Recently, research on cost reduction and efficiency improvement of crystalline silicon(c-Si) photovoltaic(PV) module has been conducted. In order to reduce costs, the thickness of solar cell wafers is becoming thinner. If the thickness of the wafer is reduced, cracking of wafer may occur in high temperature processes during the c-Si PV module manufacturing process. To solve this problem, a low temperature process has been proposed. Conductive paste(CP) is used for low temperature processing; it contains Sn57.6Bi0.4Ag component and can be electrically combined with solar cells and ribbons at a melting point of 150℃. Use of CP in the PV module manufacturing process can minimize cracks of solar cells. When CP is applied to solar cells, the output varies with the amount of CP, and so the optimum amount of CP must be found. In this paper, in order to find the optimal CP application amount, we manufactured several c-Si PV modules with different CP amounts. The amount control of CP is fixed at air pressure (500 kPa) and nozzle diameter 22G(outer diameter 0.72Ø, inner 0.42Ø) of dispenser; only speed is controlled. The c-Si PV module output is measured to analyze the difference according to the amount of CP and analyzed by optical microscope and Alpha-step. As the result, the optimum amount of CP is 0.452 ~ 0.544 g on solar cells.

In this study, we investigate the relationship between the peeling behavior of the backsheet of a photovoltaic(PV) module and its surface temperature in order facilitate removal of the backsheet from the PV module. At low temperatures, the backsheet does not peel off whereas, at high temperatures, part of the backsheet remains on the surface of the PV module after the peeling process. The backsheet material remaining on the surface of the PV module is confirmed by X-ray diffraction(XRD) analysis to be poly-ethylene(PE). Differential scanning calorimetry(DSC) is also performed to investigate the interfacial characteristics of the layers of the PV module. In particular, DSC provides the melting temperature(Tm) of laminated ethylene vinyl acetate(EVA) and of the backsheet on the PV module. It is found that the backsheet does not peel off below the Tm of ethylene of EVA, while the PE layer of the backsheet remains on the surface of the PV module above the Tm of the PE. Thus, the backsheet is best removed at a temperature between the Tm of ethylene and that of PE layer.

In recent years, solar cells based on crystalline silicon(c-Si) have accounted for much of the photovoltaic industry. The recent studies have focused on fabricating c-Si solar modules with low cost and improved efficiency. Among many suggested methods, a photovoltaic module with a shingled structure that is connected to a small cut cell in series is a recent strong candidate for low-cost, high efficiency energy harvesting systems. The shingled structure increases the efficiency compared to the module with 6 inch full cells by minimizing optical and electrical losses. In this study, we propoese a new Conductive Paste (CP) to interconnect cells in a shingled module and compare it with the Electrical Conductive Adhesives (ECA) in the conventional module. Since the CP consists of a compound of tin and bismuth, the module is more economical than the module with ECA, which contains silver. Moreover, the melting point of CP is below 150 ℃, so the cells can be integrated with decreased thermal-mechanical stress. The output of the shingled PV module connected by CP is the same as that of the module with ECA. In addition, electroluminescence (EL) analysis indicates that the introduction of CP does not provoke additional cracks. Furthermore, the CP soldering connects cells without increasing ohmic losses. Thus, this study confirms that interconnection with CP can integrate cells with reduced cost in shingled c-Si PV modules.

Floating PV generation system, renewable energy power plant, is able to overcome the disadvantages of ground PV generation system and improve generating efficiency. The frame structural system is an established technology among a diversity of structural technologies which has been developed for related fields. In this paper, the both structural safety and characteristics of floating PV generation structures depend on the different placement angle of solar module are investigated to improve the commercial viability, the structural safety, and characteristics of floating PV generation structures. In addition, for the estimation of structural safety, FE analyses are conducted. From the results, the lower placement angle of solar module improves the structural safety of floating PV generation system.

태양광 발전시스템은 태양복사에너지를 반도체의 광전효과를 이용하여 전기에너지로 직접 전환시키는 에너지변환 시스템이다. 태양전지의 내구성과 에너지변환율에 영향을 미치는 핵심소재로는 다층형 필름구조를 갖는 백시트를 들 수 있다. 대표적인 상용 백시트는 고내구성 poly(vinyl fluoride) (PVF) 필름이 중심축에 위치하고 가격저감을 위해 도입된 poly(ethylene terephthalate) (PET) 필름이 그 양쪽에 접합된 삼층구조로 구성된다. 하지만, PVF 필름의 높은 가격은 저렴한 고내구성 백시트 를 요구하는 시장상황을 반영하기 어렵게 한다. 이를 위한 해결책으로는 PVF 필름을 결정성 PET 필름으로 대체한 탄화수소계 백시트가 될 수 있다. 하지만, PET 필름의 본질적인 가수분해에 대한 취약성으로 인해, 추가적인 수분에 대한 배리어성 부여 는 필수적이다. 이를 위해 본 연구에서는 소수성 실리카 나노입자 분산기술을 활용한 수분차단성 폴리우레탄 접착제를 개발 코자 하였다. 개발된 접착제는 내부에 위치한 PET 필름으로의 수분침투를 약화시켜, 가수분해속도를 지연시킬 것이라 기대 되었다. 본 개념의 효용성을 확인하기 위해, 표준화된 온습도조건에 노출된 이후의 일반접착제와 수분차단성 접착제가 도입 된 백시트의 기계적 강도 및 시간당 태양전지성능 변화가 비교평가되었다.

In this paper, we present the result of investigations pertaining to the development of links between unit modules of the floating type photovoltaic energy generation system made of Pultruded FRP. Since the FRP has an excellent corrosion-resistance and high specific strength and stiffness, the FRP material may be highly appreciated for the development of the floating type photovoltaic energy generation system. we discussed the development concepts of the link between unit module of floating type photovoltaic energy generation system made of PFRP, tire, and synthetic fiber, briefly. The floating type photovoltaic energy generation system linked between unit modules is installed successfully at sea site.

This study presents the tracker structural composition system for the effective angle variation of solar module. Also, the structural performance is evaluated through the structural modelling and analysis and the field application is considered.