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The purpose of this paper is to predict the global solar radiation intensity in areas where meteorological stations do not exist and information on solar radiation cannot be obtained experimentally.

The approach to achieve the objective of the paper is developing multiple regression relations between the global solar radiation intensity (the dependent variable) and geographical, geometrical, astronomical and meteorological parameters (the independent variables). The independent variables used for this purpose were selected based on their ease of measurability outside the meteorological station and without expensive equipment. The number of independent variables is arbitrarily chosen and directly affects the accuracy of predictions.

Linear regression relations using one, two, three, four, five, six, and seven independent variables were developed to predict the global solar radiation intensity on horizontal surfaces. An advanced computer program based on least square analysis was used to obtain the regression coefficients. The relations having the highest correlation coefficients were selected. The study shows even when only one independent variable (declination angle) is used, the one variable regression relation predicts the global solar radiation with an accuracy that is satisfactory in most engineering applications.

The diversity of regression relations introduced in this paper gives the engineer such a broad freedom of choice, that knowing only an astronomical parameter of the site makes him capable of estimating the global solar radiation intensity within acceptable margins. The predicted values of global solar radiation intensity by this approach can be used for the design and performance estimation in solar applications. The statistical model developed in this research was validated when compared with the measured data in Yazd airport. The measured data used to analyze the model equations were collected in a 13‐year period. No investigation of this type exists having such degree of accuracy in geographical, geometrical, astronomical and meteorological parameters in Iran.

The objective is to provide a quantitative insight on the dynamic nature of insolation on the building perimeter according to location, season and orientation. Such understanding is necessary for deciding on solar control strategies in diverse climatic environments, from low to high availability of insolation.

This study explores the seasonal changes of solar irradiation on building façades of various orientations at five locations with diverse climates (Reykjavík, London, Athens, Riyadh, Lagos). Solar data collected from the European PVGIS database is used to study the monthly distribution of global solar radiation incident on building façades at cardinal and ordinal orientations, as well as the proportions of its components.

The results illuminate the effects of the various factors on insolation. Among others: In all locations, horizontal surfaces receive more annual irradiation than any façade. In summer, east/west facades receive more radiation than south, hence solar protection on those directions is more important than on south. The beam fraction varies seasonally on south and north facades, but not so on east/west. Local atmospheric conditions can offset the importance of latitude on insolation levels and composition.

The paper utilises commonly available data to correlate insolation values and types under different factors across the globe, offering a better understanding on insolation for the design of greener buildings.

The purpose of this study is to evaluate the reliability of the technique for estimating solar radiation in areas of rough topography and to detect the source of error and means for improvement.

Spatial data of the study area in the form of digital elevation model (DEM) coupled with geographic information system (GIS) were used to estimate the monthly solar radiation at locations with rough topography. The generated data were compared with measured data collected from all the selected locations using NASA data.

The results show that the variation in topographic parameters has a strong influence on the amount of solar radiation received by two close locations. However, the method performed well for solar radiation estimated in the areas of rough topography.

The proposed approach overestimates the monthly solar radiation as compared with NASA data due to the impact of topographic parameters accounted for by the model which are not accounted by conventional methods of measurements. This approach can be improved by incorporating the reflected component of radiation in the model used to estimate the solar radiation implemented in the GIS.

The approach of using GIS with DEM to estimate solar radiation enables to identify the spatial variability in solar radiation between two closest locations due to the influence of topographic parameters, and this will assist in proper energy planning and decision making for optimal areas of solar photovoltaic installation.

Using modeling approaches, this paper aims to propose different mathematical models for estimating the different components of the solar radiation as well as the received solar energy by a collector.

In this article, the authors consider three mathematical models to estimate the solar radiation captured at ground level by a solar collector. These models are Capderou model, Liu & Jordan model and R.sun model. In the context of the design of experiments, we performed measurements of solar radiation received by a collector using a pyranometer. The obtained measurements were compared with the three mathematical models.

The comparison enabled the subsequent evaluation to determine the most appropriate model that best fit for our region. As a result, the Capderou model reveals to be the most suitable for our region.

Estimation of solar radiation at ground level (received by a collector) is of paramount importance for the design and optimization of solar energy systems. Nevertheless, many factors influence the amount of energy received by a collector situated at a ground, such as the longitude of the location, latitude, altitude, tilt collector orientation, temperature and humidity of the environment, wind speed, etc. Because of the complex influence of these parameters, the received solar radiation by the collector is a dynamical and a random process.

This paper aims to propose an approach based on physical model integration for surface and cloud albedo computation using an approximate form of the atmospheric radiative transfer equation and sun-pixel-satellite.

The data used in this study are global irradiance collected from for various sites in Algeria, and data were obtained from the processing of the high-resolution visible images taken by the Meteosat Second Generation satellite in 2010.

The results suggest that the standard deviation obtained with this method is similar to that obtained with current estimation methods. The hourly and daily correlation coefficients range between 0.95 and 0.97 and between 0.97 and 0.99, respectively. The hourly and daily mean bias errors range between −0.2 and +1.2 per cent and between −0.2 and +1.4 per cent, respectively. The hourly and daily root mean square errors range between 10 and 17 per cent and between 4 and 8 per cent, respectively.

This paper developed a new estimating method that derives the hourly global horizontal solar irradiation at a ground level from geostationary satellite data under local climate conditions.

