Annual Optimum Tilt Angle Research Articles

Formulation of new correlations in terms of extraterrestrial radiation by optimization of tilt angle for installation of solar photovoltaic systems for maximum power generation: case study of 26 cities in India

This paper deals with finding of optimum tilt angle for installation of optimized solar photovoltaic system in India. The optimization of tilt angles is performed using measured solar radiation data for 26 cities in India. The tilt angle is changed from 0° to 90° at step of 1° to find out optimum tilt angle for which monthly average solar radiation is maximum. It was found that the optimum tilt angle varies between 0° and 63° throughout the year in India. The monthly optimum tilt angle is maximum in December for all cities in India. It is found that increase in maximum solar radiation at monthly optimum tilt angle in comparison to latitude based tilt angle and annual optimum tilt angle varies from 5.85% to 8.08% and 5.95% to 8.34%, respectively, showing monthly optimum tilt angle is beneficial for maximum power generation for different cities in India. The novelty of this study is new correlations of optimum tilt angle in terms of extraterrestrial radiation are developed for estimating monthly optimum tilt angle for installation of photovoltaic systems at different sites in India. The root mean square error in correlation equations varies from 0.1256 to 0.9771.

Modeling Energy Produced by Solar Panels

As solar panels become increasingly popular, consumers want to know how to harvest more of the sun’s energy and how to increase the efficiency of solar panels. Determining the annual optimum tilt angle of a solar panel is a simple yet effective way to increase the energy generated. The hypothesis was that if the tilt angle of the solar panel was set to the latitude of the location, then the solar panel would generate the most energy annually. A mathematical model was built to simulate the amount of solar energy generated in a day and in a year and was used as comparison to field data. Ten solar panels of varying angles were set outside and the voltage across a resistor was logged every five minutes to measure the energy generated by the solar panels. The model simulation supported the hypothesis, as the solar panel tilt angle of 40° generated the most energy and the latitude of the location of the experiment was around 40°. The field data supports the hypothesis at the experimental latitude and the results of the simulation confirm the field data, and shows that the solar panel tilt angle should be set within ±10° of the latitude to produce the most energy.

Study on Optimum Tilt Angles of Photovoltaic Shading Systems in Different Climatic Regions of China

Photovoltaic shading systems which can act as power generators and external shading devices in buildings have been widely used in recent years. In order to obtain the optimum tilt angles of photovoltaic shading systems in China, this paper develops a simulation model for PV shading systems based on EnergyPlus. Five cities, viz. Harbin, Beijing, Changsha, Kunming, and Guangzhou, are selected as representative cities for different climatic regions in this study. The annual and monthly optimum tilt angles of PV shading systems are investigated and analyzed for maximizing electricity generation and minimizing net energy consumption. The results show that PV shading panels installed with monthly optimum tilt angles are superior to those installed with annual optimum tilt angles. Moreover, PV panels mounted in the south orientation have larger energy-saving potential than those mounted in the east and west for all climatic regions. The conclusions of this study provide a theoretical basis for PV shading systems’ design and installation.

Estimation of solar radiation and optimum tilt angles for south-facing surfaces in Humid Subtropical Climatic Region of India

In the present work, availability of solar radiation for south-facing flat surfaces in Humid Subtropical Climatic Region of India has been estimated. Measurements of global and diffuse solar radiation for Aligarh (27.89°N, 78.08°E) which lies in the Humid Subtropical Climatic Region were performed for over a period of three years. Monthly, seasonal and annual optimum tilt angles were estimated. Comparison of total incident solar radiation was performed between Aligarh and New Delhi (Capital of India, 28.61°N, 77.20°E). Annual optimum tilt angle for Aligarh and New Delhi was found as 27.62° and 27.95° respectively (close to the latitude of the respective location). Estimated gains in annual average solar radiation (based on monthly, seasonal and annual optimum tilt angles) in comparison to a horizontal surface were 12.92%, 11.61% and 6.51% (for Aligarh) and 13.13%, 11.80% and 7.58% (for New Delhi) respectively. A loss of 1.16% and 5.68% energy (for Aligarh) and 1.18% and 4.91% (for New Delhi) were estimated with surface at seasonal and annual optimum tilt angles respectively compared to a surface at monthly optimum tilt angle. Based on the study, it was recommended that the inclined surface must be tilted on monthly or seasonal optimum tilt angle for better utilization of solar energy.

