The document discusses the appraisal of solar resources. It covers topics such as solar radiation characteristics, the classical evaluation of solar radiation, the interaction of solar radiation with the atmosphere, and the study of direct solar radiation. The document provides information on measuring and estimating solar radiation data from satellites and numerical weather prediction models. It also discusses generating time series for simulation and databases of solar radiation data available online.
Hello, I am Subhajit Pramanick. I and my classmate, Shivani Gupta, both presented this ppt in seminar of our university, Banaras Hindu University. Here it is the experiment how to determine Synodic and Sidereal time period of rotation of the Sun by tracing Sun spots. This presentation consists both the theory as well as experiment part. We hope you will all enjoy by reading this presentation. Thank you.
The document presents information on solar radiations and geometry. It discusses that the sun generates enormous energy and provides the earth with around 1500 quadrillion kilowatt-hours per year. However, only around 47% of the sun's energy reaches the earth's surface due to reflection and absorption in the atmosphere. It then outlines several important angles used in solar radiation analysis, including latitude, declination, hour angle, altitude angle, zenith angle, solar azimuth angle, and slope.
The document defines sunshine as direct sunlight of at least 120 w/m2 measured on the ground. It provides details on the sun's composition and radiation, including that 53.12% of its energy is in the infrared region. It also discusses how the Earth reflects 1/3 of sunlight and is inclined at 23.5 degrees on its axis. Finally, it describes various instruments used to measure solar radiation, including pyranometers and pyrheliometers, and concepts like beam radiation, diffuse radiation, and solar declination.
1) The Earth orbits the sun once every 365 days and its axis is tilted at an angle of 23.5 degrees. This tilt and rotation cause the seasons by changing the amount of direct sunlight different parts of the Earth receive over the course of a year.
2) The maximum tilt toward the sun occurs on June 21st in the Northern Hemisphere and December 21st in the Southern Hemisphere, corresponding to the summer and winter solstices.
3) On the equinoxes in March and September, both hemispheres receive equal amounts of sunlight and day and night are equal lengths.
Gyroscope sensors measure angular velocity by detecting the Coriolis effect on a vibrating mass. They have specifications including measurement range, number of sensing axes, nonlinearity, temperature range, and noise parameters. MEMS gyroscopes typically use a vibrating proof mass driven electrostatically while rotation is detected via sense electrodes measuring the Coriolis-induced deflection perpendicular to the drive mode. The Coriolis effect causes an apparent deflection in a rotating reference frame due to inertial forces.
This document summarizes the structure and magnetic properties of the Sun. It describes the core, radiative zone, and convective zone in the Sun's interior. It also discusses the photosphere, chromosphere, corona, and heliosphere that make up the Sun's atmosphere. The document then focuses on the Sun's magnetic field and how sunspots and solar activity vary in a approximately 11-year cycle. It introduces the alpha-omega dynamo model to explain how differential rotation and plasma currents generate and maintain the Sun's magnetic field through self-exciting dynamo action.
Tis ppt gives u a brief glance on the following topics:
Escape Speed
Earth Satellites
Geostationary And Polar Satellites
Weightlessness
If u want to download the ppt mail me to raviteja711@gmail.com
Instruments for solar radiation measurement
Empirical equation for prediction of availability of solar radiation
Radiation on tilted surface
Types of solar collectors
kushsshah.blogspot.com
Hello, I am Subhajit Pramanick. I and my classmate, Shivani Gupta, both presented this ppt in seminar of our university, Banaras Hindu University. Here it is the experiment how to determine Synodic and Sidereal time period of rotation of the Sun by tracing Sun spots. This presentation consists both the theory as well as experiment part. We hope you will all enjoy by reading this presentation. Thank you.
The document presents information on solar radiations and geometry. It discusses that the sun generates enormous energy and provides the earth with around 1500 quadrillion kilowatt-hours per year. However, only around 47% of the sun's energy reaches the earth's surface due to reflection and absorption in the atmosphere. It then outlines several important angles used in solar radiation analysis, including latitude, declination, hour angle, altitude angle, zenith angle, solar azimuth angle, and slope.
The document defines sunshine as direct sunlight of at least 120 w/m2 measured on the ground. It provides details on the sun's composition and radiation, including that 53.12% of its energy is in the infrared region. It also discusses how the Earth reflects 1/3 of sunlight and is inclined at 23.5 degrees on its axis. Finally, it describes various instruments used to measure solar radiation, including pyranometers and pyrheliometers, and concepts like beam radiation, diffuse radiation, and solar declination.
1) The Earth orbits the sun once every 365 days and its axis is tilted at an angle of 23.5 degrees. This tilt and rotation cause the seasons by changing the amount of direct sunlight different parts of the Earth receive over the course of a year.
2) The maximum tilt toward the sun occurs on June 21st in the Northern Hemisphere and December 21st in the Southern Hemisphere, corresponding to the summer and winter solstices.
3) On the equinoxes in March and September, both hemispheres receive equal amounts of sunlight and day and night are equal lengths.
Gyroscope sensors measure angular velocity by detecting the Coriolis effect on a vibrating mass. They have specifications including measurement range, number of sensing axes, nonlinearity, temperature range, and noise parameters. MEMS gyroscopes typically use a vibrating proof mass driven electrostatically while rotation is detected via sense electrodes measuring the Coriolis-induced deflection perpendicular to the drive mode. The Coriolis effect causes an apparent deflection in a rotating reference frame due to inertial forces.
This document summarizes the structure and magnetic properties of the Sun. It describes the core, radiative zone, and convective zone in the Sun's interior. It also discusses the photosphere, chromosphere, corona, and heliosphere that make up the Sun's atmosphere. The document then focuses on the Sun's magnetic field and how sunspots and solar activity vary in a approximately 11-year cycle. It introduces the alpha-omega dynamo model to explain how differential rotation and plasma currents generate and maintain the Sun's magnetic field through self-exciting dynamo action.
Tis ppt gives u a brief glance on the following topics:
Escape Speed
Earth Satellites
Geostationary And Polar Satellites
Weightlessness
If u want to download the ppt mail me to raviteja711@gmail.com
Instruments for solar radiation measurement
Empirical equation for prediction of availability of solar radiation
Radiation on tilted surface
Types of solar collectors
kushsshah.blogspot.com
This document provides information about calculating solar radiation. It begins by defining key terms like solar constant, latitude, longitude, declination, and hour angle that are used to determine the position of the sun. It then describes how to calculate the extraterrestrial radiation, zenith angle, sun altitude, solar azimuth, and incidence angle on sloped surfaces. Equations are provided to calculate daily and hourly extraterrestrial radiation. The document also discusses how the atmosphere influences solar radiation, noting that 53% of solar radiation reaches the earth's surface, with 31% as direct beam radiation and 22% as diffuse radiation.