Knowledge of the local solar radiation is important for many applications of solar energy systems. The global solar radiation on horizontal surface at the location of interest is the most critical input parameter employed in the design and prediction of the performance of solar energy systems. In this study, 3 empirical sunshine based models are compared correlating the monthly mean daily global solar radiation on a horizontal surface with monthly mean sunshine records for Nigde, Turkey. Models are compared using coefficient of determination (R²), the root mean square error (RMSE), the mean bias error (MBE) and the t-statistic. According to our results, all the models fitted the data adequately and can be used to estimate the specific monthly global solar radiation. The t-statistic was used as the best indicator; this indicator depends on both, and is more effective for determining the model performance. The agreement between the estimated and the measured data were remarkable and the method was recommended for use in Nigde, Turkey.

The purpose of this paper is to investigate a wall-integrated solar chimney for passive ventilation of a building cavity. Ventilation is required to improve the circulation of air in the built environment. This can be achieved through natural or forced convection. Natural circulation can be driven by renewable energy, and so it promotes sustainable exploitation of energy resources. Solar energy is one of the promising renewable energy resources.

The chimney was designed to face the Equator on the wall of a room which required ventilation. Mean monthly daily heating and cooling loads of the room were computed with and without a solar chimney by using hourly meteorological data from nine different weather sites at low, medium and high latitudes. The chimney was implemented with and without airflow control, and simulated by using the ESP-r software.

Results show that the solar chimney with airflow control marginally reduced the heating load in the building envelope, with a similar effect being exhibited by the chimney with uncontrolled airflow. The cooling load was reduced by the controlled airflow at all the nine sites. In contrast, the uncontrolled airflow increased the cooling load at some sites. In addition, the chimney with airflow control reduced the annual total thermal load at all the sites, while the chimney with uncontrolled airflow raised the total thermal load at some locations.

The performance of solar chimneys designed with and without airflow control systems has been investigated under the same prevailing meteorological conditions at a given site. Findings show that controlling airflow in a solar chimney reduces the total thermal load in the built environment. This information can be applied in different parts of the world.

The malfunction variables of power stations are related to the areas of weather, physical structure, control and load behaviour. To predict temporal power failure is difficult due to their unpredictable characteristics. As high accuracy is normally required, the estimation of failures of short-term temporal prediction is highly difficult. This study presents a method for converting stochastic behaviour into a stable pattern, which can subsequently be used in a short-term estimator. For this conversion, K-means clustering is employed, followed by Long-Short-Term Memory (LSTM) and Gated Recurrent Unit (GRU) algorithms are used to perform the Short-term estimation. The environment, the operation and the generated signal factors are all simulated using mathematical models. Weather parameters and load samples have been collected as part of a data set. Monte-Carlo simulation using MATLAB programming has been used to conduct experimental estimation of failures. The estimated failures of the experiment are then compared with the actual system temporal failures and found to be in good match. Therefore, for any future power grid, there is a testbed ready to estimate the future failures.

The presence of broken clouds leads to frequent fluctuations in direct normal incident solar irradiation as well as diffuse radiation from the sky. This brings a lot of challenge for grid integration of solar power plants. The paper aims to discuss this issue.

A new model is presented to nowcast solar radiation by utilizing hourly global horizontal irradiance (GHI) over a large spatial grid. The spatial distribution of the GHI provides information on the presence of a cloud shadow above a given site. This information is extracted with the help of various data processing techniques. The spatial–temporal data analysis is employed to track the extracted cloud shadow image based on a dynamic model. A Kalman filter is applied for the assimilation of data in the tracking of the extracted shadow over a geographical location.

The proposed model can provide very good forecasting of solar radiation for various time horizons. However, the variation of shadow features between time steps must be included in the dynamic model to forecast accurate GHI values.

In this paper database used is on hourly basis; it can be further improved for the inter-hour level of ground data for more accuracy.

The outcome of this paper would be useful in the field of solar energy application and for weather monitoring purposes.

The forecasted position of the shadow is utilized to prepare and forecast a GHI map for one hour time horizon. Results show that the model can be utilized to forecast solar radiation with accuracy consistent with the contemporary models.

The purpose of this paper is to determine the optimum temperature and solar radiation periods from November 2008 to April 2009.

Four flat plate collectors were constructed and inclined at an angle ß = 0o, Φ°, (Φ + 15)o and (Φ − 15)° tilt angles where Φ is the latitude of the location (12.1o). The tests were conducted for a period of six months spanning from November 2008 to April 2009. Readings were taken for solar radiation, absorber surface temperature and ambient temperature from 10 a.m. to 3 p.m. on an hourly basis. The amount of solar energy in W/m2 for Kano metropolis, which lies on latitude 12.1°, was determined experimentally.

It was observed that the maximum temperature was 100°C, and it falls in April at the 12.1° tilt angle followed by 99.9°C and 99.8°C at –2.9° and 0°, respectively, within same month. April is the optimum period having the highest temperature. The maximum solar radiation for the six months recorded was 1070.4 W/m2 and fell on 4th and 8th of February at the 27.1° tilt angle and the highest mean monthly solar radiation was 953.7593W/m2 in November at the 27.1° tilt angle followed by 895.7321 and 888.6286W/m2 in February at the 27.1° and 12.1° tilt angle, respectively.

The research is limited to six-month periods and Kano metropolis.

The research was carried out in the Department of Mechanical Engineering Bayero University Kano, Nigeria.