Reliability Improvement and Remaining Issues on Photovoltaic Cells and Modules

Mapping Intimacies ◽

10.1149/osf.io/suzay ◽

2020 ◽

Author(s):

Atsushi Masuda

Keyword(s):

Incident Light ◽

Photovoltaic Cells ◽

Test Methods ◽

Chemical Analyses ◽

Degradation Mechanisms ◽

Reliability Improvement ◽

Degradation Factor ◽

Physical And Chemical ◽

Acceleration Test

Degradation phenomena of photovoltaic cells and modules were systematically and in detail studied by observing those exposed outdoors and subjecting those to various indoor acceleration tests. Those degradation phenomena were roughly classified into three categories; less incident light into photovoltaic cells, less collection of photogenerated carriers, and less photovoltaic ability itself. Degradation mechanisms of photovoltaic cells and modules were clarified by microscopic physical and chemical analyses. Based on the mechanisms, it was found that key materials for improving reliability are encapsulants and electrodes. Improvement methods of reliability for photovoltaic cells and modules were also proposed. Prediction of lifetime by indoor acceleration test methods is also important although the prediction is quite difficult using the artificial test methods with only one or two degradation factor(s). Remaining issues of reliability and durability will be also presented.

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An Interactive 3-Dimensional Database Applied to the Conservation of a Painted Chapel

International Journal of Heritage in the Digital Era ◽

10.1260/2047-4970.1.2.233 ◽

2012 ◽

Vol 1 (2) ◽

pp. 233-250 ◽

Cited By ~ 6

Author(s):

Jean-Marc Vallet ◽

Livio De Luca ◽

Marie Feillou ◽

Odile Guillon ◽

Marc Pierrot-Deseilligny

Keyword(s):

Conservation Management ◽

Wall Paintings ◽

Chemical Analyses ◽

Degradation Mechanisms ◽

3 Dimensional ◽

Geometrical Complexity ◽

Restoration Techniques ◽

Scientific Documentation ◽

Physical And Chemical ◽

State Diagnosis

Matteo Giovannetti's frescoes (1355–1356) which decorate the Innocent VI chapel of La Chartreuse du Val des Bénédictins (Villeneuve-lez-Avignon, France) are very sensitive to the alteration. They need a new restoration campaign. Because of the geometrical complexity of the place, the environment and the involved degradation mechanisms, a good conservation management of these murals is essential. Therefore, an interactive 3- dimensional spatial database, including dated data was developped. Architectural measurements, digital scientific documentation were gathered. A historical documentation including restoration acts, used restoration products has been collected. Last, the paintings degradations, up-to-date deterioration patterns description and conservation state diagnosis of these wall paintings including a deterioration mapping are monitored. Results of the physical and chemical analyses of painting, restoration techniques and deterioration products are also integrated. The entire collected and interactive database will be available for conservation managers and researchers within the next three years.

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Minority carrier diffusion length determination from capacitance measurements in Se–CdO photovoltaic cells

Canadian Journal of Physics ◽

10.1139/p91-088 ◽

1991 ◽

Vol 69 (3-4) ◽

pp. 538-542 ◽

Cited By ~ 9

Author(s):

C. H. Champness ◽

Z. A. Shukri ◽

C. H. Chan

Keyword(s):

Substrate Temperature ◽

Diffusion Length ◽

Incident Light ◽

Photovoltaic Cells ◽

Minority Carrier Diffusion Length ◽

Electron Collection ◽

Straight Line ◽

Current Change ◽

Length Determination ◽

Output Capacitance

In Se–CdO photovoltaic cells, the electron diffusion length Ln in the selenium absorber layer has been determined from measurements of capacitance C and photocurrent under monochromatic illumination by variation of applied reverse bias. If penetrating incident light of band-gap wavelength is used, a plot against 1/C of the illuminated-to-dark current change ΔI yields a straight line over a certain range of bias values. Extrapolation of this line to the 1/C axis yields Ln. It was found in the fabrication of the Se–CdO cells that increasing the substrate temperature from 100 to 140 °C during the selenium deposition resulted in an increase in the cell photovoltaic output. Capacitance and ΔI measurements on these cells showed an increase in diffusion length with substrate temperature, indicating that the increased cell performance was due to improved electron collection in the selenium layer.

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Nanostructured Bitumen with Nanocarbon

Eurasian Chemico-Technological Journal ◽

10.18321/ectj888 ◽

2019 ◽

Vol 21 (4) ◽

pp. 317 ◽

Cited By ~ 1

Author(s):

B.B. Teltayev ◽

A.A. Kalybai ◽

G.G. Izmailova ◽

S.R. Rossi ◽

E.D. Amirbayev ◽

...

Keyword(s):

Low Temperature ◽

Test Methods ◽

Structure Variation ◽

Temperature Resistance ◽

Chemical Indicators ◽

Excess Surface ◽

The Cost ◽

Physical And Chemical ◽

Low Temperature Resistance

Physical and chemical indicators of bitumen quality of grade BND 70/100 with the added carbon nanopowder 2% by weight have been studied by laboratory test methods and analysis. High reaction ability of nanopowder particles and concentration of excess surface and internal energy in them have been determined, which provide the increase of low-temperature resistance, aggregate strength, and improvement of rheological properties of nanostructured bitumen. Essential structure variation has been proved: the increase of asphaltenes and oils content for 9% and 7.2% respectively due to the decrease of resins for 16.2% by weight. Methods have been discussed for preparing a liquid nanocarbon mix, adding of the mix into bitumen and homogenization of the bitumen. Some economic indicators have been represented which influence essentially the reduction for the cost value of the nanostructure bitumen.

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Use of Ashes from Biomass Combustion as an Aggregate for Concrete

Materials Science Forum ◽

10.4028/www.scientific.net/msf.958.111 ◽

2019 ◽

Vol 958 ◽

pp. 111-115

Author(s):

V.A.S. Schein ◽

G. Conte ◽

Marilena Valadares Folgueras ◽

L.V.O. Dalla Valentina ◽

M.R. Medeiros

Keyword(s):

Compressive Strength ◽

Power Plant ◽

Environmentally Friendly ◽

Biomass Combustion ◽

Chemical Analyses ◽

Structural Concrete ◽

Mixing Ratios ◽

Physical And Chemical ◽

Biomass Ashes

This paper discusses an environmentally-friendly destination for the residual ashes resulting from the firing of biomass (wood wastes) at the Engie Brasil Cogeneration Power Plant located in Lages, Santa Catarina, Brazil. The study proposes reusing the residue as a substitution for crushed stones in the production of concrete. Environmental, physical, and chemical analyses were performed for characterization of the ashes. Specimens prepared with ash and subjected to testing presented a compressive strength of around 18.63 Mpa (2700 psi), which is in compliance with the ACI-213R and ASTM C330-5 specifications. With pretreatment and proper mixing ratios, biomass ashes may be employed as an aggregate in the manufacture of lightweight structural concrete.

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