최근 대기오염으로 인한 환경오염을 줄이고자 국제 산업계의 노력의 일환으로 국제해사기구(IMO)의 규제 발효등으로 이어지 고 있다. IMO는 EEXI,EEDI,CII 등 선박에서 나오는 대기오염을 줄이기 위해 각종 규제를 발효시키고 선박에서 소모되는 전력을 줄여 에너 지를 절약하는 방안을 추진하고 있다. 선박에서 사용되는 전력의 대부분은 전동기가 차지한다. 선박에 설치된 전동기 중 큰 부하를 차지 하는 기관실 송풍기는 수요와 관계없이 정속운전으로 운전하기 때문에 주파수제어를 통한 에너지절감을 기대할 수 있다. 본 연구에서는 발전기의 과급기에 연소공기를 공급하는 발전기 송풍기의 전동기 주파수를 제어하여 에너지 절감에 대한 실효성을 입증하였다. 송풍기 주파수 입력에 따른 과급기출구 온도의 출력 데이터를 기반으로 시스템을 모델링하고, 과급기 출구온도를 목표값으로 하여 주파수를 제 어하는 PI 제어계를 형성하여 과급기 설계기준 출구온도를 유지하면서 송풍기의 주파수 제어를 통해 연간 15,552kW 전력소모량을 절감하 였다. 송풍기 팬 주파수 제어를 통한 에너지절감액의 유효성은 하계(4월~9월) 및 동계(3월~10월) 기간동안 검증하였으며 이를 토대로 실습 선의 연간 6,091천원의 유류비 절약과 이산화탄소 8.5Ton, SOx 2.4kg, NOx 7.8kg의 대기오염물질 저감을 달성하였다.
Test of the operating characteristics and energy saving performance of a container cooling system that reduces the operating energy of a refrigeration system using a loop thermosyphon heat exchanger that removes heat by temperature difference between outdoor and indoor was performed. As a result of the experiments, when the loop thermosyphon and the refrigeration system were operated simultaneously, the refrigeration system operated intermittently by reducing the heat load. As the temperature difference between indoor and outdoor increased, the operating time of the refrigeration system decreased and the energy efficiency rate increased. Energy efficiency rate showed a tendency to increase with increasing temperature difference, and the predicted correlation of energy efficiency rate using the performance of the loop thermosyphon heat exchanger and the refrigeration system was relatively consistent with the experimental value.
We present a facile, room temperature synthesis of poly(ethylenealt- maleic anhydride)-graft-poly(propylene glycol) (PEMA-g-PPG) graft copolymer-based CO2/N2 gas separation membrane with 100% conversion reaction without any further purification process. As confirmed by the Fourier transform infrared (FT-IR) and nuclear magnetic resonance (1H NMR) spectroscopy, the PEMA-g-PPG was successfully synthesized with 100% conversion of PEMA and PPG monomers. It was confirmed that the PEMA-g-PPG was amorphous and rubbery state according to the X-ray diffraction (XRD) and differential scanning calorimetry (DSC0 results. Therefore, PEMA-g-PPG/polysufulfone composite membrane exhibited high performance of CO2 permeability (99.1 Barrer) and selectivity (82.6 for CO2/N2 and 26.8 for CO2/CH4), surpassing conventional PEBAX block copolymer membrane.
Heating and air conditioning system is changing rapidly from the traditional HVAC central supply system to the individual supply system with electrical heat pump system (EHP) in Korean school buildings. The individual supply system has advantages to turn on and off individually and to adjust the thermal comfort separately, but energy is wasted in the unoccupied classroom when the last leaving occupant does not turn off the controller. If the controller is to be off automatically while the classroom is not in use, energy consumption would decrease dramatically. This project aims to cease the unnecessary EHP supply in vacant classroom by inputting the class schedule from the central control room to reduce the energy-spending. Experimental measurements were carried out between the controlled classroom that is turned off when not in use and the uncontrolled room that is turned on continually. Occupant's comfort and energy consumption were measured and compared between the controlled case and the uncontrolled case. The energy consumption of controlled classroom case is 30-60% less than that of the uncontrolled classroom case. This result shows that controlling the cooling supply for the unoccupied classroom using the class schedule can decrease the energy consumption remarkably. This supply control system can be used to conserve energy in school structures like universities.
Supply chain including transportation expend the 21% of domestic energy consumption. It is necessary to diminish the excess energy usage at entire supply chain. This paper deals with the application of MFCA(Material Flow Cost Accounting) for SCM to save energy consumption. We construct the material center corresponding to each logistics function in order to apply the MFCA for GCM(Green Chain Management). We also construct the MFCA framework which consists of MFCA Database Management, MFCA Visualization, GCM Data Integration, GCM Data Tracking, and MFCA Data Predict & Assignment. We expect to help determining the range of logistics function to apply the MFCA for GCM.
The hybrid cooling system of vapor compression system and naturally circulating coolin system using R-410a for indoor mobil tele-communication center(IMTC) is developed and its performance is experimentally studied. Its results are summarized as follows. First, cooling capacity of naturally circulating cooling system is proportional to indoor and outdoor temperature difference and it has max. 4,550 kcal/h at indoor and outdoor air temperature difference 15℃. Second, heat exchangers of evaporator and condenser should be designed and constructed to be able to get maximum refrigerant capacity by naturally circulating force and to enhance heat transfer by refrigerant. Third, cooling capacity of hybrid cooling system has optimum operating point according to refrigerant charging capacity and refrigerant charging capacity of naturally circulating cooling system is 30~50% more than vapor compression refrigeration system.
