole supply-potential of geothermal energy in Korea were evaluated as 480.2 billion Won, 43.1 billion Won and 135.8 billion Won for the private energy-cost savings, social environmental-cost savings, and import energy-cost saving, respectively.

• Journal of the Korean Institute of Gas
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• v.19 no.6
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• pp.34-39
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• 2015

Recently, most of the energy consumed in vehicle is derived from fossil fuels. For this reason, the demand for clean, renewable and affordable alternative energy is forcing the automotive industry to look beyond the conventional fossil fuels. Natural gas represents today a promising alternative to conventional fuels for vehicles propulsion, because it is characterized by a relatively low cost, better geopolitical distribution than oil, lower environmental impact, higher octane number and a higher self ignition temperature. Above all, CNG is an environmentally clean alternative to the existing spark ignition engines with the advantages of minimum change. In this study was installed bi-fuel system that a conventional 2 liters gasoline engine was modified to run on natural gas by a gas injection system. Experiments were mainly carried on the optimization of an ECU control strategy affecting the emission characteristics of CNG/Gasoline bi-fule vehicle. The test results shown that CO2 emission in bi-fuel mode was reduced 16% compared to gasoline fuel in the NEDC mode. Also the amount of CO and HC emissions in bi-fuel and gasoline modes were found to equality. But Compared to gasoline, the bi-fuel mode resulted in higher NOx emissions.

• The Korean Journal of Petroleum Geology
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• v.7 no.1_2 s.8
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• pp.19-27
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• 1999

Korea, an energy-resources-poor country, imports $100{\%}$ of its, oil and, natural gas supply, which accounts for the greater part of its total primary requirements. One of the important task of the government is diversification of available energy resources such as oil and natural gas. Natural gas hydrate, which is non-conventional types of natural gas, distributes worldwide, especially in marine and permafrost. It would become a target of natural gas resources in the near future. Especially sigrificant amount of hydrates are expected to be located in the East Sea around Korea Peninsular. This paper describes about a multi-year overall project framework of basic research and technological development of natural gas hydrate in Korea focused on the interpretation of the seismic survey, the characteristics and physical properties of the natural gas hydrate, and the utilizable technology of natural gas hydrates from the status of research and development of the world.