• Journal of Construction Engineering and Project Management
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• v.3 no.3
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• pp.10-16
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• 2013

The annual expenditure on diesel oil and heavy oil in the construction sector is the second largest among all industrial sectors. According to the greenhouse reduction scheme of Korean Government, construction sector targeted 7.1% reduction by 2020. Although this target is not higher than other industrial sectors, it is not easy to achieve the reduction target without radical advance in technology, which cannot be expected to happen soon, considering the conservative characteristics of construction industry. Most researches on environmental issues focus on the issues related to energy saving matters during material production stage or maintenance stage, such as heating and insulation, and few deal with the issues directly related to the energy use in the construction sites. This research regards the operation of equipment for the on-site construction processes as a system and attempts to model the energy use processes related to the activities in construction sites, and provides simulation results of earth excavation and hauling processes. The result of this research is expected to aid construction planners estimating the time-based patterns of energy use and assessing greenhouse gas emission and to help selecting more energy efficient alternatives at the planning stage.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.287-293
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• 2013

The annual expenditure on diesel oil and heavy oil in the construction sector is the second largest among all industrial sectors. According to the greenhouse reduction scheme of Korean Government, construction sector targeted 7.1% reduction by 2020. Although this target is not higher than other industrial sectors, it is not easy to achieve the reduction target without radical advance in technology, which cannot be expected to happen soon, considering the conservative characteristics of construction industry. Most researches on environmental issues focus on the issues related to energy saving matters during material production stage or maintenance stage, such as heating and insulation, and few deal with the issues directly related to the energy use in the construction sites. This research regards the operation of equipment for the on-site construction processes as a system and attempts to model the energy use processes related to the activities in construction sites, and provides simulation results of earth excavation and hauling processes. The result of this research is expected to aid construction planners estimating the time-based patterns of energy use and assessing greenhouse gas emission and to help selecting more energy efficient alternatives at the planning stage.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.7
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• pp.369-374
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• 2015

This study analyzed analyzes the energy performance of six houses in Daejeon completed which were built in 2011. Observed The observed houses, which were all designed and constructed inof the same size and structure, are were highly insulated with triple Low-E coating windows; the insulation level of the walls is was $0.13W/m^2K$ and that of the roof is was $0.10W/m^2K$. As electric houses, all of the energy supplied to the houses, including for cooking, is was supplied by electricity. A and 3~4 kWp of photovoltaic system and a 3~5 kW of ground source heat pump (GSHP) were installed in each house tofor providing provide space heating/and cooling and hot water are installed. We constructed a Web-based remote monitoring system in order to understand energy consumption and the dynamic behavior of the energy system. T, and the results of our metering data analysis of 2013 are as follows. First, the annual residential energy consumption is was 4,400 kWh (${\sigma}=1,209$) and GSHP energy consumption is was 5,182 kWh (${\sigma}=1,164$). Second, residential energy consumption ranked highest in average energy usage, with at 45% of the total, followed by heating with at 30%, hot water supply with at 17% and cooling with at 6%. Third, the average energy independence rate is was 51.8%, the GFA (Gross gross floor area) criteria average energy consumption unit is was $48.7kWh/m^2yr$ (${\sigma}=10.1$), and the net energy consumption unit (except the energy yield of the PV systems) is was $24.7kWh/m^2yr$ (${\sigma}=8.8$).

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.9
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• pp.20-27
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• 2014

The power consumption pattern of high-speed railway has rarely during night time. But, during service time, the power is consumed irregularly related to train operation. Especially certain unusual about 1-2 days of service time interval to indicate the power consumption is rapidly growing phenomenon, which causes the capacity of the power contract is the annual electricity bill to rise rapidly as the cause. Normally, amount of peak power consumption bill rate at railway substation is over 20% of total electrical bill. Therefore, high-speed railway substation is expected to be considerably larger savings by reducing the peak power of the default charge(demand power).

