• Electrical & Electronic Materials
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• v.31 no.1
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• pp.14-23
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• 2018

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.583-592
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• 2016

IMO (International Maritime Organization) in the UN (United Nations) set up that aim at reducing $CO_2$ emission from ship by up to 30 percent until 2030. The final purpose of this study is the development of marine thermoelectric generation system using waste heat from vessel of internal combustion engines. Before the development of marine thermoelectric generation system, this paper carried out the fundamental heat analysis of marine thermoelectric generation system. It was able to obtain the valuable results about the efficiency improvement of the thermoelectric generation system. The results is as follows : 1) It was confirmed that the efficiency of thermoelectric generation system improves to 8.917 % with increasing the temperature difference of peltier module by reducing the temperature difference between peltier module and heat source at the hot side. 2) System efficiency according to change in the external load resistance was confirmed that the change width of about 6 % which does not significantly occur. 3) System efficiency in the case stainless steel at the same condition is 8.707 %. System efficiency could be confirmed that the stainless steel is higher than duralumin (8.605 %), copper (8.607 %).

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.1
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• pp.1-12
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• 2010

An analysis model considered the manufacturing factors and the pellet size has been developed in order to predict the performance characteristics of thermoelectric modules as generators. Since the electrical internal resistance has a significant role in the performance of thermoelectric modules, the variations of electrical internal resistance with operating temperature are experimentally measured. The modified electrical internal resistance calculated from an experimental correlation is applied to the analysis model. To verify the modified analysis model, the output voltage, output current and output power are compared with experimental results for the operating temperature conditions of $T_h=85^{\circ}C$ and ${\Delta}T=40^{\circ}C$. The modified analysis shows a good agreement with the experimental results in terms of the output voltage, current, and power.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.5
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• pp.259-267
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• 2010

An experiment has been performed in order to investigate the characteristics of multiple thermoelectric modules (TEMs) with electrical circuits. The open circuit voltage of TEM connected parallel circuit is equal to the sum of individual TEMs. In contrast, the open circuit voltage is equal to the average of that individual TEM for a series circuit. The power output and conversion efficiency of TEM for both parallel and series circuits increase as the operating temperature conditions for individual TEMs becomes identical. Comparing parallel with series circuits, the power generation performance is more excellent for series circuit than parallel circuit. This result is attributed to the power loss from the TEM with better power generation performance.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.50-50
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• 2010

Seebeck 효과를 이용한 열발전 소자는 에너지 절약에 대한 사회적인 필요성이 크게 대두됨에 따라 산업폐열 등 저급의 열에너지를 이용한 발전과 무인 작동이 가능하다는 점에서 군사 의료용 및 인공위성의 보조전원의 특수 목적용 전원등으로 사용하고 있다. 또한 Peltier 효과를 이용한 열전냉각 소자는 전자 광학기의 냉각 및 항온유지 등에 이용되고 있다. 이러한 열전소자 중 Bismuth Telluride계 열전소자는 상온부근에서 작동효율이 우수한 것으로, 단결정 또는 소결재를 이용하고 있다. 박막형 열전재료 및 이를 이용한 열전박막소자의 제조와 특성에 관한 연구가 활발히 진행되고 있다. 본 연구에서는 Bi-Te계 열전박막을 기상 증착법으로 제조하였고, 이에 사용되는 다양한 전구체 ($Bi(Me)_3$, $Bi(Et)_3$, $Te(iPr)_2$, $Te(Et)_2$, $Te(t-Bu)_2$)에 대한 증기압, 순도 측정 및 기상 분해특성 평가를 진행하였다. 전구체의 증기압 및 순도 측정을 위해선 자체적으로 제작한 시스템을 활용하였고, 기상 분해특성 평가를 위해선 특별히 제작된 플라즈마 열처리 모듈을 활용하였다. 이러한 연구는 열전박막소자의 제조를 위한 전구체의 선별조건을 제시하는데 기여할 수 있을 것으로 생각된다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.3
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• pp.277-284
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• 2012

In this study, a heat-transfer performance analysis is carried out for a multi-channel volumetric air receiver for a solar power tower. On the basis of a series of reviews regarding the relevant literature, a calculation process is proposed for the prediction of the wall- and air- temperature distributions of a single channel at given geometric and input conditions. Furthermore, a unique mathematical model of the receiver effectiveness is presented through analysis of the temperature profile. The receiver is made of silicon carbide. A total of 225 square straight channels per module are molded to induce the air flow, and each channel has the dimensions of $2mm(W){\times}2mm(H){\times}0.2mm(t){\times}320mm(L)$. The heat-transfer rate, temperature distribution and effectiveness are presented according to the variation of the channel and module number under uniform irradiation and mass flow rate. The available air outlet temperature applied to the solar power tower should be over $700^{\circ}C$. This numerical model was actually used in the design of a 200 kW-level commercial solar air receiver, and the required number of modules satisfying the thermal performance could be obtained for the specified geometric and input conditions.