This document presents a mathematical model for estimating solar radiation incident on a horizontal surface. It begins with background on solar radiation and the sun-earth relationship. It then describes collecting solar radiation data for Dhaka, Bangladesh and using the Angstrom-Prescott method to evaluate regression coefficients a and b. The regression model determined is H/H0 = 0.11 + 0.70(n/N). This model is then used to estimate monthly solar radiation and is compared to other models, showing the lowest percentage mean bias error and root mean square error.
This document defines and describes the major types of orbits used for satellites, including:
Low Earth orbit (LEO), polar orbits, and sun-synchronous orbits which are below 225 minutes in period. Geostationary orbit is a special case of geosynchronous orbit with zero inclination and eccentricity. Geosynchronous orbit matches Earth's sidereal day but can have inclination and eccentricity. Mid-Earth orbit is also called semi-synchronous. High-Earth orbit is above geosynchronous. Transfer orbits are used to change between orbit types and geosynchronous transfer orbit is used specifically for geosynchronous orbit.
This document discusses spacecraft attitude dynamics and control. It begins by introducing typical modes of spacecraft operation like attitude acquisition and nominal earth pointing. It then covers key topics like reference frames, attitude representation using Euler angles, quaternions and direction cosine matrices, orbital elements, external disturbances, and spacecraft attitude dynamics equations. Quaternion algebra is described for representing attitude and performing successive rotations between frames. Overall, the document provides an overview of fundamental concepts for analyzing and controlling a spacecraft's orientation in space.
1. Magnetic compasses indicate magnetic north using the Earth's magnetic field, while gyro compasses indicate true north by measuring the Earth's rotation and are unaffected by magnetic fields.
2. A gyroscope maintains its orientation in space regardless of movement by relying on the principle of gyroscopic inertia. It has three degrees of freedom and its orientation remains fixed due to precession caused by external torques.
3. Errors in gyrocompasses like speed error and ballistic deflection error occur due to the Earth's rotation and changes in a ship's speed or course, but can be compensated for through electrical adjustments and a dual rotor design.
The document discusses three common methods for measuring solar radiation: pyranometers, pyrheliometers, and sunshine recorders. Pyranometers measure total solar radiation on a plane surface and contain an inner absorbing disk and outer dome, as well as a thermopile temperature sensor to compare the temperature rise between the disks. Pyrheliometers specifically measure direct solar irradiance and have a thermopile sensor and glass dome that tracks the sun. Sunshine recorders use a sensor to record the time period when sunlight is strong enough that a threshold is exceeded.
A gyroscope is a device that uses angular momentum to detect orientation and maintain stability. It works based on the principle that a torque applied perpendicular to the gyroscope's axis of rotation causes it to precess around an axis perpendicular to both the torque and its angular momentum. Modern gyroscopes use electronics and include microelectromechanical systems, fiber optic gyroscopes, vibrating structure gyroscopes, dynamically tuned gyroscopes, and laser-based gyroscopes.
EARTH QUACK AND ITS TYPES BRIEFLY EXPLAINHafiz JUNAID
Tectonic earthquakes are the most common type and are caused by rocks breaking in response to geological forces. Other earthquake types include volcanic, collapse, and human-caused explosions. Early seismographs used pendulums to record ground motions, while modern ones use electronics. Seismic waves include P and S body waves and surface Love and Rayleigh waves. Locating earthquakes requires analyzing arrival times at multiple seismograph stations. The development of seismology helped establish that earthquakes are caused by fault ruptures rather than effects.
1) A marine gyrocompass uses a freely-spinning gyroscope to determine direction based on the principles of angular momentum and the earth's constant rotation.
2) A gyroscope has three degrees of freedom - it can spin about its axis and tilt or turn in horizontal and vertical planes. The earth acts like a giant free gyroscope due to its mass, high-speed rotation, and lack of friction in space.
3) The gyroscope's angular momentum and inertia cause it to resist changes to its axis of spin, allowing it to maintain a fixed direction in space independent of the ship's movements. This gyroscopic property is used to determine true north.
The document discusses solar irradiance measurement and terminology. It defines key terms like global horizontal irradiance (GHI), direct normal irradiance (DNI), and diffuse horizontal irradiance (DHI). It explains how irradiance and the spectrum of sunlight vary over the course of a day and year due to the sun's changing position in the sky. Examples of measuring these variables and relating GHI, DNI, and DHI are provided. Applications like solar panel power production and educational solar lab kits are also mentioned.
This document presents equations to compute the efficiency of a parabolic-trough solar collector using solar position coordinates. The equations account for factors like universal time, day, month, year, longitude, latitude, and heliocentric and geocentric coordinates to determine the sun's position. The collector efficiency considers the direct and reflected solar energy incident on its glass cover as well as thermal losses. The developed equations can predict collector performance using meteorological and radiative data for any location.
The document discusses solar radiation and presents a mathematical model for predicting global solar radiation on a horizontal surface. It describes how solar radiation reaches Earth from the sun and the amount of energy received. The model calculates hourly, daily, and monthly global radiation based on factors like Julian date, cloudiness, and sun position. Validation shows the model estimates daily radiation within 4.5% accuracy and monthly radiation within 0.34% compared to experimental data.
This document discusses different types of satellite orbits. It defines an orbit as two bodies orbiting a common center of mass. It describes Kepler's laws of planetary motion. It then defines and compares different orbit classifications including altitude classifications like geostationary and low Earth orbits, inclination classifications, eccentricity classifications, and others. It provides details on important orbit types like geostationary, low Earth, and medium Earth orbits.
The document summarizes the design of a 1 kW solar photovoltaic system for a college in Andhra Pradesh, India. It discusses the geographical and meteorological factors considered for setup, including latitude, longitude, radiation data, and temperature. It also outlines the key components of the system, such as solar panels, mounting structures, cables, and inverter. Mathematical equations are presented for estimating energy output based on location parameters. A single-axis solar tracker is proposed to improve energy capture and its design requirements are analyzed.
The document discusses Earth's magnetic field, which is generated in the liquid outer core by electrical currents. It can be observed to vary in space and time due to processes within Earth and from the Sun. Observations are made at geomagnetic observatories, through surveys on land and from aircraft/satellites, and by studying rocks' magnetic properties. The field can both aid navigation/drilling and interfere with satellite operations.
Mechanics of Machines (Gyroscopes) as per MGU syllabusbinil babu
1. The document discusses the gyroscopic effect, which is the tendency of a spinning object to resist any change to its axis of rotation. It explains how a gyroscopic couple is generated when a spinning object experiences precession.
2. Key applications of gyroscopic effect discussed include aeroplanes, ships, vehicles. For aeroplanes, the effect of the spinning engine/propeller is to change the plane's attitude during turns. For ships steering or pitching, it causes the bow/stern to raise or lower. There is no effect during ship rolling.
3. Sample calculations are provided to determine the gyroscopic couple generated for different rotating objects like engines, flywheels, and to analyze their effect
This document discusses seismic surveying methods used in geophysical exploration. It describes how seismic waves are generated artificially and recorded to map subsurface structures and lithologies. The main methods discussed are 2D and 3D seismic surveys. 2D surveys involve collecting seismic data along widely spaced lines, while 3D surveys acquire closely-spaced data to generate high-resolution 3D images of the subsurface. The document outlines the objectives, preparation, data acquisition, and interpretation of seismic data to infer the presence of oil and gas reservoirs.
