• Solar Energy
• /
• v.11 no.2
• /
• pp.70-76
• /
• 1991

Electrochemical reaction utilizing the semiconducting photoanodes can be applied to the photoelectrolysis of water to produce hydrogen. In this preliminary experiment, $TiO_2$ photoanodes were prepared by sintering anatase-$TiO_2$ powder at $1,250^{\circ}C$ and thermal oxidizing titanium plate at $850^{\circ}C$ in air and oxygen, respectively. Their surface structures were observed by XRD and optical microscope. I-E characteristics of thermally oxidized $TiO_2$ photoanode were also investigated under illuminated and dark conditions using 1 N and 0.1 N NaOH electrolyte solutions.

• New & Renewable Energy
• /
• v.17 no.1
• /
• pp.50-60
• /
• 2021

This study investigated the reference case in the UK where legality and sustainability were systematically established for forest biomass represented by wood pellets. The UK is the country that best utilizes the trade value of wood pellets based on sustainability, with bioenergy accounting for 31% of total renewable energy production. The UK imported wood pellet, estimated 8,697 thousand tons in 2019. The UK government has continuously improved the renewable generation policy system to ensure the sustainability of wood pellets. The weighted average greenhouse gas emissions of a UK biomass power plant that received a Renewable Obligation Certificate (ROC) in 2018-19 was 26.71 gCO2e/MJ. These power plants are expected to meet the upper limit of 72.2 gCO2e/MJ by 2025. To issue an ROC, the biomass power plant must demonstrate that 70% of its total biofuel usage is sustainable. The UK uses the Sustainable Biomass Program (SBP) certification system, which is gradually expanding to other European countries, to prove the sustainability of biomass energy fuels. Global wood pellet production with SBP certification in 2019 was 10.5 Mt. This trend has significant implications for introducing additional sustainability into the wood pellet policy of South Korea.

• The Journal of Information Systems
• /
• v.28 no.1
• /
• pp.115-132
• /
• 2019

Purpose The purpose of this study is to explain the agrophotovolatic system built by the Korea South-East Power Company and to propose methods to activate the agrophotovolatic system for the development of the renewable energy industry. Design/methodology/approach We conducted a three-step simulation in order to design a photovoltaic module, and we built the agrophotovolatic system based on the results of the simulation. Then, we analyzed the monthly generation of power and the rice harvests produced on farmland using the photovoltaic module. Based on the results of the analysis, we proposed institutional improvements to increase the use of the agrophotovolatic system, and we proposed new business models to increase the participation of farmers and business persons. Findings When we compared the agrophotovolastic system with the general photovoltaic system, we found that the agrophotovoltaic system had higher utilization rates and power generation. An analysis of rice produced on farmland using the photovoltaic module showed that more than 80% of the rice produced on general farmland was harvested. We suggested activation plans that involved the revision of the farmland law and the introduction of renewable energy certificate (REC). We also proposed a land lease model and a farmer participation model as two new business models, and we conducted economic evaluations and sensitivity analyses for both models.

• Journal of international Conference on Electrical Machines and Systems
• /
• v.2 no.3
• /
• pp.361-366
• /
• 2013

This paper presents the effect on application of the flywheel energy storage system (FESS) for load frequency control (LFC) of an interconnected 2 area power system. To do this, the control characteristics with the FESS were compared with that of the conventional governor controller. The controller for the FESS control and the governor control used a PID type controller. Both the FESS PID controller and the governor PID controller using genetic algorithm (GA) were designed to optimize the PID parameters. The frequency and generation output characteristics with the only FESS controller and with the only conventional governor controller were compared. To verify robust performance of the FESS controller, the computer simulations were performed under various disturbances. The simulation results showed that the FESS controller provided better dynamic responses in comparison with the conventional governor controller.

• New & Renewable Energy
• /
• v.1 no.4 s.4
• /
• pp.55-59
• /
• 2005

In this paper, a new drive system(SHS) for hybrid electric vehicle is proposed. As dual rotor hybrid electric vehicle using planetary gearsets, the SHS has the advantages of both series and parallel systems. The output speed and torque of SHS can be determined at specific point regardless of the engine's operating point. When the size of generator which is used in SHS is same as in THS, the SHS has more activities of engine control due to the ability that is operated in lower speed range. To maximize the performance of system, we carried out optimization for the three parameters that are engine, motorl and motor2. As the result of the optimization, we confirmed the SHS is more preferable to THS in fuel consumption and acceleration area.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.10 no.11
• /
• pp.1271-1276
• /
• 2015

