• 한국신재생에너지학회:학술대회논문집
• /
• 2010.06a
• /
• pp.170.2-170.2
• /
• 2010

The amount of the heating and cooling energy of water source heat pump using the raw water from the Paldang water intake station is investigated in the study. The Han river water is conveyed in the large-size shallowly buried pipe. Averaged water temperature at the position, 27 km from the Paldang water intake station, is increased by $1.11^{\circ}C$ due to the geothermal energy transfer under the ground, therefore the raw water has more thermal energy than the river water. To estimate of the thermal energy for the raw water, it is assumed that the water source heat pump is used for the heating and cooling ventilation. When $5.0^{\circ}C$ temperature difference energy of the raw water is used in the heat pump system all the year except for the January and February in which $3.0^{\circ}C$ temperature difference energy is used. It is predicted that total 5,766.3 Tcal could be used in the metropolitan area a year, which is about 3.0% of the river water unutilized energy resources.

• Convergence Security Journal
• /
• v.18 no.2
• /
• pp.3-10
• /
• 2018

The existing smart grid, which is centered on the power grid, is rapidly spreading to new energy and renewable energy such as heat and gas, which are expressed as smart energy. Smart Energy interacts with electric energy and is connected to wired / wireless network based on IoT sensor based on energy analysis using AI to rapidly expand ecosystem with various energy carriers and customers. However, smart energy based on IoT is lacking in technological and institutional preparation for security compared to efforts to activate the market according to the interests of government and business operators. In this study, we will present Smart Energy 's privacy policy in terms of value system(CPND) of convergence ICT.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.12 no.1
• /
• pp.23-28
• /
• 2009

There is several ways of recycling methods for waste FRP boats. The main one is mechanical recycling that is one of the simple and technically proven methods. It recently has been reported that FRP can be recycled by separating into laminated glass fiber layers instead of crushing into powder. Even though the mechanical recycling is a good way for the eligibility of laminated glass fiber reinforced material, the system should have another option which can collect resin of FRP. Because the resin is still very useful renewable energy source, that cannot be discarded, But FRP is made up of laminated glass fiber(roving cloth layer) which is fire retardant substances and very hard to break into each layer. Due to the high cost of fossil energy the waste plastics should be regenerated to the source of renewable energy. Laminated glass fiber which is recyclable in a very limited way, is currently a serious barrier to waste FRP boat regenerating. This study is to propose a new extracting method which is efficient and environment friendly FRP waste regenerating system. The recycled glass fiber which is obtained by the separation of the roving layer from FRP waste has been found to be useful for concrete(FRC) products or concrete(FRC) structures as fiber reinforced material. And it can be successively applied to renewable energy applications using the waste resins of FRP residue without laminated glass fiber.

• 한국신재생에너지학회:학술대회논문집
• /
• 2005.06a
• /
• pp.403-407
• /
• 2005

Objective of the research is to demonstrate solar thermal space and ground heating system which is integrated to a greenhouse culture facility for reducing heating cost, increasing the value of product by environment control, and developing advanced culture technology by deploying solar thermal system. Field test for the demonstration was carried out in horticulture complex in Jeju Island. Medium scale solar hot water system was installed in a ground heating culture facility. Reliability and economic aspect of the system which was operated complementary with thermal storage and solar hot water generation were analyzed by investigating collector efficiency, operation performance, and control features. Short term day test on element performance and Long term test of the whole system were carried out. Optimum operating condition and its characteristics were closely investigated by changing the control condition based on the temperature difference which is the most important operating parameter. For establishing more reliable and optimal design data regarding system scale and operation condition, continuous operation and monitoring on the system need to be further carried out. However, it is expected that, in high-insolation areas where large-scale ground storage is adaptable, solar system demonstrated in the research could be economically competitive and promisingly disseminate over various application areas.