The document summarizes a simulation of controlling an Earth observing satellite. A set of reaction wheels were used to align the spacecraft with the Local Vertical Local Horizontal frame and deploy the solar panels and sensor. The spacecraft then targeted 7 points on Earth's surface over one orbit, applying control torques to account for disturbance torques. A Monte Carlo simulation estimated total pointing error of 0.109 degrees. The mission was successful in controlling the spacecraft and pointing the sensor at desired locations.
Adaptive optics are used in ground-based telescopes to directly image extrasolar planets and overcome atmospheric turbulence. Atmospheric turbulence causes distortions that blur planetary images. Adaptive optics systems measure wavefront distortions using a wavefront sensor and correct for them using a deformable mirror in a closed-loop system. This results in sharper, diffraction-limited images that help verify exoplanets. Future extremely large telescopes will use many more actuators on deformable mirrors to provide substantial correction, aiding the search for Earth-like exoplanets.
Solar energy can be harnessed using a range of technologies to capture and convert sunlight into useful forms of energy. There are two main types of solar energy technologies - passive solar, which uses sunlight without active solar components, and active solar, which uses electro-mechanical devices to convert sunlight into electricity or to power machinery. Solar energy can be used for heating, cooling, power generation, and other applications by using technologies like solar thermal collectors and photovoltaic panels. The amount of solar energy reaching the Earth's surface depends on geographic factors like latitude and weather conditions.
Lecture Slides - Solar Energy Basics and Utilization (1).pdfGian Jyoti Group
This document discusses solar energy basics including solar radiation, solar resource assessment, and solar geometry. Some key points:
- Solar radiation received on Earth consists of direct beam and diffuse radiation after passing through the atmosphere. The amount of each component depends on factors like air mass and atmospheric conditions.
- Solar geometry concepts like zenith angle, declination, and hour angle are used to determine the direction of incoming solar radiation and calculate quantities like duration of sunshine.
- Equations are provided to calculate the angle of incidence of direct radiation on tilted surfaces, as well as the total solar radiation received, accounting for direct beam, diffuse sky, and ground-reflected components.
This document provides information about calculating solar radiation. It begins by defining key terms like solar constant, latitude, longitude, declination, and hour angle that are used to determine the position of the sun. It then describes how to calculate the extraterrestrial radiation, zenith angle, sun altitude, solar azimuth, and incidence angle on sloped surfaces. Equations are provided to calculate daily and hourly extraterrestrial radiation. The document also discusses how the atmosphere influences solar radiation, noting that 53% of solar radiation reaches the earth's surface, with 31% as direct beam radiation and 22% as diffuse radiation.
This document presents a mathematical model for estimating solar radiation incident on a horizontal surface. It begins with background on solar radiation and the sun-earth relationship. It then describes collecting solar radiation data for Dhaka, Bangladesh and using the Angstrom-Prescott method to evaluate regression coefficients a and b. The regression model determined is H/H0 = 0.11 + 0.70(n/N). This model is then used to estimate monthly solar radiation and is compared to other models, showing the lowest percentage mean bias error and root mean square error.
This document defines and describes the major types of orbits used for satellites, including:
Low Earth orbit (LEO), polar orbits, and sun-synchronous orbits which are below 225 minutes in period. Geostationary orbit is a special case of geosynchronous orbit with zero inclination and eccentricity. Geosynchronous orbit matches Earth's sidereal day but can have inclination and eccentricity. Mid-Earth orbit is also called semi-synchronous. High-Earth orbit is above geosynchronous. Transfer orbits are used to change between orbit types and geosynchronous transfer orbit is used specifically for geosynchronous orbit.
This document discusses spacecraft attitude dynamics and control. It begins by introducing typical modes of spacecraft operation like attitude acquisition and nominal earth pointing. It then covers key topics like reference frames, attitude representation using Euler angles, quaternions and direction cosine matrices, orbital elements, external disturbances, and spacecraft attitude dynamics equations. Quaternion algebra is described for representing attitude and performing successive rotations between frames. Overall, the document provides an overview of fundamental concepts for analyzing and controlling a spacecraft's orientation in space.
1. Magnetic compasses indicate magnetic north using the Earth's magnetic field, while gyro compasses indicate true north by measuring the Earth's rotation and are unaffected by magnetic fields.
2. A gyroscope maintains its orientation in space regardless of movement by relying on the principle of gyroscopic inertia. It has three degrees of freedom and its orientation remains fixed due to precession caused by external torques.
3. Errors in gyrocompasses like speed error and ballistic deflection error occur due to the Earth's rotation and changes in a ship's speed or course, but can be compensated for through electrical adjustments and a dual rotor design.
The document discusses three common methods for measuring solar radiation: pyranometers, pyrheliometers, and sunshine recorders. Pyranometers measure total solar radiation on a plane surface and contain an inner absorbing disk and outer dome, as well as a thermopile temperature sensor to compare the temperature rise between the disks. Pyrheliometers specifically measure direct solar irradiance and have a thermopile sensor and glass dome that tracks the sun. Sunshine recorders use a sensor to record the time period when sunlight is strong enough that a threshold is exceeded.
A gyroscope is a device that uses angular momentum to detect orientation and maintain stability. It works based on the principle that a torque applied perpendicular to the gyroscope's axis of rotation causes it to precess around an axis perpendicular to both the torque and its angular momentum. Modern gyroscopes use electronics and include microelectromechanical systems, fiber optic gyroscopes, vibrating structure gyroscopes, dynamically tuned gyroscopes, and laser-based gyroscopes.
EARTH QUACK AND ITS TYPES BRIEFLY EXPLAINHafiz JUNAID
Tectonic earthquakes are the most common type and are caused by rocks breaking in response to geological forces. Other earthquake types include volcanic, collapse, and human-caused explosions. Early seismographs used pendulums to record ground motions, while modern ones use electronics. Seismic waves include P and S body waves and surface Love and Rayleigh waves. Locating earthquakes requires analyzing arrival times at multiple seismograph stations. The development of seismology helped establish that earthquakes are caused by fault ruptures rather than effects.
1) A marine gyrocompass uses a freely-spinning gyroscope to determine direction based on the principles of angular momentum and the earth's constant rotation.
2) A gyroscope has three degrees of freedom - it can spin about its axis and tilt or turn in horizontal and vertical planes. The earth acts like a giant free gyroscope due to its mass, high-speed rotation, and lack of friction in space.
3) The gyroscope's angular momentum and inertia cause it to resist changes to its axis of spin, allowing it to maintain a fixed direction in space independent of the ship's movements. This gyroscopic property is used to determine true north.
The document discusses solar irradiance measurement and terminology. It defines key terms like global horizontal irradiance (GHI), direct normal irradiance (DNI), and diffuse horizontal irradiance (DHI). It explains how irradiance and the spectrum of sunlight vary over the course of a day and year due to the sun's changing position in the sky. Examples of measuring these variables and relating GHI, DNI, and DHI are provided. Applications like solar panel power production and educational solar lab kits are also mentioned.
