• Nuclear Engineering and Technology
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• v.53 no.2
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• pp.677-687
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• 2021

The tendency to renewables is one of the consequences of changing attitudes towards energy issues. As a result, solar energy, which is the leader among renewable energies based on availability and potential, plays a crucial role in full filing global needs. Significant problems with the solar thermal power plants (STPP) are the operation time, which is limited by daylight and is approximately half of the power plants with fossil fuels, and the capital cost. Exergy analysis survey of STPP hybrid with PCM storage carried out using Engineering Equation Solver (EES) program with genetic algorithm (GA) for three different scenarios, based on eight decision variables, which led us to decrease final product cost (electricity) in optimized scenario up to 30% compare to base case scenario from 28.99 $/kWh to 20.27 $/kWh for the case study. Also, in the optimal third scenario of this plant, the inner carbon dioxide gas cycle produces 1200 kW power with a thermal efficiency of 59% and also 1000 m3/h water with an exergy efficiency of 23.4% and 79.70 kg/h with an overall exergy efficiency of 34% is produced in the tetrageneration plant.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.349-352
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• 2005

The energy management of an HEV using optimal control and global optimization is thought to be closest to the best operation of the system. However, there are some controversies on the ways of defining the optimization problems and constituting the optimal control simulators. Here, we presented a simulator which adopts the concept of equivalent fuel economy and leads the vehicle to run in a more efficient way. In order to realize the optimal operation of the HEV and check the validity of the control logics, we also developed a forward-facing simulator. The simulator was developed with the Cruise and MATLAB co-simulation interface. Especially, neural network controller was used for the hybrid control module in the simulator. With the simulator, the optimal operation could be converted into hybrid control rules and the validity of the operation was verified.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.243-247
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• 2005

This paper describes an on-going national R&D program for the development of a gas turbine/fuel cell hybrid power generation system and related R&D activities. The final goal of this program is to develop a 200kW-c1ass gas turbine/fuel cell hybrid power generation system and achieve high efficiency over $60\%$ (AC/LHV). In the first phase of the development, a sub-scaled 60kW-class hybrid system based on the 50kW-class microturbine and the 5kW SOFC will be developed for the purpose of concept proof of the hybrid system. Core components such as the microturbine and the SOFC system are being developed and parallel preparation for system integration is being carried out. Before the core components are assembled in the final system. operating characteristics of a hybrid system are investigated from a simulated system where a turbocharger (microturbine simulator) and a modified fuel cell burner test facility (fuel cell simulator) are employed. The 60kW demonstration unit will be built up and operated to provide the valuable information for the preparation of the final full scale 200kW hybrid system.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.5
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• pp.82-91
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• 2014

The combined generator system by integrating several renewable energy sources can share the electrical infrastructure and therefore have the advantage of constructing not only the transmission system but also the power conversion system. Among the various combined renewable system, the wind power and wave power has a high possibility of future growth due to the economic feasibility in offshore environment. This kind of large-scale combined systems might be follow the determination by the transmission system operator's directions and control the output profile by focusing at PCC. However, both renewable energies are depend on the unpredictable environmental variation; it is needed to do the compensation devices. In this paper, the ESS compensation plan is proposed to do output determination of the combined generator system by paying attention to active power of utility grid with the analysis of the controllable elements of the wind and wave power generator. The improvement of the new application technique of the combined system is confirmed through using the PSCAD/EMTDC. The entire simulation process was designed by adopting the active power control according to the reference signal of TSO.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.4_2
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• pp.715-724
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• 2023

Solar energy forecasting is essential for (1) power system planning, management, and operation, requiring accurate predictions. It is crucial for (2) ensuring a continuous and sustainable power supply to customers and (3) optimizing the operation and control of renewable energy systems and the electricity market. Recently, research has been focusing on developing solar energy forecasting models that can provide daily plans for power usage and production and be verified in the electricity market. In these prediction models, various data, including solar energy generation and climate data, are chosen to be utilized in the forecasting process. The most commonly used climate data (such as temperature, relative humidity, precipitation, solar radiation, and wind speed) significantly influence the fluctuations in solar energy generation based on weather conditions. Therefore, this paper proposes a hybrid forecasting model by combining the strengths of the Prophet model and the GRU model, which exhibits excellent predictive performance. The forecasting periods for solar energy generation are tested in short-term (2 days, 7 days) and medium-term (15 days, 30 days) scenarios. The experimental results demonstrate that the proposed approach outperforms the conventional Prophet model by more than twice in terms of Root Mean Square Error (RMSE) and surpasses the modified GRU model by more than 1.5 times, showcasing superior performance.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.78-81
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• 2008

Residential fuel cell cogeneration systems have gained much interest due to its high efficiency. In the present study, we have performed numerical simulation of residential fuel cell cogeneration system which includes a fuel cell/battery hybrid system. The cogeneration system consists of 1kW PEFC, two 60Ah batteries, 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.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.580-583
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• 2006

A small-scale solar concentrating system was developed and demonstrated for supplying process heat required in solar thermo chemical reaction. The concentration system consists of a heliostat equipped with a solar tracking device and a dish concentrator. From the initial thermal test of the concentrating system it was found that the system works very well with around 500-600 concentration ratio capable of supplying about 3kW therml energy to the reactor. Once the concentration system was turned on, the reactor temperature rapidly increased over $1,000^{\circ}C$ and could be maintained high enough for solar chemical reaction.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.1
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• pp.205-212
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• 2023

In the modern society, the extreme weather caused by climate change has brought about exceptional damage in succession over the world due to the use of fossil fuels, and infectious diseases such as COVID-19 worsen the quality of human life. It is urgently necessary to reduce green-house gas and use new renewable energy. The global environmental pollution should be decreased by reducing the use of fossil fuels and using new renewable energy. This paper suggests a system which can function for the environment of four seasons, safety and communication, through the photovoltaic power-based intelligent CCTV, internet and WiFi, and cooling and heating systems, and can optimally manage power, through the real-time monitoring of the production and the consumption of the photovoltaic power. It suggests a hybrid generation system supporting diesel generation without discontinuation in the case of emergency such as system power outage caused by cold waves, typhoons and natural disasters in which the photovoltaic power generating system cannot be used.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.84.1-84.1
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• 2010

Currently, new and renewable energy come into the spotlight, such as solar energy, wind power, fuel cell, hybrid car etc., due to the energy resource is being depleted. Especially, in order to solve like this problem, the study of solar cell manufacturing systems are being extensively researched such as vacuum process. But the major fault of the vacuum process are its expensive production price. On the order hand, Roll-to-roll printing system, the new technology of solar cell manufacturing, has low production price compare with the vacuum process. Also roll-to-roll printing system can decrease the 95% of waste water and 99.9% of harmful gasses than the vacuum process. So we addressed the roll to roll printing system for the flexible solar cell by using printing technology. This roll-to-roll printing system is comprised of various modules, such as web handling module, fine pattern printing module, dry/curing module, uniform coating module and laminating module etc.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.173-178
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• 2005

Recently. we interested in renewable energy due to cost increase of the crude oil, etc. In this study solar assisted hybrid heat pump system that uses the solar heat and air as heat source analyzed by experimentally.'rho system could runs at dual mode. One is thermal storage mode of solar energy at day time and the other is heat pump mode with low temperature air as heat source at night time. In case of setting temperature over the limited range. high temperature water heated at the solar energy collecting tubes supplied to the storage tank. As results. it is founded that the heat pump performance Is higher than general heat pump which using the only air as a heat source. The developed system could be used as main healing equipment for the panel heating for the residential house.