• Applied Chemistry for Engineering
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• v.27 no.4
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• pp.353-357
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• 2016

Following the population growth and civilization, resulted in energy-mass consumption society, research efforts on enhancing efficiency of traditional energy sources has been investigated. Among many alternatives, thermoelectric power generation technologies are highlighted as one of solutions for high heat energy efficiencies. Currently, the research area of thermoelectric power generation has been achieved over two of ZT value, which seems to have enough competitiveness as following the development of nano-technologies, in particular, for waste heat recovery, and the development of thermoelectric materials is still ongoing to obtain higher energy efficiencies. In this review, the recent development of thermoelectric materials and module technologies categorized by different temperature regions was briefly introduced.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.777-784
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• 2017

Energy harvesting through a thermoelectric module normally makes use of the temperature gradient in the system's operational environment. Therefore, it is difficult to obtain the desired output power when the system is subjected to an environment in which a low temperature gradient is generated across the module, because the power generation efficiency of the thermoelectric device is not optimized. The utilization of solar energy, which is a form of renewable energy abundant in nature, has mostly been limited to photovoltaic solar cells and solar thermal energy generation. However, photovoltaic power generation is capable of utilizing only a narrow wavelength band from the sunlight and, thus, the power generation efficiency might be lowered by light scattering. In the case of solar thermal energy generation, the system usually requires large-scale facilities. In this study, a simple and small size thermoelectric power generation system with a solar concentrator was designed to create a large temperature gradient for enhanced performance. A solar tracking system was used to concentrate the solar thermal energy during the experiments and a liquid circulating chiller was installed to maintain a large temperature gradient in order to avoid heat transfer to the bottom of the thermoelectric module. Then, the setup was tested through a series of experiments and the performance of the system was analyzed for the purpose of evaluating its feasibility and validity.

• Journal of the Korean Solar Energy Society
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• v.39 no.1
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• pp.21-32
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• 2019

Solar hot water system produces hot water using solar energy. If it is not used effectively, overheating occurs during the summer. Therefore, a lot of research is being done to solve this. This study develops thermoelectric power module applicable to solar hot water system. A thermoelectric material can directly convert thermal energy into electrical energy without additional power generation devices. If there is a temperature difference between high and low temperature, it generate power by Seebeck effect. The thermoelectric module generates electricity using temperature differences through the heat exchange of hot and cold water. The water used for cooling is heated and stored as hot water as it passes through the module. It can prevent overheating of Solar hot water system while producing power. The thermoelectric module consists of one absorption and two radiation part. There path is designed in the form of a water jacket. As a result, a temperature of the absorption part was $134.2^{\circ}C$ and the radiation part was $48.6^{\circ}C$. The temperature difference between the absorption and radiation was $85.6^{\circ}C$. Also, The Thermoelectric module produced about 122 W of irradiation at $708W/m^2$. At this time, power generation efficiency was 2.62% and hot water conversion efficiency was 62.46%.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.1942-1947
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• 2007

A thermoelectric module can be used for cooling or power generation. The basic requirements to achieve a significant thermoelectric performance are the same for both generators and coolers. Thermoelectric modules with $Bi_2Te_3$ materials are usually employed in the cooling applications below room temperature but it can also be used for the power generation in the similar temperature range. In the present study, the power generation with a $Bi_2Te_3$ thermoelectric module has been investigated. The temperature difference between the hot and cold sides of the module is maintained with electric heater and cold water from the circulating water bath. The result shows that the electric current generated increases with temperature difference and decreases with the load resistance. However, the voltage increases with both the temperature difference and load resistance. The electric power increases with temperature difference and it has the maximum value when the load resistance is about 4 ${\Omega}$ for a given device.