• International Journal of Advanced Culture Technology
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• v.4 no.1
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• pp.1-9
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• 2016

The demand for energy in Thailand has been continually increasing as the economic and social country grows. Approximately 60% of Thailand's primary energy is imported, mostly petroleum products. In 2008 Thailand's total energy consumption was 80,971 ktoe and the net price of energy imported was up to 1,161 billion Baht which is equivalent to 12.8% of GDP at the current price. The energy consumption or energy demand has been growing at an annual compounded growth rate of 6.42% and the peak electric power demand and electricity consumption was recorded at 22,568 MW and 148,264 GWh and grew at a rate of 7.0% and 7.5% per annum during the period from 1989 to 2008. The gross agriculture production in 2008 was recorded at 135.4 Mt which represents agriculture residue for energy at 65.73 Mt, which is equivalent to energy potential of about 561.64 PJ or 13,292 ktoe an increase in average of 5.59% and 5.44% per year respectively. The agricultural residues can converted to 15,600 GWh/year or 1,780 MW of power capacity. So, if government sector plan to install small biomass gasification for electricity generation 200 kW for Community. The residue agricultural is available for 8,900 plants nationwide. The small biomass power generation for electricity generation not only to reduce the energy imports, it also makes the job and income for people in rural areas as well. This paper's aim is to report the energy situation in Thailand and has studied 5 main agricultural products with high residue energy potential namely sugarcane, paddy, oil palm, cassava, and maize appropriate for small electricity production. These agricultural products can be found planted in many rural areas throughout Thailand. Finally, discuss the situation, methods and policies which the government uses to promote small private power producers supplying electricity into the grid.

• Journal of the Korean Society for Advanced Composite Structures
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• v.4 no.2
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• pp.15-24
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• 2013

This project is mainly related to evaluation of total energy consumption of low energy house, the exterior envelope of which was wholly composed of structural insulated panels(SIP). The U-value of applied SIP was in the range of 0.189 to $0.269W/m^2{\cdot}K$ and the U-value of pair glass from 0.78 to $1.298W/m^2{\cdot}K$ was applied for window dependent to its function respectively. For comparison of total energy performance, the energy simulation for pilot house was performed to compare with the control house having insulation criteria of Korean building regulation in 2009. Based on simulation of dynamic energy performance, the pilot house saved 48.3% of annual energy consumption while the control house in 2009 consumed as 85.7GJ/y. In case of heating, the result showed that the energy saving ratio amounted to 76.7%. For $CO_2$ emission, the pilot house diminished approximately 35.4% from $6,208.4kgCO_2$ to $4,009.2kgCO_2$. In payback period to early investment, it was analyzed the pilot house took 7.8 years, when the low energy house built by other insulation method with same thermal perfusion took 11.5 years. From this result, it is considered that the SIP is more effective, economic to Green Home application.

• Journal of Hydrogen and New Energy
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• v.33 no.3
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• pp.247-254
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• 2022

Slush hydrogen containing liquid and solid hydrogen is expected to achieve zero boil-off by suppressing boil-off gas because heat of fusion for solid absorbe the heat ingress from atmosphere. In this paper, quantitative analysis on storage cost considering specific energy consumption between 1,000 m³ class liquid hydrogen storage system with re-liquefaction and slush hydrogen storage system during equivalent zero boil off period. Even though approximately 50% of total storage capacity should be converted into solid phase during the initial cargo bunkering, total energy consumption to convert into slush hydrogen is relatively 25% less than re-liquefaction energy for boil off hydrogen during zero boil off period. That's because energy consumption of slush phase change take up only 1.8% of liquefaction energy. moreover, annual revenue requirement including CAPEX, OPEX and electric cost for slush hydrogen storage could be more reduced approximately 32.5% than those of liquid hydrogen storage and specific energy storage cost ($/kg-H₂) could also be lowered by about 41.7% compared with liquid hydrogen storage.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.5
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• pp.691-697
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• 2011

