scholarly journals Simulation of Water Vapor Ingress into PV-Modules under Different Climatic Conditions

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Philip Hülsmann ◽  
Markus Heck ◽  
Michael Köhl

This work deals with the simulation of water vapor ingress into wafer-based PV-modules for long-term exposure under different climatic conditions. Measured material parameters together with climatic data sets from four test sites (tropic, moderate, alpine, and arid) were used to calculate the water concentration inside of the encapsulant between solar cell and glass for a lifetime of 20 years. Two back-sheet materials (PET-based and PA-based) combined with EVA as encapsulant were used in respect to their influence on water ingress. The results show faster water ingress for warmer regions, but the highest concentrations were found for the moderate test site. The water ingress was additionally influenced by the used encapsulant and back-sheet combination. In particular the temperature dependency of the mass transfer, which differs from material to material, was the focus of this investigation.

2000 ◽  
Vol 1699 (1) ◽  
pp. 151-159 ◽  
Author(s):  
Chung-Lung Wu ◽  
Gonzalo R. Rada ◽  
Aramis Lopez ◽  
Yingwu Fang

To provide accurate climatic data for pavements under the Long-Term Pavement Performance (LTPP) Program, a climatic database was developed in 1992 and subsequently revised and expanded in 1998. In the development of this database, up to five nearby weather stations were selected for each test site. Pertinent weather data for the selected weather stations were obtained from the U.S. National Climatic Data Center and the Canadian Climatic Center. With a 1/ R2 weighting scheme, site-specific climatic data were derived from the nearby weather station data. The derived data were referred to as “virtual”weather data. To evaluate the effect of environmental factors on pavement performance and design, automated weather stations (AWS) were installed at LTPP Specific Pavement Study Projects 1, 2, and 8 to collect on-site weather data. Since the virtual weather data were developed for all LTPP test sites and will be used for future pavement performance studies, it is essential that the derived virtual data be accurate and representative of the actual onsite climatic conditions. The availability of the AWS weather data has provided an opportunity to evaluate whether virtual weather data can be used to represent on-site weather conditions. Daily temperature data and monthly temperature and precipitation data were used in this experiment. On the basis of the comparisons made between the virtual and onsite measured (AWS) data, it appears that climatic data derived from nearby weather stations using the 1/R2 weighting scheme estimate the actual weather data reasonably well and thus can be used to represent on-site weather conditions in pavement research and design.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sarah Pederzani ◽  
Vera Aldeias ◽  
Harold L. Dibble ◽  
Paul Goldberg ◽  
Jean-Jacques Hublin ◽  
...  

AbstractExploring the role of changing climates in human evolution is currently impeded by a scarcity of climatic information at the same temporal scale as the human behaviors documented in archaeological sites. This is mainly caused by high uncertainties in the chronometric dates used to correlate long-term climatic records with archaeological deposits. One solution is to generate climatic data directly from archaeological materials representing human behavior. Here we use oxygen isotope measurements of Bos/Bison tooth enamel to reconstruct summer and winter temperatures in the Late Pleistocene when Neandertals were using the site of La Ferrassie. Our results indicate that, despite the generally cold conditions of the broader period and despite direct evidence for cold features in certain sediments at the site, Neandertals used the site predominantly when climatic conditions were mild, similar to conditions in modern day France. We suggest that due to millennial scale climate variability, the periods of human activity and their climatic characteristics may not be representative of average conditions inferred from chronological correlations with long-term climatic records. These results highlight the importance of using direct routes, such as the high-resolution archives in tooth enamel from anthropogenically accumulated faunal assemblages, to establish climatic conditions at a human scale.


2017 ◽  
Vol 13 (1) ◽  
pp. 42-51 ◽  
Author(s):  
Daniela Štaffenová ◽  
Ján Rybárik ◽  
Miroslav Jakubčík

AbstractThe aim of experimental research in the area of exterior walls and windows suitable for wooden buildings was to build special pavilion laboratories. These laboratories are ideally isolated from the surrounding environment, airtight and controlled by the constant internal climate. The principle of experimental research is measuring and recording of required physical parameters (e.g. temperature or relative humidity). This is done in layers of experimental fragment sections in the direction from exterior to interior, as well as in critical places by stable interior and real exterior climatic conditions. The outputs are evaluations of experimental structures behaviour during the specified time period, possibly during the whole year by stable interior and real exterior boundary conditions. The main aim of this experimental research is processing of long-term measurements of experimental structures and the subsequent analysis. The next part of the research consists of collecting measurements obtained with assistance of the experimental detached weather station, analysis, evaluation for later setting up of reference data set for the research locality, from the point of view of its comparison to the data sets from Slovak Hydrometeorological Institute (SHMU) and to localities with similar climate conditions. Later on, the data sets could lead to recommendations for design of wooden buildings.


Coatings ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 49 ◽  
Author(s):  
Kensuke Nishioka ◽  
So Pyay Moe ◽  
Yasuyuki Ota

Not all sunlight irradiated on the surface of a photovoltaic (PV) module can reach the cells in the PV module. This loss reduces the conversion efficiency of the PV module. The main factors of this loss are the reflection and soiling on the surface of the PV module. With this, it is effective to have both antireflection and antisoiling effects on the surface of PV modules. In this study, the antireflection and antisoiling effects along with the long-term reliability of the silica-based layer easily coated on PV modules were assessed. A silica-based layer with a controlled thickness and refractive index was coated on the surface of a Cu(In,Ga)Se2 PV array. The array was exposed outdoors to assess its effects and reliability. As a result of the coating, the output of the PV array increased by 3.9%. The environment of the test site was relatively clean and the increase was considered to be a result of the antireflection effect. Moreover, it was observed that the effect of the coating was maintained without deterioration after 3.5 years. The coating was also applied to a silicon PV module and an effect similar to that of the CIGS PV module was observed in the silicon PV module.


