scholarly journals Simulation and design of collector array units within large systems

2019 ◽  
Author(s):  
Jianhua Fan ◽  
Zhiyong Tian ◽  
Simon Furbo ◽  
Weiqiang Kong ◽  
Daniel Tschopp
Keyword(s):  
Solar Radiation ◽  
Thermal Performance ◽  
Global Radiation ◽  
Diffuse Radiation ◽  
Solar Heating ◽  
Heating Systems ◽  
Global Irradiance ◽  
Radiation Data ◽  
Large Systems ◽  
Beam Component

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.

Measurement of Solar Radiation for Renewable Energy Systems

2008 ◽  
Author(s):  
Andrea Padovan ◽  
Davide Del Col
Keyword(s):  
Solar Radiation ◽  
Energy Systems ◽  
Diffuse Radiation ◽  
Renewable Energy Systems ◽  
Global Irradiance ◽  
Radiation Data ◽  
Inclined Surfaces ◽  
Energy Conversion Systems ◽  
Tilted Plane ◽  
Inclined Surface

In this paper the authors present a new set of solar radiation data taken at the latitude of 45.4°, in Padova, Italy. These measurements are performed within a new laboratory for the study of solar energy conversion systems. The global and the diffuse irradiance is measured on the horizontal plane and the global irradiance is also measured on sloped planes. The experimental uncertainty of the measurement of solar radiation is fully analyzed. In the design of a solar system, it is crucial to know the solar radiation on the inclined surface, but generally only data on the horizontal is available and solar radiation on the tilted plane is predicted using the information collected on the horizontal. There is need for assessment of prediction methods for estimating the solar radiation on inclined surfaces. In this paper, new data of global and diffuse radiation is compared to some most used correlations. Besides, the values calculated for the tilted plane are compared against those directly measured by a pyranometer installed on the sloped plane.

scholarly journals Solar fraction used in water heating systems for south Brazilian climate changes scenarios

2020 ◽  
Vol 42 ◽  
pp. e48583 ◽  
Author(s):  
Carolina Kratsch Sgarbossa ◽  
Jorim Sousa das Virgens Filho
Keyword(s):  
Solar Radiation ◽  
Energy Demand ◽  
Climate Changes ◽  
The State ◽  
Solar Heating ◽  
Water Heating ◽  
Heating Systems ◽  
Radiation Data ◽  
Solar Fraction ◽  
The Impact

 Solar thermal systems consist of water heating from the global solar radiation. Increasing atmospheric concentrations of greenhouse gases tend to increase the earth's surface temperature. The main objective of this work was to estimate the solar fraction obtained by means of solar heating systems for dwellings, for eight locations in the State of Paraná, in scenarios of possible climate changes projected until the end of the 21st century. F-Chart method was used to simulate the performance of solar heating systems based on the monthly average of solar radiation data, which determines the annual solar fraction or percentage of the energy demand that is covered by the solar installation. The results showed that with the impact of the climate changes, the decrease in the percentage of energy demand average that is covered by the solar installation was on average 14.3%, for both scenarios. The simulated values showed a slight decrease trend of radiation data and an increase of the solar fraction. All localities presented a characteristic seasonal behavior, with annual values of solar fraction between 82.4 and 129.8%, according to the studied localities. In relation to the monthly solar fraction, the values between November and March presented averages of solar fraction between 104 and 147.2%. But from May to August, the percentage of energy demand served by the solar installation does not reach the totality, with values between 53.6 and 99.9%. The results prove that the State of Parana has favorable climatic conditions for the installation of solar heating systems, even if it is installed for aggregation purposes, in order to reduce the electric power consumption.

Improved Accuracy Models For Hourly Diffuse Solar Radiation

2005 ◽  
Vol 128 (1) ◽  
pp. 104-117 ◽  
Author(s):  
T. Muneer ◽  
S. Munawwar
Keyword(s):  
Solar Radiation ◽  
Regression Models ◽  
Global Radiation ◽  
Diffuse Radiation ◽  
Evaluation Procedure ◽  
Accuracy Score ◽  
Error Statistics ◽  
Diffuse Solar Radiation ◽  
Energy Applications ◽  
Extensive Evaluation

Solar energy applications require readily available, site-oriented, and long-term solar data. However, the frequent unavailability of diffuse irradiation, in contrast to its need, has led to the evolution of various regression models to predict it from the more commonly available data. Estimating the diffuse component from global radiation is one such technique. The present work focuses on improvement in the accuracy of the models for predicting horizontal diffuse irradiation using hourly solar radiation database from nine sites across the globe. The influence of sunshine fraction, cloud cover, and air mass on estimation of diffuse radiation is investigated. Inclusion of these along with hourly clearness index, leads to the development of a series of models for each site. Estimated values of hourly diffuse radiation are compared with measured values in terms of error statistics and indicators like, R2, mean bias deviation, root mean square deviation, skewness, and kurtosis. A new method called “the accuracy score system” is devised to assess the effect on accuracy with subsequent addition of each parameter and increase in complexity of equation. After an extensive evaluation procedure, extricate but adequate models are recommended as optimum for each of the nine sites. These models were found to be site dependent but the model types were fairly consistent for neighboring stations or locations with similar climates. Also, this study reveals a significant improvement from the conventional k-kt regression models to the presently proposed models.