Determination of Solar Collector Optimum Tilt Angle for Ankara and Districts

This study that is Ankara province and districts based deals with the determination of the optimum tilt angle to maximize the performances of solar collector and solar panel. In Ankara, fixed solar collectors are usually placed at slope of 40°. In this study, annual optimum tilt angle for Ankara province and districts was calculated as 34°±1 however the optimum angles during the year were calculated between 1° and 67°. The results of this study are compared with similar studies in the literature they were found to be consistent with the results of similar studies. Also, the tilt angle was calculated for the six months periods as 15° and 56°, for seasonal periods (winter, spring, summer, autumn) as 62°, 23°, 6° and 49°, respectively and solar radiation for optimum angles of inclination were found. When the tilt angle is changed only twice a year, due to increasing the amount of energy per unit area, according to the annual tilt angle fixed product they provides energy efficiency by about 5%. On the other hand, when the tilt angle is changed every month this ratio can be reached approximately 8%. For increasing the utilization efficiency of solar collectors and panels, it is recommended adjusting of the tilt angle once a month or at least twice a year.

Analysis of fixed tilt and sun tracking photovoltaic–micro wind based hybrid power systems

In this study fixed tilt and sun tracking photovoltaic based micro wind hybrid power systems are analyzed along with determining the optimum configurations for a 6kWp roof mounted micro wind based hybrid system using fixed and tracking photovoltaic systems to enhance the power generation potential in a low windy Indian hilly terrain with good solar resource. The main objective of the study is to enhance power generation by focusing on photovoltaic component of the hybrid system. A comparative power generation analysis of different configurations of hybrid systems with fixed tilt, monthly optimum tilt, yearly optimum tilt and 6 different sun tracking photovoltaic systems is carried out using Hybrid Optimization Model for Electric Renewables. Monthly and seasonal optimum tilt angles determined for the location vary between 0° and 60° with annual optimum tilt angle as 29.25°. The optimum configurations for all sun tracking systems except for the two axis tracking system is found to be 7kWp photovoltaic system, one 5kWp wind turbine, 10 batteries and a 2kWp inverter. The optimum configuration for two axis tracking system and two types of fixed tilt systems, is found to be a 8kWp photovoltaic system, one 5kWp wind turbine, 10 batteries and a 2kWp inverter. The results show that horizontal axis with monthly adjustment, horizontal axis with daily adjustment, horizontal axis with continuous adjustment and two axis tracking system generate 4.88–26.29% more energy per year than the existing fixed tilt photovoltaic system. The cost of energy is found to be more for two axis tracking than all tracking systems and fixed tilted photovoltaic system. However, two axis tracking is found to be more advantageous than other systems despite higher costs to maximize power output of the hybrid systems. The methodology followed can be applied to improve the power generation potential of photovoltaic–micro wind based hybrid systems for any location worldwide.

Verification of computational optimum tilt angles of a photovoltaic module using an experimental photovoltaic system

Determination of the optimum tilt angles of a photovoltaic module is of great importance because the power of photovoltaic module is highly dependent on the incident solar radiation. The purpose of this research was to verify the computational optimum tilt angles of a PV module by conducting an experimental research in Kerman‐Iran. For achieving this, first, the optimum tilt angles were found using a computational model which predicts the module output energy at different tilt angles. Second, monthly, seasonal, biannual, and annual optimum tilt angles of a photovoltaic module were measured. The experimental optimum tilt angles were obtained based on 1 year measured data of the output energies of photovoltaic modules. The experiments were carried out by measuring the output electrical power of six photovoltaic modules which were inclined toward the south at different tilt angles throughout the year. The experimental optimum tilt angles were then determined based on the maximum output energy of the PV modules. Finally, the computational optimum tilt angle and the experimental optimum tilt angle were compared with each other. The results showed differences between the calculated and the measured optimum tilt angles of a PV module in the region under investigation. It was revealed that the measured annual optimum tilt angle is higher than the calculated annual optimum tilt angle. This difference was due to lack of the environmental parameter influences such as dust deposition on the PV front surface in the computational model. This study clearly showed that fixing the photovoltaic module based on the calculated annual optimum tilt angles decreases 3% the electrical output energy of photovoltaic module throughout the year compared with that fixed at the experimental optimum tilt angle. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 1156–1165, 2015