Since korea must get 5.2% reduction of green gas emission and insecurity of economic impact is on the increase due to unstable oil market, the demands of energy saving techniques are increasing. In this paper, we investigate necessity of development of enormous energy used cleanroom energy saving techniques furthermore we also investigate the adoption of dependability management system to develop the energy saving cleanroom development process.
This study is provide information in the development of energy conservation technologies by means of technological demand survey covering energy market and industrial field among energy-related technologies. For this purpose, we check both the present
This study is to provide information in the development of energy conservation technologies by means of technological demand survey covering energy market and industrial field among energy-related technologies. For this purpose, we check both the present state of energy technologies and trends of social change in Korea, and then combine social needs with major, bottleneck, and essential technologies required for the future. The range of this study covers the field of industry, kiln, furnace, metal, building, transport, and electricity. For case study, valid 120 companies among the 500 companies selected randomly in the energy data-base of Korea institute of energy research (KIER) are considered.
A temperature control system was developed to save energy in freeze dryer. The objective part in the freeze dryer was a shelf with an electrical heater and cooling compressor. The shelf was a fluid circulation heat exchanger. The temperature control of the shelf is generally a feedback control by present and set values of the shelf temperature only, whereas in new control algorithm the circulating fluid temperature and fluid circulating speed were included as well. The control algorithm was based on a concept of refraining the heater and cooler from being in operation if unnecessary. Actuators in use were mainly thyristor for heater, relay for cooling compressor, inverter for fluid circulating pump, etc. Type of Interfaces were RS232C, and digital-analog converter and digital-output converter. Program language was Visual Basic 6.0. Finally, control performance by the new algorithm could be improved in terms of energy saving and accuracy.
Diffusions of energy conservation technology are very important class in our country that resources and energy are lacking, and development, transfer, diffusions etc.. of energy conservation technology can speak as one method that can improve country competitive power along with company competitive power. But, in the case of our country, present condition grasping about energy conservation technology passing․induction did not consist. This research grasp present condition about energy conservation technology passing․induction of our country and present direction for energy conservation technology activation, for which connected company into question investigation enforce and behaved frequency analysis and crossing analysis etc.
Purpose – Electrical energy saving is one of the practical virtues relating to sustainable living. Therefore, policy-makers has tried to find a way to change the behaviors of individuals to encourage them to actively practice electrical energy saving, even if they have never had this concern or have only passively practiced electrical energy saving to this point. Prior research related to electrical energy saving can be categorized into several types. The first is focused on consumer characteristics linked to electrical energy saving. These studies are based on individual or household socio-demographic variables (e.g., age, gender, household income, education level, occupants, marital status, number of households), and psycho-graphics (e.g., environmental consciousness, value, attitude, motivation, lifestyle). The second is focused on policies (e.g., monetary incentives, information sharing, social comparison, feedback), and technologies (e.g., energy-efficiency home appliances, energy-reduced products, renewable resources). People generally have a favorable attitude towards electrical energy saving, while electrical energy saving practices tend to be less favorable. Therefore, it is necessary for policy-makers to seek out gaps between attitudes and behaviors and find alternatives to reduce these gaps. This study investigates the influence of authenticity on the behavioral intention of electrical energy saving. It is supposed that electrical energy saving practices are likely to be stronger as authenticity of individual or household becomes stronger. This study reviews prior literature and examines various studies to provide an understanding of the relationships between authenticity and electrical energy saving behavioral intention.
Research design, data, and methodology – Hypothesis was drawn from analysis based on previous research. The items related to authenticity and electrical energy saving were selected from items found in previous research. To verify this hypothesis, data were collected via experimental survey method and the resulting data were analyzed using reliability analysis, correlation analysis, and hierarchical regression analysis.
Results – This study found that authenticity had a positive impact on the behavioral intention of electrical energy saving. The higher the perceived degree of authenticity, the higher the behavioral intention of electrical energy saving.
Conclusions – This study assesses the impact of authenticity on the behavioral intention of electrical energy saving. In order to enhance the practice of electrical energy saving, it is efficient strategy for policy-maker to improve the perceived authenticity of individuals.
The transportation productivity is the throughput of utility per locations of resources and is able to be brought forth by using transportation mode. Therefore, Oil energy is necessary for using the transportation mode that is mainly consisted of four parts trucks, railroad, ship and aircraft, and Oil quantity used for such modes is not respectively same. Noticing Such a Point, the purpsoe of this paper is to reaserch the transportation mode of convertable cargoes and to minimize energy consumption quantity by adopting such a mode. We must ttend to Energy-Intensity, Transportation, Distance and cargo quantity for selecting the transport mode to energy consumption and the minimization of transportation energy consumption is concluded in the next LP Problem. As above mentioned, we can find the solution of Xij by the LP when Xij is transportation cargo per routes, and fullfil the minimization of Energy Consumption.