scholarly journals Comparative Study of Ground Measured, Satellite-Derived, and Estimated Global Solar Radiation Data in Nigeria

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Boluwaji M. Olomiyesan ◽  
Onyedi D. Oyedum
Keyword(s):  
Solar Radiation ◽  
Comparative Study ◽  
Global Radiation ◽  
Statistical Error ◽  
Global Solar Radiation ◽  
Coefficient Of Determination ◽  
Mean Bias Error ◽  
Percentage Error ◽  
Radiation Data ◽  
Proposed Model

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.

scholarly journals Analysis of the potential use of Trombe walls in Brazil: design recommendations

2020 ◽  
Vol 5 ◽  
pp. 4
Author(s):  
Fernando Antonio de Melo Sá Cavalcanti ◽  
Rosana Maria Caram
Keyword(s):  
Solar Radiation ◽  
Computer Simulations ◽  
Thermal Performance ◽  
Natural Ventilation ◽  
Solar Heating ◽  
Heating And Cooling ◽  
Heated Air ◽  
Trombe Wall ◽  
Potential Use ◽  
Passive Strategy

In this paper, the thermal performance of a standard environment was evaluated based on the use of a Trombe wall with different configurations and types of use, as the potential for using this passive strategy is still little studied in Brazil. This device is capable of absorbing energy from solar radiation by heating the air in this greenhouse and this heated air can be directed to the interior or exterior of the building depending on the purpose. This air can be used to heat the room or cool it by means of natural ventilation. The analysis of this research was based on a series of computer simulations using the EnergyPlus software, version 7.0 in order to quantify and classify the thermal performance of a standard environment equipped with this component, under the various construction configurations. Both for heating and cooling environments. The use of Trombe walls improved the thermal comfort of users in buildings located in Brazil, depending on the climate where they are located, promoting natural ventilation and passive solar heating, allowing the potential of this device to be investigated in the most diverse Brazilian regions.

scholarly journals Development of a solar radiation sensor system with pyranometer

2022 ◽  
Vol 12 (2) ◽  
pp. 1385
Author(s):  
Muchamad Rizky Nugraha ◽  
Andi Adriansyah
Keyword(s):  
Solar Radiation ◽  
Solar Energy ◽  
Global Radiation ◽  
Fusion Process ◽  
Direct Radiation ◽  
Radiation Data ◽  
A Value ◽  
Living Things ◽  
Radiation Sensor ◽  
Shading Device

<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>

Thermal performance improvement method for air-based solar heating systems

Solar Energy ◽  
2019 ◽  
Vol 186 ◽  
pp. 277-290 ◽  
Author(s):  
Youngjin Choi ◽  
Masayuki Mae ◽  
Hyun Bae Kim
Keyword(s):  
Performance Improvement ◽  
Thermal Performance ◽  
Solar Heating ◽  
Heating Systems ◽  
Improvement Method

scholarly journals Direct effect of aerosols on solar radiation and gross primary production in boreal and hemiboreal forests

2018 ◽  
Vol 18 (24) ◽  
pp. 17863-17881 ◽  
Author(s):  
Ekaterina Ezhova ◽  
Ilona Ylivinkka ◽  
Joel Kuusk ◽  
Kaupo Komsaare ◽  
Marko Vana ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Primary Production ◽  
Direct Effect ◽  
Gross Primary Production ◽  
Global Radiation ◽  
Diffuse Radiation ◽  
Light Use Efficiency ◽  
Diffuse Fraction ◽  
Aerosol Loading ◽  
Use Efficiency

Abstract. The effect of aerosol loading on solar radiation and the subsequent effect on photosynthesis is a relevant question for estimating climate feedback mechanisms. This effect is quantified in the present study using ground-based measurements from five remote sites in boreal and hemiboreal (coniferous and mixed) forests of Eurasia. The diffuse fraction of global radiation associated with the direct effect of aerosols, i.e. excluding the effect of clouds, increases with an increase in the aerosol loading. The increase in the diffuse fraction of global radiation from approximately 0.11 on days characterized by low aerosol loading to 0.2–0.27 on days with relatively high aerosol loading leads to an increase in gross primary production (GPP) between 6 % and 14 % at all sites. The largest increase in GPP (relative to days with low aerosol loading) is observed for two types of ecosystems: a coniferous forest at high latitudes and a mixed forest at the middle latitudes. For the former ecosystem the change in GPP due to the relatively large increase in the diffuse radiation is compensated for by the moderate increase in the light use efficiency. For the latter ecosystem, the increase in the diffuse radiation is smaller for the same aerosol loading, but the smaller change in GPP due to this relationship between radiation and aerosol loading is compensated for by the higher increase in the light use efficiency. The dependence of GPP on the diffuse fraction of solar radiation has a weakly pronounced maximum related to clouds.

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