This document presents equations to compute the efficiency of a parabolic-trough solar collector using solar position coordinates. The equations account for factors like universal time, day, month, year, longitude, latitude, and heliocentric and geocentric coordinates to determine the sun's position. The collector efficiency considers the direct and reflected solar energy incident on its glass cover as well as thermal losses. The developed equations can predict collector performance using meteorological and radiative data for any location.
The document discusses solar radiation and presents a mathematical model for predicting global solar radiation on a horizontal surface. It describes how solar radiation reaches Earth from the sun and the amount of energy received. The model calculates hourly, daily, and monthly global radiation based on factors like Julian date, cloudiness, and sun position. Validation shows the model estimates daily radiation within 4.5% accuracy and monthly radiation within 0.34% compared to experimental data.
This document discusses different types of satellite orbits. It defines an orbit as two bodies orbiting a common center of mass. It describes Kepler's laws of planetary motion. It then defines and compares different orbit classifications including altitude classifications like geostationary and low Earth orbits, inclination classifications, eccentricity classifications, and others. It provides details on important orbit types like geostationary, low Earth, and medium Earth orbits.
The document summarizes the design of a 1 kW solar photovoltaic system for a college in Andhra Pradesh, India. It discusses the geographical and meteorological factors considered for setup, including latitude, longitude, radiation data, and temperature. It also outlines the key components of the system, such as solar panels, mounting structures, cables, and inverter. Mathematical equations are presented for estimating energy output based on location parameters. A single-axis solar tracker is proposed to improve energy capture and its design requirements are analyzed.
The document discusses Earth's magnetic field, which is generated in the liquid outer core by electrical currents. It can be observed to vary in space and time due to processes within Earth and from the Sun. Observations are made at geomagnetic observatories, through surveys on land and from aircraft/satellites, and by studying rocks' magnetic properties. The field can both aid navigation/drilling and interfere with satellite operations.
Mechanics of Machines (Gyroscopes) as per MGU syllabusbinil babu
1. The document discusses the gyroscopic effect, which is the tendency of a spinning object to resist any change to its axis of rotation. It explains how a gyroscopic couple is generated when a spinning object experiences precession.
2. Key applications of gyroscopic effect discussed include aeroplanes, ships, vehicles. For aeroplanes, the effect of the spinning engine/propeller is to change the plane's attitude during turns. For ships steering or pitching, it causes the bow/stern to raise or lower. There is no effect during ship rolling.
3. Sample calculations are provided to determine the gyroscopic couple generated for different rotating objects like engines, flywheels, and to analyze their effect
This document discusses seismic surveying methods used in geophysical exploration. It describes how seismic waves are generated artificially and recorded to map subsurface structures and lithologies. The main methods discussed are 2D and 3D seismic surveys. 2D surveys involve collecting seismic data along widely spaced lines, while 3D surveys acquire closely-spaced data to generate high-resolution 3D images of the subsurface. The document outlines the objectives, preparation, data acquisition, and interpretation of seismic data to infer the presence of oil and gas reservoirs.
The document summarizes a simulation of controlling an Earth observing satellite. A set of reaction wheels were used to align the spacecraft with the Local Vertical Local Horizontal frame and deploy the solar panels and sensor. The spacecraft then targeted 7 points on Earth's surface over one orbit, applying control torques to account for disturbance torques. A Monte Carlo simulation estimated total pointing error of 0.109 degrees. The mission was successful in controlling the spacecraft and pointing the sensor at desired locations.
Adaptive optics are used in ground-based telescopes to directly image extrasolar planets and overcome atmospheric turbulence. Atmospheric turbulence causes distortions that blur planetary images. Adaptive optics systems measure wavefront distortions using a wavefront sensor and correct for them using a deformable mirror in a closed-loop system. This results in sharper, diffraction-limited images that help verify exoplanets. Future extremely large telescopes will use many more actuators on deformable mirrors to provide substantial correction, aiding the search for Earth-like exoplanets.
Solar energy can be harnessed using a range of technologies to capture and convert sunlight into useful forms of energy. There are two main types of solar energy technologies - passive solar, which uses sunlight without active solar components, and active solar, which uses electro-mechanical devices to convert sunlight into electricity or to power machinery. Solar energy can be used for heating, cooling, power generation, and other applications by using technologies like solar thermal collectors and photovoltaic panels. The amount of solar energy reaching the Earth's surface depends on geographic factors like latitude and weather conditions.
Lecture Slides - Solar Energy Basics and Utilization (1).pdfGian Jyoti Group
This document discusses solar energy basics including solar radiation, solar resource assessment, and solar geometry. Some key points:
- Solar radiation received on Earth consists of direct beam and diffuse radiation after passing through the atmosphere. The amount of each component depends on factors like air mass and atmospheric conditions.
- Solar geometry concepts like zenith angle, declination, and hour angle are used to determine the direction of incoming solar radiation and calculate quantities like duration of sunshine.
- Equations are provided to calculate the angle of incidence of direct radiation on tilted surfaces, as well as the total solar radiation received, accounting for direct beam, diffuse sky, and ground-reflected components.
This document provides an overview of solar energy and solar radiation concepts. It discusses topics like solar radiation geometry, measurement of solar radiation, extraterrestrial and terrestrial radiation, scattering and absorption in the atmosphere, air mass, and formulas for calculating the angle of incidence and solar day length. It also includes examples of calculating the angle of incidence and sunshine hours at different locations and dates. The document is intended to outline the syllabus and learning outcomes for a course on renewable energy systems with a focus on solar energy.
Energía solar fotovoltaica, elementos y componentes para la instalación y gen...Fernando Riveros Ochoa
This document provides definitions and explanations of key solar energy and photovoltaic concepts. It discusses solar radiation fundamentals, different types of solar cells including monocrystalline silicon and cadmium telluride, and components of photovoltaic systems like modules, arrays, and charge controllers. It also defines solar metrics and measurement devices, photovoltaic principles, standards, and optimal module installation parameters.
Clarity index is defined as the ratio of radiation received on Earth's surface compared to radiation beyond the atmosphere, and can range from 0.1 to 0.7. Concentration ratio is the ratio of solar power per unit area of a concentrator surface to a reference area, and can be up to 100 for parabolic trough collectors. Solar insolation is the solar radiation received on a horizontal surface, and depends on daily/seasonal variation, atmospheric clarity, shadows, latitude, exposed area, and tilt angle of solar panels. Pyrheliometers measure direct solar radiation flux, while pyranometers measure direct and diffuse radiation from the whole hemisphere. Solar radiation data contains information on whether values are measured or computed,
Principles of Solar radiation unit 1- Renewable Energy sourcesRamesh Thiagarajan
The document discusses solar energy and its various applications. It begins by explaining that solar energy is radiant light and heat from the sun that is harnessed using technologies to capture and distribute it. It then provides details on the different types of solar technologies, including passive solar and active solar. It also discusses topics like the amount of solar radiation the Earth receives, how solar radiation is characterized, and instruments used to measure solar radiation. The document then covers environmental impacts of solar power generation and steps that can be taken to address those impacts. Finally, it discusses additional topics such as the physics of the sun, characteristics of the sun, and types of solar collectors.
