scholarly journals Characterization and modeling of solar radiation on the ground, application to the estimate of solar potential available on the coast of Nouakchott

2019 ◽  
Vol 4 (1) ◽  
Author(s):  
A. Sidibba ◽  
D. Ndiaye ◽  
S. Bouhamady ◽  
M. El Bah

The purpose of this work is to evaluate four empirical models developed in literature such as Ghouard, Perrin Brichambaut, Bird and Hulstrom and Dependent model of the Link trouble factor. The validation of these different theoretical models was carried out using solar global radiation data collected on the Cheikh Zayed Nouakchott power plant. These measurements were carried out at a time step of 5 minutes during the period of one year. (April 1, 2015 to March 31, 2016). The results show that the Ghouard model presents notable performances compared to the other models, with a determination coefficient of 96.2%. This validation also shows that the solar radiation measured and that estimated by the different models have the same pace and have good performance with a coefficient of determination greater than 93%. The available solar potential estimation was carried out using the actual measurements collected on the Cheikh Zayed plant. The results obtained showed that the available solar potential is 5 kWh / m² / d.

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Boluwaji M. Olomiyesan ◽  
Onyedi D. Oyedum

In this study, the performance of three global solar radiation models and the accuracy of global solar radiation data derived from three sources were compared. Twenty-two years (1984–2005) of surface meteorological data consisting of monthly mean daily sunshine duration, minimum and maximum temperatures, and global solar radiation collected from the Nigerian Meteorological (NIMET) Agency, Oshodi, Lagos, and the National Aeronautics Space Agency (NASA) for three locations in North-Western region of Nigeria were used. A new model incorporating Garcia model into Angstrom-Prescott model was proposed for estimating global radiation in Nigeria. The performances of the models used were determined by using mean bias error (MBE), mean percentage error (MPE), root mean square error (RMSE), and coefficient of determination (R2). Based on the statistical error indices, the proposed model was found to have the best accuracy with the least RMSE values (0.376 for Sokoto, 0.463 for Kaduna, and 0.449 for Kano) and highest coefficient of determination, R2 values of 0.922, 0.938, and 0.961 for Sokoto, Kano, and Kaduna, respectively. Also, the comparative study result indicates that the estimated global radiation from the proposed model has a better error range and fits the ground measured data better than the satellite-derived data.


2018 ◽  
Vol 33 (2) ◽  
pp. 238-246
Author(s):  
João Rodrigo de Castro ◽  
Santiago Vianna Cuadra ◽  
Luciana Barros Pinto ◽  
João Marcelo Hoffmann de Souza ◽  
Marcos Paulo dos Santos ◽  
...  

Abstract The objective of this study was to evaluate the use of estimated global solar radiation data in the simulations of potential yield of irrigated rice. Global solar radiation was estimated by four empirical models, based on air temperature, and a meteorological satellite derivated. The empirical models were calibrated and validated for 10 sites, representative of the six rice regions of the State of Rio Grande do Sul - Brazil. To evaluate the impact of the radiation estimates on irrigated rice yield simulations, the CERES-Rice model, calibrated for four cultivars, was used. The estimates of global solar radiation of the empirical models based on the air temperature showed deviations, from the observed values, of 20 to 30% and the estimated by satellite deviations of more than 30%. The global solar radiation data estimated by the Hargreaves and Samani, Donatelli and Campbell and derived satellite (PowerNasa) type air temperature-based empirical models can be used as input data in simulation models of crop growth, development and productivity of irrigated rice.


Author(s):  
Jianhua Fan ◽  
Zhiyong Tian ◽  
Simon Furbo ◽  
Weiqiang Kong ◽  
Daniel Tschopp

Solar radiation data is necessary for the design of solar heating systems and used to estimate the thermal performance of solar heating plants. Compared to global irradiance, the direct beam component shows much more variability in space and time. The global radiation split into beam and diffuse radiation on collector plane is important for the evaluation of the performance of different collector types and collector field designs.