• Journal of the Korean Solar Energy Society
• /
• v.36 no.6
• /
• pp.61-69
• /
• 2016

In this study, we analyzed five-year(2011~2015) data for D high school in Seoul area to analyze energy consumption characteristics in high school. The results are summarized as follows. (1) In the result of comparison analysis about 2015 energy consumption by usage, based on primary energy, 18% of energy was consumed in cafeteria, and 82% was consumed in main building. In the case of main building, base and constant load excepting hot water supply in restroom took 40%, heating including freeze protection took 20%, hot water supply in restroom took 14%, and cooling took 8% in order. (2) In the 2015 total energy consumption in D high school based on primary energy, heating energy takes 28%. The range and limit of energy savings coming from the reinforcement of insulation and window performance could be estimated. (3) To introduce new & renewable energy system in high school, electricity-based system is suitable than heat-based system because usage of electric energy is larger than that of heat energy in high school. (4) Five-year energy consumption unit according to heating degree-day showed a linearly increasing trend, and the coefficient of determination(R2) was 0.9763, which means high correlation.

• 한국신재생에너지학회:학술대회논문집
• /
• 2008.05a
• /
• pp.327-330
• /
• 2008

This paper presents monitoring system for 750kW-class DFIG wind turbine generator system and an architecture for applying standardized communication, IEC61400-25. Monitoring and control system is consists of wind turbine PLC, Local and Remote I/O Server, HMI. and Web-server. Proposed System has been demonstrated in Daegi-ri, Kangwon-do, which aims to test local and/or remote monitoring and control system and evaluate the performance of 750kW-class WTS. Finally we described the design of logical nodes and services based on IEC61400-25 and its application scheme.

• 한국신재생에너지학회:학술대회논문집
• /
• 2008.05a
• /
• pp.65-68
• /
• 2008

This paper proposes the parallel operation control algorithm of a power conditioning system (PCS) for a distributed Fuel Cell power generation system. A proposed control algorithm is made good a drawback of the conventional control algorithm. The controller must also supervise the total PCS operation while communicating with the fuel cell system controller. Simulation results are presented to performance of a proposed control algorithm for the PCS.

• 한국신재생에너지학회:학술대회논문집
• /
• 2008.10a
• /
• pp.55-58
• /
• 2008

Residential fuel cell cogeneration systems have gained much interest due to its high efficiency. In this study, we have performed numerical simulation of residential fuel cell cogeneration system which includes a fuel cell/grid hybrid system. The cogeneration system consists of 1kW PEFC, cooling system, inverter/converter and reformer. Several empirical models have been employed for respective components to improve the accuracy of the simulations. The load varies seasonally. The present simulations can successfully predict the characteristics of the hybrid cogeneration system and thus it can be utilized for establishing an optimal operating strategy of the system.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.525-526
• /
• 2007

Recently, there has been growing interest in utilizing distributed generation (DG). However, an insertion of DG to existing distribution system can cause several problems such as voltage variations, harmonics, protective coordination, increasing fault current etc,. The typical protection system of the existing distribution system is designed for radial network. But penetration of DG to distribution system changes existing unidirectional power flow to bidirectional power flow. Therefore, investigation to cover whole field of distribution system must be accomplished such as changing of protection devices rating by increasing fault current, reevaluation of protective coordination. This paper presents that PSCAD/EMTDC simulations was accomplished to analyze effect of DG on the distribution protective coordination. In addition, directional recloser-sectionalizer coordination are evaluates distribution system with DG by using PSCAD/EMTDC simulation.

• 한국태양에너지학회:학술대회논문집
• /
• 2008.04a
• /
• pp.80-85
• /
• 2008

A PVIB(Photovoltaic in Building) system is united by a constituent outer covering and can expect dual effects that reduce expenses for the establishment of a PV system. It is a profitable technology because it does not need a building as it is a stand alone PV system. This paper presents design, operational features analysis, and PCS(Power Conditioning System) of grid-connected 30kW PVIB set up on the library of Dongshin University. For a sustainable photovoltaic system in this area, the data of the PVIB system are collected and analyzed by monitoring system using LabView. PCS of the grid-connected PVIB system, also, is designed for optimal operation with characteristics suggested in this paper.