Dr. Patel Badari Narayana, MGIT unit II Introduction to Solar Radiation badarinp
This document provides information about solar radiation and its use as a renewable energy source. It discusses how solar radiation reaches Earth from the Sun, how the solar spectrum is affected by the atmosphere, and how to estimate the amount of solar radiation available at a given location and time. It also describes how to model the Sun's position in the sky and use sun path diagrams to assess solar access and shading issues at a site. The goal is to understand solar resources in order to effectively utilize solar energy technologies.
This document discusses key concepts related to solar radiation geometry. It begins by providing background on the sun and how it generates enormous amounts of energy. It then discusses how solar radiation reaches the Earth's atmosphere and surface. Key angles used in solar radiation analysis are defined, including latitude, declination, hour angle, and others. The timing of solstices and equinoxes is explained by the changing declination angle throughout the year. Factors like direct and diffuse radiation, spectral distribution, and how solar radiation is attenuated in the atmosphere are also summarized.
This document discusses solar energy and its applications. It covers topics like solar radiation components, applications of solar energy in areas like solar heating and cooling and power generation, and factors that affect solar radiation intensity like geographical location and weather conditions. It also provides information on concepts like extraterrestrial solar radiation, solar collectors, and how solar geometry and angles help determine the amount of direct radiation received on Earth's surface.
The document discusses key concepts related to solar radiation and quantifying solar energy potential. It defines terms like irradiation, insolation, irradiance, and peak sun hours. It describes how solar radiation is affected by factors like the Earth's atmosphere, seasons, and time of day. Diagrams show the sun's varying position and how solar panel orientation and tilt angle are important for maximizing energy capture. Locations experience different levels of solar resource throughout the year based on latitude and other geographical factors.
This document discusses solar energy and the structure and composition of the sun. It provides details on:
1) The core, radiation zone, convection zone, photosphere, chromosphere, transition layer, and corona of the sun and their respective temperatures and densities.
2) The concept of solar constant and how the amount of solar radiation reaching Earth varies with location and seasons.
3) Different types of solar collectors like flat plate and concentrating collectors and their uses for low to high temperature applications.
4) Key angles used in solar energy like the altitude, azimuth, and zenith angles and how they are calculated based on factors like latitude and day of the year.
The document discusses solar radiation and the solar constant. It defines the solar constant as the amount of incoming solar radiation per unit area measured outside Earth's atmosphere. The solar constant includes all types of solar radiation, not just visible light. It is measured as approximately 1370 watts per square meter and can vary up to 3% due to Earth's elliptical orbit. The document also discusses methods for estimating solar radiation levels, such as using the Augstrom correlation equation to calculate monthly average daily global radiation based on factors like sunshine hours and extra-terrestrial solar radiation.
Unit 2 - Solar Enerdknnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn...KavineshKumarS
The document discusses solar energy and its advantages and challenges. It begins by explaining that the sun is a hot gaseous sphere about 1.5x108 km from Earth. Solar energy reaches Earth in 8 minutes and 20 seconds. It then lists some key advantages of solar energy, such as its large size and clean nature, but also challenges like its dilute and varying availability. The document goes on to describe solar geometry concepts like declination angle, inclination angle, and zenith angle. It also summarizes different types of solar collectors like flat plate and evacuated tube collectors.
A description of solar radiation and how it is measured using pyranometers and other instruments, with a challenge for future makers. These measurements are needed for solar energy applications from electricity to solar cooking for refugees. A new ISO standard now provides a way to make fair comparisons of solar cookers. This method uses solar irradiance measurements to standardize the data for use anywhere in the world.
The sun is the primary energy source for Earth's climate system. It emits radiation isotropically that decreases with the inverse square of distance. At the top of the atmosphere, the solar irradiance is approximately 1361 W/m^2. The atmosphere absorbs and transmits parts of the solar spectrum. Earth's climate is maintained by a balance between absorbed solar radiation and outgoing terrestrial radiation. There are spatial and seasonal variations in this energy budget due to Earth's orbit and tilt.
This talk was given to Airdrie Astronomy Association on 22 March 2013. Some of the material was borrowed from Daniel Mueller (ESA) and the Solar Orbiter team. More information on Solar Orbiter can be found at http://sci.esa.int/solarorbiter
Este informe técnico analiza los datos de radiación solar medidos en la estación de STATION entre diciembre de 2005 y julio de 2009. Se realiza un análisis de calidad de los datos mediante filtros físicos y comparaciones entre las componentes medidas para verificar su precisión. También se comparan los datos con los de otras 5 estaciones cercanas y con un modelo de cielo despejado para validar la calidad de las mediciones a lo largo de los años.
Solar radiation ground measured data quality assessment reportIrSOLaV Pomares
This technical report analyzes radiometric data measured at a site in XXX from June 2011 to May 2012. It assesses data quality using various filters and comparisons to clear sky models. Global, diffuse, and direct normal irradiance were measured. The methodology section describes transforming time to true solar time, calculating hourly/daily averages, and quality analysis including physical limits checks and cross-component relationship checks. Graphs of measured and clear sky data are presented and used to visually inspect data quality.
Typical Meteorological Year Report for CSP, CPV and PV solar plantsIrSOLaV Pomares
This technical report analyzes the solar resource available at a site in Northern Cape, South Africa selected to host a solar thermal power plant. It presents a typical meteorological year (TMY) developed using 12 years of hourly solar radiation data for the site. The TMY is generated using a methodology that selects the most representative month from each year for key meteorological variables. It is comprised of months from 2007 to 2010 that best match the long-term averages for global horizontal and direct normal solar radiation at the site. The TMY and long-term averages are presented and show a close match in monthly and daily solar radiation patterns for use in modeling solar power production at the site.
Technical report site assessment of solar resource for a csp plant. correctio...IrSOLaV Pomares
This technical report summarizes a solar resource assessment for a CSP solar project site in Morocco. It details the methodology used by IrSOLaV to estimate solar radiation from satellite images, which has been validated against ground measurements. IrSOLaV corrects initial satellite estimates using on-site meteorological station data, achieving hourly and daily GHI and DNI estimation uncertainties of 12-18% and 5-10%, respectively. The report presents satellite-derived solar radiation data for the project site location from 2011-2013 and compares it to on-site pyranometer and pyrheliometer measurements.
Forecasting commercial services from S2M - Juan Liria (Sun2Market)IrSOLaV Pomares
Sun to Market Solutions was founded to provide independent technical support and engineering services for the growing solar power sector. It has over 25 engineers located across five continents with experience conducting studies in over 30 countries. Sun to Market Solutions has become a leading global advisor for the solar power industry. It developed a nowcasting system that provides short-term weather forecasts up to 24 hours in advance to help optimize performance of solar power plants and their integration with the electric grid. The nowcasting system collects and processes data from sky cameras, weather stations, satellites and numerical models to predict direct normal irradiation levels with an accuracy of within ±150 W/m2.