مقارنة بين زوايا الميل للألواح الشمسية الثابتة لمدينة بغداد باستخدام جهاز محلل الظل للإشعاع الشمسي على مدار سنة كاملة

Generated energy by fixed solar panels depended on the optimum tilt angle with the horizon, so it must be defined correctly to improve the performance of the solar panel system. In this research the values of optimum tilt angle with the horizon of solar panels for Baghdad city was calculated monthly and quarterly and annually by using shadow analyzer of solar radiation. The optimum tilt angles is (60.51, 37, 19.5, 0, 0.13, 30, 45.55 , 60) degrees monthly, respectively and quarterly is 58 ° for months (12, 1, 2) and 19 degrees for months (3, 4, 5) and 2 degrees for months (6, 7, 8) and 45 degrees for months (9, 10, 11 ) When dividing the year into two seasons the optimal angle is 13 degrees for months (4, 5, 6, 7, 8, 9) and 51 degrees for months (10,11, 12, 1, 2, 3). The annual optimum tilt angle is 30 degrees it is noticed an increase in optimum tilt angle in winter than in summer and that is because of the increasing in the sun declination and the decreasing in the number of noon hours in winter. The increasing in the amount of energy falling on the solar panels was 8.34% when the tilt angle changed monthly and 6.85% when it changed quarterly and 6.61% when it changed for two seasons with respect to yearly fix tilt angle.

Analytical investigation of collector optimum tilt angle at low latitude

An analytical investigation on the optimum tilt angle for solar collectors at low latitude, a case study of Universiti Teknologi PETRONAS (UTP), 4.39°N and 100.98°E, Malaysia is presented in this work. The study employed Hay, Davies, Klucher, and Reindl (HDKR) anisotropic sky model to evaluate the available hourly solar radiation on inclined surface using the location metrological data. The tilt angles considered were 0° to 30° in step of 3° with the inclusion of the location latitude angle. The study employed the ratio of global solar radiation on tilted surface to the global solar radiation on horizontal surface in the decision of the optimum tilt. The system equations were converted to MATLAB codes to solve for the optimum tilt angles. The results show that the optimum tilt varies monthly but gave zero degree for south facing collector for the months of April to August; thus, the investigation also considered north facing orientation for the months of April to September. The optimum annual tilt angle for the location using the tilt to horizontal radiation ratio was found to be equal to the location latitude angle. Using the conventional average of the monthly optimum tilt angles, the annual optimum tilt angle was found to be 9.75° for south facing collector. Considering seasonal optimum tilt angle for the location using the tilt to horizontal radiation ratio, 18° facing south was found to be the optimum tilt angle for rainy season (September to March) and 15° facing north for dry season (April to August). Employing the average of monthly optimum tilt method, the seasonal optimum tilt angle was found to be 17° for rainy season and 12° facing north dry season. The effect of dust on the collector was considered with reference to literature and the annual tilt angle of 15° facing south was recommended for the location in the case of large solar collector that cannot be monthly or seasonally adjusted.

Study of optimum tilt angles for solar panels in different latitudes for urban applications

Solar panels are one of the most promising renewable technologies for energizing future buildings. For roof top solar panel installations, knowledge of the optimum tilt angle is important to have the maximum annual or seasonal energy yield. The annual optimum tilt angle is dependent on many factors such as the latitude of the location and the weather condition. In an urban application, the optimum tilt angle can be affected by the surrounding obstacles. Consequently, new concerns such as shading or sky blocking effects have to be taken into consideration. In this paper, a simple method is proposed based on a modified sky model to calculate the optimum angle of installation for the urban applications. The obtained results demonstrate the dependency of the optimum angle of installation on the latitude, weather condition and surroundings.

Optimization of tilt angle for solar panel: Case study for Madinah, Saudi Arabia

This article analyzes the optimal choice of the tilt angle for the solar panel in order to collect the maximum solar irradiation. In this paper, the collector surface is assumed to be facing toward equator. The study is based upon the measured values of daily global and diffuse solar radiation on a horizontal surface. It is shown that the optimal angle of tilt ( β opt ) for each month, allows us to collected the maximum solar energy for Madinah site. Annual optimum tilt angle is found to be approximately equal to latitude of the location. It is found that the loss in the amount of collected energy when using the yearly average fixed angle is around 8% compared with the monthly optimum tilt β opt .