Author(s):  
Muchamad Rizky Nugraha ◽  
Andi Adriansyah

<span>Solar energy is a result of the nuclear fusion process in the form of a series of thermonuclear events that occur in the Sun's core. Solar radiation has a significant impact on the lives of all living things on earth. The uses, as mentioned earlier, are when the solar radiation received requires a certain amount and vice versa. As a result, a more accurate instrument of solar radiation is required. A specific instrument is typically used to measure solar radiation parameters. There are four solar radiation parameters: diffusion radiation, global radiation, direct radiation, and solar radiation duration. Thus, it needs to use many devices to measure radiation data. The paper designs to measure all four-radiation data by pyranometer with particular modification and shading device. This design results have a high correlation with a global standard with a value of R=0.73, diffusion with a value of R=0.60 and a sufficiently strong direct correlation with a value of R=0.56. It can be said that the system is much simpler, making it easier to monitor and log the various solar radiation parameters.</span>


2008 ◽  
Vol 47 (4) ◽  
pp. 1006-1016 ◽  
Author(s):  
Guang-Yu Shi ◽  
Tadahiro Hayasaka ◽  
Atsumu Ohmura ◽  
Zhi-Hua Chen ◽  
Biao Wang ◽  
...  

Abstract Solar radiation is one of the most important factors affecting climate and the environment. Routine measurements of irradiance are valuable for climate change research because of long time series and areal coverage. In this study, a set of quality assessment (QA) algorithms is used to test the quality of daily solar global, direct, and diffuse radiation measurements taken at 122 observatories in China during 1957–2000. The QA algorithms include a physical threshold test (QA1), a global radiation sunshine duration test (QA2), and a standard deviation test applied to time series of annually averaged solar global radiation (QA3). The results show that the percentages of global, direct, and diffuse solar radiation data that fail to pass QA1 are 3.07%, 0.01%, and 2.52%, respectively; the percentages of global solar radiation data that fail to pass the QA2 and QA3 are 0.77% and 0.49%, respectively. The method implemented by the Global Energy Balance Archive is also applied to check the data quality of solar radiation in China. Of the 84 stations with a time series longer that 20 yr, suspect data at 35 of the sites were found. Based on data that passed the QA tests, trends in ground solar radiation and the effect of the data quality assessment on the trends are analyzed. There is a decrease in ground solar global and direct radiation in China over the years under study. Although the quality assessment process has significant effects on the data from individual stations and/or time periods, it does not affect the long-term trends in the data.


Nativa ◽  
2019 ◽  
Vol 7 (6) ◽  
pp. 693 ◽  
Author(s):  
Érico Tadao Teramoto ◽  
Darllan Collins da Cunha e Silva ◽  
Cícero Manoel Dos Santos ◽  
Levi Pompermayer Machado ◽  
João Francisco Escobedo

O conhecimento do potencial solar é considerado uma informação essencial no dimensionamento e simulação do desempenho de sistemas que convertem radiação solar em energia elétrica ou calor disponível em fluídos, bem como em estudos agrícolas voltados ao manejo de irrigação e avaliação da produtividade potencial. Nem sempre as informações sobre a radiação solar incidente estão disponíveis e, por isso, torna-se importante o desenvolvimento de métodos capazes de estimar com acurácia a radiação solar. O presente estudo avaliou o desempenho de diferentes métodos de estimativa da radiação solar global (RG) em ambiente subtropical úmido brasileiro, a fim de determinar qual deles apresenta maior acurácia. As bases de dados meteorológicos utilizadas foram registradas pela estação meteorológica automática pertencente ao Instituto Nacional de Meteorologia (INMET) e instalada em Iguape, município localizado na porção paulista do Vale do Ribeira. Modelos empíricos foram calibrados e tomados como referência na avaliação do desempenho da Máquina de Vetores de Suporte (SVM) utilizando diferentes conjuntos de variáveis de entrada. Dentre os métodos testados, a SVM utilizando o conjunto de varáveis de entrada {R0, Tmax, Tmin, es max, es min} apresentou o melhor desempenho.Palavras-chave: modelos empíricos; Vale do Ribeira; SVM. ESTIMATING DAILY GLOBAL RADIATION FROM COMMON METEOROLOGICAL VARIABLES IN A HUMID SUBTROPICAL ENVIRONMENT  ABSTRACT: Knowledge of solar potential is essential in the design and simulation of systems that convert solar radiation in electric power or available heat in fluids, as well as in agricultural studies focused on irrigation management and potential productivity assessment. Oftentimes, information about solar radiation are not available and, therefore, it becomes important the development of methods for obtain reliable data of solar radiation. The present study evaluated the performance of different methods of estimating global solar radiation (RG) in a Brazilian humid subtropical environment in order to determine which is more accurate. The meteorological databases used were registered by the automatic meteorological station belonging to the National Institute of Meteorology (INMET) and installed in Iguape, a municipality located in the São Paulo portion in the Ribeira Valley. Empirical models were calibrated and taken as reference in the performance evaluation of the Support Vector Machine (SVM) using different sets of input variables. Among the tested methods, the SVM using the set of input variables {R0, Tmax, Tmin, esmax, es min} presented the best performance.Keywords: empirical models; Ribeira Valley, SVM.