Future guidelines the meteorological view - Isabel Martínez (AEMet)IrSOLaV Pomares
This document discusses nowcasting and forecasting of solar irradiance using meteorological data. Nowcasting uses observations from the past 6 hours to predict clouds and irradiance up to 2 hours ahead for a specific site. Forecasting uses numerical weather prediction models to predict clouds and irradiance out to days or weeks ahead on regional to global scales. The document outlines various nowcasting techniques including the use of sky cameras, satellites, and neural networks. It also describes several forecast models run operationally at ECMWF and AEMET including HIRLAM, HARMONIE, and the ECMWF model. Prognostic aerosols are also modeled to improve irradiance forecasts.
Future guidelines on solar forecasting the research view - David Pozo (Univer...IrSOLaV Pomares
The document discusses solar radiation forecasting research conducted by the MATRAS solar radiation and atmosphere modelling group at the University of Jaen. The group has developed facilities for measuring and forecasting direct normal irradiance (DNI) using sky cameras, ceilometers and numerical weather prediction models. Their research aims to improve short-term DNI nowcasting and forecasting up to 72 hours ahead for applications such as solar power plant operation and electricity market participation. They are also investigating how to optimally balance solar and wind power resources to reduce production variability.
Forecasting commercial services from IrSOLaV - Luis Martin (IRSOLAV)IrSOLaV Pomares
IrSOLaV is a spin-off company founded in 2007 that provides solar radiation data and forecasting services using satellite imagery. It has participated in over 3.4GW of solar energy projects worldwide. IrSOLaV's products include time series data, reports, and maps of solar radiation. It also provides short-term (72 hours) and nowcasting (6 hours) forecasts of solar radiation. IrSOLaV conducts research partnerships and has offices in Spain, India, and Chile.
Managing the energy purchasing - Jorge gonzalez (Gesternova)IrSOLaV Pomares
Gesternova is an energy company that supports renewable energy development in Spain. They offer renewable energy to customers and help renewable energy producers connect to the grid and register with agencies to receive payments. There are several steps and agencies involved in connecting a solar plant to the grid and ensuring the plant owner receives payment for the electricity generated. Gesternova assists plant owners with registration, forecasting energy output, and interacting with grid operators and energy market agencies to ensure payments are processed accurately and on time.
Forecasting energy fo pv system - Miguel Martínez (Wenner Solar)IrSOLaV Pomares
Este documento presenta un taller sobre la predicción de la energía de sistemas fotovoltaicos. Incluye información sobre la predicción de la producción eléctrica de plantas fotovoltaicas, la influencia del mantenimiento en la producción y una visión general del sector fotovoltaico. El documento también proporciona detalles sobre el análisis inicial, el estudio de radiación y el rendimiento energético necesarios para predecir la producción de energía de una planta fotovoltaica.
Gemasolar a thermal solar power plant with 15 hours, Ignacio Burgaleta (Torre...IrSOLaV Pomares
The Gemasolar plant is a 19.9 MW solar thermal power plant in Spain that uses a central tower receiver with molten salt storage. It has over 2,600 heliostat mirrors that focus sunlight onto the receiver to heat molten salt to 565°C. The heated salt is then stored in tanks for up to 15 hours. This allows electricity production both during sunlight and after sunset. The plant began commercial operation in 2011 and has consistently exceeded performance guarantees, producing electricity continuously for over 12 days. Future, larger plants are planned to achieve even greater economies of scale.
Solar Thermal Power Plant with Thermal Storage - Ignacio Burgaleta (Torresol ...IrSOLaV Pomares
Torresol Energy operates several solar thermal power plants in Spain that use parabolic trough collectors and central tower technology. These plants include molten salt storage systems to allow electricity production when the sun is not shining. The document discusses Torresol Energy's experience with molten salt storage, including the advantages it provides in improving plant efficiency and enabling dispatchable solar power. It also describes the components and operation of the company's 50 MW parabolic trough plant with 7 hours of thermal storage. Accurate forecasting of solar irradiance and clouds is important for optimizing plant operations and grid integration of the solar power.
General situation of solar thermal energy - Eduardo Iglesias (Protermosolar)IrSOLaV Pomares
1) Solar thermal energy has potential for large-scale deployment as a carbon-free electricity source but currently only has 3 GW installed globally.
2) In Spain, solar thermal provided over 500 GWh in July 2012 and its economic impact in 2012 included over 1.8 billion euros in GDP contribution and nearly 18,000 jobs.
3) For solar thermal to reach its full potential, costs must continue to decline as deployment increases, with projections of 14-25 euro cents/kWh by 2030 as the industry matures and capacity grows towards 300 GW.
The CECRE: Making renewable energy technologies compatible with the security ...IrSOLaV Pomares
Red Eléctrica de España is the Spanish transmission system operator. It operates and maintains the transmission grid to ensure security of electricity supply. Renewable energy sources now account for 39% of Spain's installed capacity, including 22.6% from wind and 4.4% from solar PV. Integrating high levels of renewable energy presents challenges like variability in generation, lack of observability and controllability, and impacts on grid constraints and voltage control. The CECRE control center helps address these issues by providing centralized monitoring and control of renewable facilities.
Workshop on Applications of Solar Radiation Forecasting - Introduction - Jesú...IrSOLaV Pomares
This document provides an overview of solar radiation forecasting techniques and related activities. It discusses (1) the classification of forecasting methods, including very short-term nowcasting using sky imagers and satellite images, and forecasting with numerical weather prediction models, (2) Ciemat's involvement in solar forecasting research through IEA Tasks 36 and 46, benchmarking different methods, and (3) Ciemat's role in the DNICast and COST Wire projects which aim to improve techniques for direct normal irradiance forecasting and integrate forecasts with power plant and grid models.
The document outlines the agenda for a workshop on applications of solar forecasting held at CIEMAT on June 11, 2013. The workshop covered topics such as forecasting needs for solar energy production, managing energy from solar power plants and photovoltaic systems, commercial solar forecasting services, and future guidelines on solar forecasting from research and meteorological perspectives. Presentations were given by experts from universities, research institutions, solar energy companies, and meteorological organizations on integrating solar forecasting into energy management, electricity markets, and power plant operations.
Assessment and evaluation of solar resources adb courseIrSOLaV Pomares
This document discusses the assessment and evaluation of solar resources. It covers topics like solar geometry, interaction of solar radiation with the atmosphere, measurement of solar radiation, and databases of solar radiation. Key points include how solar position varies daily and yearly due to Earth's orbit and rotation, atmospheric effects on solar irradiance like scattering, absorption and reflection, and parameters used to characterize solar resources like extraterrestrial and global irradiance. The goal is to provide tools to help evaluate solar power projects.