2021 ◽  
Author(s):  
Cyrine Chenaoui ◽  
Slimane Ben Miled ◽  
Mamadou Sadio Ndongo ◽  
Papa Ibrahima Ndiaye ◽  
Mourad Rekik ◽  
...  

AbstractThe distribution of ticks is essentially determined by the presence of climatic conditions and ecological contexts suitable for their survival and development.We have developed a general tick biology model to study the major trends due to climate change on tick population dynamics under different climate conditions.We build a model that explicitly takes into account stage into each physiological state through a system of infinite differential equations where tick population density are structured on an infinite discrete set. We suppose that intrastage development process is temperature dependent (Arrhenius temperatures function) and that larvae hatching and adult mortality are temperature and precipitations dependent.We analysed mathematically the model and have explicit the R0 of the tick population. Therefore, we performed a numerical analysis of the model under three different climate conditions (tropical, Mediterranean and subarctic climates) over the short term using climatic data from 1995 to 2005, as well as long-term simulations from 1902 to 2005.


2011 ◽  
Vol 8 (3) ◽  
pp. 5891-5915 ◽  
Author(s):  
S. Bastola ◽  
C. Murphy ◽  
J. Sweeney

Abstract. Conceptual hydrological models are widely used for climate change impact assessment. The implicit assumption in most such work is that the parameters estimated from observations remain valid for future climatic conditions. This paper evaluates a simple threshold based approach for testing this assumption, where a set of behavioural simulators are identified for different climatic conditions for the future simulation i.e. wet, average and dry conditions. These simulators were derived using three different data sets that are generated by sampling a block of one year of data without replacement from the observations such that they define the different climatic conditions. The simulators estimated from the wet climatic data set showed the tendency to underestimate flow when applied to dry data set and vice versa. However, the performances of the three sets of basin simulators on chronologically coherent data are identical to the simulators identified from a sufficiently long data series that contains both wet and dry climatic conditions. The results presented suggest that the issue of time invariance in the value of parameters has a minimal effect on the simulation if the change in precipitation is less than 10 % of the data used for calibration.


2020 ◽  
Vol 172 ◽  
pp. 01005
Author(s):  
Naomi Grint ◽  
Clifford A. Elwell

This work addresses the need for long-term, high-resolution, in-situ datasets by providing in-wall humidity and temperature data from three walls of in-use office buildings over three to four years, two of which were insulated during this period. Temperature and humidity sensors were inserted diagonally into three locations within the thick brick walls, and the holes were carefully packed with dry brick dust. Surface, ambient and interstitial measurements were also recorded, as were additional climatic data during 18 months at one wall, and in-wall moisture content using resistance pins for 18 months in another. This dataset is unique due to the combination of temporal length and resolution, spatial detail, as well as the availability of control data from both before and after insulation and the use of real climatic conditions on both sides of the walls. The experiment was designed to produce data to facilitate parameter estimation by inverse analysis. By using these estimated parameters, or by taking material property measurements, it would also be useful for validating and calibrating hygrothermal models, and by using plausible ranges for parameters it is useful for exploring model performance, such as through sensitivity analyses.


2020 ◽  
Vol 162 ◽  
pp. 285-295 ◽  
Author(s):  
Divine Atsu ◽  
Istvan Seres ◽  
Mohammadreza Aghaei ◽  
Istvan Farkas

2001 ◽  
Vol 6 (2) ◽  
pp. 3-14 ◽  
Author(s):  
R. Baronas ◽  
F. Ivanauskas ◽  
I. Juodeikienė ◽  
A. Kajalavičius

A model of moisture movement in wood is presented in this paper in a two-dimensional-in-space formulation. The finite-difference technique has been used in order to obtain the solution of the problem. The model was applied to predict the moisture content in sawn boards from pine during long term storage under outdoor climatic conditions. The satisfactory agreement between the numerical solution and experimental data was obtained.


Author(s):  
Laima TAPARAUSKIENĖ ◽  
Veronika LUKŠEVIČIŪTĖ

This study provides the analysis of drought conditions of vegetation period in 1982-2014 year in two Lithuanian regions: Kaunas and Telšiai. To identify drought conditions the Standardized Precipitation Index (SPI) was applied. SPI was calculated using the long-term precipitation record of 1982–2014 with in-situ meteorological data. Calculation step of SPI was taken 1 month considering only vegetation period (May, June, July, August, September). The purpose of investigation was to evaluate the humidity/aridity of vegetation period and find out the probability of droughts occurrence under Lithuanian climatic conditions. It was found out that according SPI results droughts occurred in 14.5 % of all months in Kaunas region and in 15.8 % in Telšiai region. Wet periods in Kaunas region occurred in 15.8 %, and in Telšiai region occurrence of wet periods was – 18.8 % from all evaluated months. According SPI evaluation near normal were 69.7 % of total months during period of investigation in Kaunas and respectively – 65.5 % in Telšiai. The probability for extremely dry period under Lithuania climatic conditions are pretty low – 3.0 % in middle Lithuania and 2.4 % in western part of Lithuania.


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