2014 ◽  
Vol 699 ◽  
pp. 564-569 ◽  
Author(s):  
Mohd Irwan Yusoff ◽  
Muhamad Irwanto ◽  
Safwati Ibrahim ◽  
Gomesh Nair ◽  
Syed Idris Syed Hassan ◽  
...  

This paper presents the forecasting of solar radiation in Kelantan, Eastern Malaysia for the year of 2011 using Hargreaves model. This estimation is based on latitude and daily minimum and maximum temperature in Kelantan. The measured and estimated solar radiation data were compared for the year 2011 and analyzed using coefficient of residual mass (CRM), root mean squared error (RMSE), coefficient of determination (R2) and percentage error (e). The results showed that the value ofCRMis 0.09, it indicates the tendency of the estimation model to under-estimate the measure solar radiation. Meanwhile, the value ofRMSEis 8.21% and the value ofR2is 0.8661, closed to 1 indicates that about 86.61% of the total variation is explained in the data. For thee, the value is 7.98%, it indicates that the model estimation is good.


2017 ◽  
Vol 5 (2) ◽  
pp. 106
Author(s):  
Samuel Nwokolo ◽  
Julie Ogbulezie

Several empirical models have been fitted in literature for estimating global solar radiation across the globe in order to produce global solar radiation data and also as a baseline for further scientific and environmental research without the substantial cost of instrumental network that would otherwise be needed. However, peers and researchers have reported that the most commonly employed parameter for predicting global solar radiation is sunshine duration as a result of its availability and simplicity in course of measurement globally. In this research, the author considered the performance of 63 sunshine-based models for the prediction of global solar radiation at Lagos, Nigeria. Numerous models are found unreliable for use in this location, and others vary in performance. On the whole, the best model was identified due to its values of statistical indicators.


2019 ◽  
Vol 13 (1) ◽  
pp. 43-55
Author(s):  
D. O. Akpootu ◽  
A. M. Rabiu

Background:Estimation of tropospheric radio refractivity is significant in the planning and design of terrestrial communication links.Methods:In this study, the monthly average daily atmospheric pressure, relative humidity and temperature data obtained from the National Aeronautics and Space Administration (NASA) during the period of twenty two years (July 1983 - June 2005) for Osogbo (Latitude 7.470N, Longitude 4.290E, and 302.0 m above sea level) were used to estimate the monthly tropospheric radio refractivity. The monthly average daily global solar radiation with other meteorological parameters was used to developed one, two, three and four variable correlation(s) tropospheric radio refractivity models for the location. The accuracy of the proposed models are validated using statistical indicator of coefficient of determination (R2), Mean Bias Error (MBE), Root Mean Square Error (RMSE), Mean Percentage Error (MPE), Nash - Sutcliffe Equation (NSE) and Index of Agreement (IA).Results:In each case one empirical model was recommended based on their exceptional performances after ranking, except for the two variation correlations with two empirical models. The recommended models were further subjected to ranking from which the three variable correlations model that relates the radio refractivity with the absolute temperature, relative humidity and global solar radiation was found more suitable for estimating tropospheric radio refractivity for Osogbo with R2= 100.0%, MBE = -0.2913 N-units, RMSE = 0.3869 N-units, MPE = 0.0811%, NSE = 99.9999% and IA = 100.00%.Conclusion:The newly developed recommended models (Equations 16c, 17d, 17f, 18d and 19) can be used for estimating daily and monthly values of tropospheric radio refractivity with higher accuracy and has good compliance to highly varying climatic conditions for Osogbo and regions of similar climatic information.


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