Optimization of solar flat collector inclination

Solar collectors need to be inclined at the optimum angle to maximize the receiving energy. In spite of many theoretical and experimental investigations on optimization of solar collector inclination, there is an inconsistency in presented results. In this paper, solar global radiation on a horizontal surface was estimated using a mathematical model and the results were compared with the recorded data from the Zahedan city meteorological station. Total received solar energy by a flat inclined collector was determined in a certain day, and searching for the angle which has the maximum incident energy was the general procedure in determination of daily optimum tilt angle. In case of operational limitation for daily tilt adjustment, this procedure is repeated for other specific period of time and monthly, seasonal, semi-annual and annual optimum tilt angles were determined. A MATLAB-based code is used to calculate the daily optimum tilt angle. The results were in good agreement with the obtained data of a new constructed device. Finally, in the case of stationary devices, some recommendations were presented with respect to their typical application.

Optimization of Tilt Angle for Solar Collector to Receive Maximum Radiation

This article examines the theoretical aspects of choosing a tilt angle for the solar flat-plate collectors used at ten different stations in the world and makes recommendations on how the collected energy can be increased by varying the tilt angle. In this paper, the collector surface is assumed to be facing toward equator. For Indian stations, the calculations are based upon the measured values of monthly mean daily global and diffuse solar radiation on a horizontal surface. For other stations, the calculations are based upon the data of monthly mean daily global solar radiation and monthly average clearness index on a horizontal surface. It is shown that nearly optimal energy can be collected if the angle of tilt is varied seasonally, four times a year. Annual optimum tilt angle is found to be approximately equal to latitude of the location. It is found that the loss in the amount of collected energy is around 1 % if the angle of tilt is adjusted seasonally instead of us- ing  opt for each month of the year. The loss of energy when using the yearly average fixed angle is around 15 % com- pared with the monthly optimum tilt.

Investigation and Economic Analysis of the Optimum Tilt Angle of Solar Panels for Three Cities in Azerbaijan

Abstract— Interest in photovoltaic solar panels, a renewable energy source, is increasing day by day, and the installation of solar panels is becoming more widespread. To achieve maximum efficiency from solar panels, they must be installed at a specific angle. In this study, a Photovoltaic Geographical Information System (PVGIS), capable of performing calculations based on latitude, longitude data, and satellite data, was used to determine the optimum tilt angle for three selected regions in Azerbaijan. The optimum tilt angles were determined for monthly, seasonal, and annual periods for the selected regions, and the global irradiation and maximum energy production values at these angles were compared. In practical applications, the tilt angle is set equal to the latitude. The energy production at the monthly, seasonal, and annual optimum tilt angles was compared with the practical application. When the tilt angle is determined annually, the gain is 0.66%, while the gain increases to 4.2% when the angle is set seasonally. When the tilt angle is adjusted monthly, the gain reaches 4.91%, achieving the highest gain. The gain increases and the efficiency of the installed panels improves when the tilt angle is determined monthly and seasonally.

Present status and future of the solar stills : Nebbia, Giorgio United Nations Conference on New Sources of Energy, Rome, 1961, 12. p., Illus.

In the present work, availability of solar radiation for south-facing flat surfaces in Humid Subtropical Climatic Region of India has been estimated. Measurements of global and diffuse solar radiation for Aligarh (27.89°N, 78.08°E) which lies in the Humid Subtropical Climatic Region were performed for over a period of three years. Monthly, seasonal and annual optimum tilt angles were estimated. Comparison of total incident solar radiation was performed between Aligarh and New Delhi (Capital of India, 28.61°N, 77.20°E). Annual optimum tilt angle for Aligarh and New Delhi was found as 27.62° and 27.95° respectively (close to the latitude of the respective location). Estimated gains in annual average solar radiation (based on monthly, seasonal and annual optimum tilt angles) in comparison to a horizontal surface were 12.92%, 11.61% and 6.51% (for Aligarh) and 13.13%, 11.80% and 7.58% (for New Delhi) respectively. A loss of 1.16% and 5.68% energy (for Aligarh) and 1.18% and 4.91% (for New Delhi) were estimated with surface at seasonal and annual optimum tilt angles respectively compared to a surface at monthly optimum tilt angle. Based on the study, it was recommended that the inclined surface must be tilted on monthly or seasonal optimum tilt angle for better utilization of solar energy.