The recent trend is that diesel power generation on islands where its prime cost for power generation is high is replaced by new and renewable energy. Therefore, south Jeolla province is progressing the construction project of self-sufficient islands for the areas where power is supplied by depending on diesel generators, which is the project that power is supplied through eco-friendly energy source using sunlight, wind power and energy storage device etc. However, it is difficult to construct new and renewable energy source with the capacity to respond to the load perfectly due to its environmental and geographical conditions regarding capacity design of new and renewable energy. Besides, Microgrid design considering appropriate capacity design of the system components and efficient operation is required through the analysis of climate conditions and load patterns from the design stage for optimal composition of a hybrid system with economic feasibility. Therefore, this study is aimed to conduct a research on optimal combination, capacity calculation and economic feasibility by comprising a hybrid power generation system which will replace 40% of power generation by diesel as new and renewable energy source for Geomun Island where has more than 300 households and requires expansion of the facility among islands located in southwest coast.

• Journal of the Korean Solar Energy Society
• /
• v.32 no.6
• /
• pp.68-75
• /
• 2012

Small hydropower is one of the many types of new and renewable energy, which is planning to develop, as the country is abundant in endowed resources. In order to fully utilize small hydropower resources, there is a need for greater precision in quantifying small hydropower resources and establish an environment in which energy sources can be discovered using the small hydropower resource management system. This study has given greater precision to calculate annual electricity generation and capacity of small hydropower plants of Nakdong river system by inquiring into average annual rainfall, basin area and runoff coefficient, which is anticipated to promote small hydropower resources utilization. Small hydropower resource management system was also established by additionally providing base information on quantified small hydropower resources and analysis function and small hydropower generator status, rivers, basin, rainfall gauging station, water level gauging station etc.. Small hydropower resource management system can be used gather basic information for positive applications of small hydropower energy nationwide.

• 한국태양에너지학회:학술대회논문집
• /
• 2011.04a
• /
• pp.241-245
• /
• 2011

Small hydropower is one of the many types of new and renewable energy, which South Korea is planning to develop, as the country is abundant in endowed resources. In order to fully utilize small hydropower resources, there is a need for greater precision in quantifying small hydropower resources and establish an environment in which energy sources can be discovered using the small hydropower resource management system. This study has given greater precision to calculating annual electricity generation and installed capacity of small hydropower plants of Han river system by inquiring into average annual rainfall, basin area and runoff coefficient, which is anticipated to promote small hydropower resources utilization. Small hydropower resource management system was also established by additionally providing base information on quantified small hydropower resources and analysis function and small hydropower generator status, rivers, basin, rainfall gauging station, water level gauging station etc.. Small hydropower resource management system can be used gather basic information for positive applications of small hydropower energy nationwide.

• 한국태양에너지학회:학술대회논문집
• /
• 2011.11a
• /
• pp.354-358
• /
• 2011

Small hydropower is one of the many types of new and renewable energy, which South Korea is planning to develop, as the country is abundant in endowed resources. In order to fully utilize small hydropower resources, there is a need for greater precision in quantifying small hydropower resources and establish an environment in which energy sources can be discovered using the small hydropower resource management system. This study has given greater precision to calculating annual electricity generation and installed capacity of small hydropower plants of Nakdong river system by inquiring into average annual rainfall, basin area and runoff coefficient, which is anticipated to promote small hydropower resources utilization. Small hydropower resource management system was also established by additionally providing base information on quantified small hydropower resources and analysis function and small hydropower generator status, rivers, basin, rainfall gauging station, water level gauging station etc.. Small hydropower resource management system can be used gather basic information for positive applications of small hydropower energy nationwide.

• Journal of Engineering Education Research
• /
• v.27 no.3
• /
• pp.26-33
• /
• 2024

This study aimed to verify the learning effectiveness of students who took courses in the field of new and renewable energy, which have been operated within a convergence university system. To achieve this, data were collected from 1,228 students who participated in 34 courses jointly developed and conducted by seven universities as part of standard curriculum offerings. The study analyzed learning effectiveness (course satisfaction, transfer motivation, learning transfer, creativity-convergence competency) using Excel 2018 and SPSS 25.0. It also examined inter-university differences in learning effectiveness and identified factors influencing creativity-convergence competency. The main findings are as follows: (a) Course satisfaction (M= 4.20), transfer motivation (M=3.62), learning transfer (M= 4.06), and creativity-convergence competency (M=3.92) were generally high. (b) Analysis of learning effectiveness differences between universities showed no significant differences among universities A, B, C, D, and E. University F was lower compared to other universities, while University G was significantly higher than others. (c) Sex, grade, number of courses taken, course satisfaction, transfer motivation, and learning transfer had effect on creativity-convergence competency. The results of this study provided implications for promoting activities to attract students, expanding transfer opportunities, and ensuring student agency.