1. The document discusses global solar radiation forecasting techniques used by the Spanish National Weather Service.
2. It outlines various statistical models for predicting clearness index, lost component, and qualitative predictions up to 6 hours in advance.
3. The best models were neural networks for clearness index and lost component predictions, achieving up to 28% improvement over persistence.
The document provides an overview of solar resource evaluation methodology. It discusses the need to evaluate solar radiation for energy system studies and compares classical evaluation using measurements to evaluation from satellite images. The proposed procedure involves determining what type of data is needed like hourly or monthly time series data or maps. It then describes whether satellite information or measurements will be used. The document also covers topics like solar radiation characteristics, components, clear sky models, and methods for measuring solar radiation including typical monitoring station setups.
Solar radiation forecasting with wrf model in the iberian peninsulaIrSOLaV Pomares
This document summarizes research validating solar radiation forecasting models in the Iberian Peninsula. It evaluates the ECMWF ERA-40 global model and the WRF mesoscale model at hourly and daily resolutions against ground measurements. The ECMWF model underestimates daily solar radiation with errors up to 39.55%. The WRF model has hourly errors ranging from 30-98% and daily errors from 23-89%. While WRF with NCEP data fails to accurately reproduce synoptic situations, using ECMWF data inputs may improve forecasts. However, cloud movement remains challenging to predict deterministically. Further progress is needed to meet a 20% error requirement for hourly solar forecasts in Spain.
Solar radiation forecasting with wrf model in the iberian peninsula
Appraisal of solar resources
1. Appraisal of Solar
Resources
LUIS MARTIN POMARES
IrSOLaV
Solar Technology Advisors S.L.
Plaza de Manolete, 2, 11-C
28020 Madrid
Tel. +34 91 383 58 20
February, 2013
2. SOLAR TECHNOLOGY ADVISORS
Index
• INTRODUCTION
• SOLAR RADIATION CHARACTERISTICS
• CLASSICAL EVALUATION OF SOLAR RADIATION
• INTERACTION OF SOLAR RADIATION WITH THE
ATMOSPHERE
• STUDY OF DIRECT SOLAR RADIATION
• SOLAR RADIATION DATA
• SOLAR RADIATION DATA FROM SATELLITE AND
NWPM
• GENERATION OF TIME SERIES FOR SIMULATION
• SOLAR RADIATION DATABASES ON THE INTERNET
3. SOLAR TECHNOLOGY ADVISORS
Index
• INTRODUCTION
• SOLAR RADIATION CHARACTERISTICS
• CLASSICAL EVALUATION OF SOLAR RADIATION
• INTERACTION OF SOLAR RADIATION WITH THE
ATMOSPHERE
• STUDY OF DIRECT SOLAR RADIATION
• SOLAR RADIATION DATA
• SOLAR RADIATION DATA FROM SATELLITE AND
NWPM
• GENERATION OF TIME SERIES FOR SIMULATION
• SOLAR RADIATION DATABASES ON THE INTERNET
4. SOLAR TECHNOLOGY ADVISORS
Introduction
Solar resources evaluation is a necessary first step for
the study of any energy system.
The objective is the determination of the solar radiation
collected in a specific site, for its use in a specific solar
technology.
As inputs, it is necessary to have information related to
the source and to the technology.
The methodologies can be classified as: classical
evaluation (from measurements), and evaluation from
satellite images.
5. SOLAR TECHNOLOGY ADVISORS
Introduction
To obtain solar radiation data it is possible:
To measure it: global?, diffuse? Direct normal?
And / or derive the needed variable (classical evaluation)
To estimate using satellite images or NWPM (mainly
global).
And / or derive the needed variable (classical evaluation)
Once solar radiation data are available, the
generation of a series for simulation it is
possible.
As a first step of all this subjects, it is necessary
to study the nature of the solar resource.
6. SOLAR TECHNOLOGY ADVISORS
Index
• INTRODUCTION
• SOLAR RADIATION CHARACTERISTICS
• CLASSICAL EVALUATION OF SOLAR RADIATION
• INTERACTION OF SOLAR RADIATION WITH THE
ATMOSPHERE
• STUDY OF DIRECT SOLAR RADIATION
• SOLAR RADIATION DATA
• SOLAR RADIATION DATA FROM SATELLITE AND
NWPM
• GENERATION OF TIME SERIES FOR SIMULATION
• SOLAR RADIATION DATABASES ON THE INTERNET
7. SOLAR TECHNOLOGY ADVISORS
SOLAR RADIATION
CHARACTERISTICS
Solar energy reaches the earth in a
discontinuous form, showing cycles or
periods:
Daily cycle: accounts for 50% of the total
availability of daily hours.
Another effect of the daily cycle is the modulation
of the received energy throughout the day.
Seasonal cycle: modulation of the received energy
throughout the year.
8. SOLAR TECHNOLOGY ADVISORS
SOLAR RADIATION
CHARACTERISTICS: Low Density
The maximum possible amount of solar radiation
received by the surface of the atmosphere at 1
AU is 1367 W/m2
Large surfaces are needed to achieve high power
outputs.
To increase the density concentration should be used.
A limitation to concentration is that this only has any
effect on the direct component of solar radiation.
9. SOLAR TECHNOLOGY ADVISORS
SOLAR RADIATION CHARACTERISTICS:
Geographic variation
In clear sky conditions: the solar radiation
depends mainly on the latitude.
Latitude effect is equivalent to the modification of
the angle of incidence of solar radiation.
For the modulation of the received energy the
following can be used:
Solar tracker
Plane inclination
The inclination of the reception plane means:
Modification of the latitude effect
Modification of the annual distribution.
10. SOLAR TECHNOLOGY ADVISORS
SOLAR RADIATION CHARACTERISTICS:
Random situations
Solar radiation on the earth´s surface is modulated by climatic
conditions.
Clear sky conditions are not common.
The latitude indicates a maximum range, but the energy
received is determined by local climatic conditions.
11. SOLAR TECHNOLOGY ADVISORS
Index
• INTRODUCTION
• SOLAR RADIATION CHARACTERISTICS
• CLASSICAL EVALUATION OF SOLAR RADIATION
• INTERACTION OF SOLAR RADIATION WITH THE
ATMOSPHERE
• STUDY OF DIRECT SOLAR RADIATION
• SOLAR RADIATION DATA
• SOLAR RADIATION DATA FROM SATELLITE AND
NWPM
• GENERATION OF TIME SERIES FOR SIMULATION
• SOLAR RADIATION DATABASES ON THE INTERNET
12. SOLAR TECHNOLOGY ADVISORS
SUN-EARTH RELATIONSHIPS: Sun-earth distance
The earth revolves around the Sun in an elliptical
orbit, with the Sun in one of its foci.
The amount of incoming solar radiation to the earth
is inversely proportional to the sun´s square distance.
The distance is measured in astronomical units (AU)
equivalent to the mean earth-sun distance.
13. SOLAR TECHNOLOGY ADVISORS
Solar constant and solar geometry
Is the amount of solar energy incident in 1m2 of
surface perpendicularly exposed to the solar rays and
placed at 1 AU of distance.