In this study, by using the Water footprint technique, the water consumption by washing machines, which holds higher ranks in using water than any other electric appliances, was analyzed during their life cycle. The life cycle is defined as raw materials production step, manufacturing step, and using step. In raw materials production step, Input materials were researched by using LCI DB(Life Cycle Inventory Database) and the water consumption was calculated with consideration of approximately 65% Input materials which were based weight. In manufacturing step, the water consumption was calculated by the amount of energy used in assembly factories and components subcontractors and emission factor of energy. In using step, referring to guidelines on carbon footprint labeling, the life cycle is applied as 5 years for a washing machine and 218 cycles for annual bounds of usage. The water and power consumption for operating was calculated by referring to posted materials on the manufacture's websites. The water consumption by nation unit was calculated with the result of water consumption by a unit of washing machine. As a result, it shows that water consumption per life cycle s 110,105 kg/unit. The water consumption of each step is 90,495 kg/unit for using, 18,603 kg for raw materials production and 1,006 kg/unit for manufacturing, which apparently shows that the using step consume the most water resource. The water consumption by nation unit is 371,269,584tons in total based on 2006, 83,385,649 tons in both steps of raw material production and manufacturing, and 287,883,935 tons in using step.

• Horticultural Science & Technology
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• v.31 no.1
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• pp.103-109
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• 2013

Estimating the high tuber solids needs a simulation system on potato growth, and its development should be obtained by using agricultural elements which analyze the relationship between crop growth and agricultural factors. An accurate simulation to predict solids level against climatic change employs a calculation of in vivo energy consumption and bias for growth and induction shape in a slight environmental adaptation. So, to calculate in vivo energy consumption, this study took a concept of estimate of the amount of basal metabolism in each tuber. In the validation experiments, the results of measuring solid accumulation of potatoes harvested at dates suggested by simulation agreed with the actual measured values in each regional field during the growth period of years from 2006 till 2010. The mean values of tuber solids level and inter-annual level variation in validation experiments were predicted well by the simulation model. And also, the results of validation experiments represent that concentration of tuber solids were due mainly to the duration of sunshine, above 190 hours per a month, and the cumulative amount of radiation, above 2,200 $MJ{\cdot}m^{-2}$, of the effective growth period.

• Journal of the Korea Institute of Building Construction
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• v.10 no.2
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• pp.97-104
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• 2010

This study evaluated the energy efficiency of a windows system using built-in blinds, with regard to their insulation performance and their blocking of solar radiation. The study took advantage of the "Physibel Voltra" program as a physical simulation of heat transfer. To simulate the "Physibel Voltra" program, I practiced a mock-up test to determine heating quality and translation condition. I analyzed the propensity to annual energy consumption, the annual quantity of heat transfer, and the annual cooling and heating cost through a computer simulation for one general household in an apartment building. In the test, it was found that compared to a general windows system, a windows system with built-in blinds reduced the annual heat transfer by 10% in cooling states and by 11% in heating states when the blind was up. When the blind was down, the windows system with built-in blinds reduced the annual heat transfer by 25% in cooling states and 30% in heating states. When a windows system with built-in blinds is compared with a general windows system, the quantity of cooling and heating loads is reduced by 283.3kw in cooling states and 76.3kw in heating states. This leads to a reduction in the required cooling and heating energy of 359.6kw per house. It is thus judged that the use of a windows system with built-in blinds is advantageous in terms of reducing greenhouse gas emissions, because the annual TOE (tons of oil equivalent) per house is reduced by 0.078TOE, while $tCO_2$ is reduced by $0.16tCO_2$. In addition, compared with a general windows system, the cost of cooling and heating loads in the system reduces the annual cooling cost by 100,000won, and the annual heating cost by 50,000won. Ultimately, this means that cooling and heating loads are cut by 150,000won per year.