Changes slightly with time, but can be considered as
constant.
Ion = 1367 W/m2.(WRC).
The solar radiation has participation in
several electromagnetic spectral ranges.
Solar geometry is well known
We can estimate with high accuracy the solar irradiation at the
top of the atmosphere at every moment and every place
14. SOLAR TECHNOLOGY ADVISORS
SUN-EARTH RELATIONSHIPS:
Sun declination
Considering the ecliptic plane (ECLP) as the plane of
earth´s revolution around the Sun and the equatorial
plane (EQUP) as the plane containing the equator:
Polar axis is tilted 23.5º with respect to the
perpendicular of the ECLP.
ECLP and EQUP cross in the
equinoxes and the distance is
maximum in the solstices.
The angle in a specific moment
between both planes is called
DECLINATION
15. SOLAR TECHNOLOGY ADVISORS
SUN-EARTH RELATIONSHIPS: Relative
position sun-horizontal surface
These are trigonometric relationships between the sun´s position in
the sky and specific coordinates on the earth surface
In a specific moment the following must
SOL
ZENITH
be considered:
• zenith (θ ) angle and solar
TRAYECTORIA SOLAR
(+) MAÑANA W
(-) ESTE
θz
z elevation (α)
• azimuth (ψ) = angle between the
-ψ ψ α observer meridian and the solar meridian
S
0
N
• hourly angle (ω) = angle between the
+ψ sun position and the south meridian
PROYECCION DE LA
TRAYECTORIA SOLAR
15º=1hour; +E /-W.
E • Sunrise angle (ωs) = sunset angle
(horizon)
16. SOLAR TECHNOLOGY ADVISORS
Hourly radiation over horizontal
surface
One specific day: the extraterrestrial
radiation over a perpendicular surface
to the Sun´s rays is expressed as:
Placing this surface over the earth, it
is necessary to take into account the
cosine of the incident angle:
17. SOLAR TECHNOLOGY ADVISORS
Index
• INTRODUCTION
• SOLAR RADIATION CHARACTERISTICS
• CLASSICAL EVALUATION OF SOLAR RADIATION
• INTERACTION OF SOLAR RADIATION WITH THE
ATMOSPHERE
• STUDY OF DIRECT SOLAR RADIATION
• SOLAR RADIATION DATA
• SOLAR RADIATION DATA FROM SATELLITE AND
NWPM
• GENERATION OF TIME SERIES FOR SIMULATION
• SOLAR RADIATION DATABASES ON THE INTERNET
18. SOLAR TECHNOLOGY ADVISORS
Hourly radiation over horizontal
surface
The main phenomena that take place when the solar
radiation through the atmosphere are:
Absorption by the atmospheric components.
Diffusion or scattering.
19. SOLAR TECHNOLOGY ADVISORS
Interaction of solar radiation with
the atmosphere
Radiation at the top of atmosphere
Absorption (ca. 1%)
Ozone.……….…....
Rayleigh scattering and absorption (ca. 15%)
Air molecules..……
Scatter and Absorption (ca. 15%, max. 100%)
Aerosol…….………..…...……
Clouds………….……….. Reflection, Scatter, Absorption (max. 100%)
Water Vapor…….……...……… Absorption (ca. 15%)
Direct normal irradiance at ground
20. SOLAR TECHNOLOGY ADVISORS
Hourly radiation over horizontal
surface
The main phenomena that take place when the solar
radiation through the atmosphere are:
Absorption by the atmospheric components.
Diffusion or scattering.
As a consequence, the solar radiation has modified its
nature, and mainly its directional component:
G = I cos θ + D + R
21. SOLAR TECHNOLOGY ADVISORS
Solar radiation components
RADIATION REFLECTED BY CLOUDS
GROUND ALBEDO
ABSORPTION
SCATTERING
DIRECT NORMAL RADIATION
DIFUSE RADIATION
23. SOLAR TECHNOLOGY ADVISORS
Index
• INTRODUCTION
• SOLAR RADIATION CHARACTERISTICS
• CLASSICAL EVALUATION OF SOLAR RADIATION
• INTERACTION OF SOLAR RADIATION WITH THE
ATMOSPHERE
• STUDY OF DIRECT SOLAR RADIATION
• SOLAR RADIATION DATA
• SOLAR RADIATION DATA FROM SATELLITE AND
NWPM
• GENERATION OF TIME SERIES FOR SIMULATION
• SOLAR RADIATION DATABASES ON THE INTERNET
24. SOLAR TECHNOLOGY ADVISORS
SOLAR RADIATION ON THE EARTH SURF
Direct solar radiation
Is the radiation coming directly from the Sun disk.
Have a vector character and can be concentrated.
Can be 90% of the solar radiation on clear sky
days, and can be null in cloud covered days.
As a directional component, the contribution on a
surface is the perpendicular projection over this
surface: beam radiation is the radiation perpendicular
to the sun's rays, then:
Ih = I cos θ
With solar trackers it can be maximised.
I ≅ DNI
25. SOLAR TECHNOLOGY ADVISORS
SOLAR RADIATION ON THE EARTH SURF
Diffuse solar radiation
A part of the solar radiation that is lost when it is
absorbed by the atmospheric components. Another
part is reflected by these components producing
direction changes and energy reduction.
Diffuse radiation = the part of this radiation that
reaches the earth's surface.
Diffuse radiation has three components:
Circumsolar
Horizon band
Blue sky
26. SOLAR TECHNOLOGY ADVISORS
SOLAR RADIATION ON THE EARTH SURF
Reflected solar radiation
Is the radiation coming from the reflection of the
solar radiation on the ground or on other nearby
surfaces.
Usually is small, but can be around 40% of the solar
radiation.
27. SOLAR TECHNOLOGY ADVISORS
Ley of Beer
In I0 e( k L ) I0 e( m ) I0 T
In In d I0 e( k L ) d ISC e m
Clear sky models or transmitance models
Bn I CS (TRToTgTwTa 0.013) Yang
Bn ICS exp[0.8662 TLAM 2 mp R ]
C
ESRA
28. SOLAR TECHNOLOGY ADVISORS
The concept of optical mass
Aproximation to plane-
parallel
1
m
cos
Karsten equation
m (sin 0.15( 3.885)1.253 )1
30. SOLAR TECHNOLOGY ADVISORS
Sensibility of ESRA model to TL
Influence of TLINKE and altitude above sea level on DNI for clear sky
Dia juliano=200, z=500, Lat=37º N Long=-2º E TL=4, dia juliano=200, Lat=37º N Long=-2º E
1200 1000
TL=2 z=0 m
TL=4 900 z=500 m
1000 TL=6 z=1000 m
800
700
800
DNI (Wh m-2)
600
DNI (Wh m-2)
600 500
400
400
300
200
200
100
0 0
0 2 4 6 8 10 12 14 16 18 20 22 24 0 5 10 15 20 25
Hora Hora
31. SOLAR TECHNOLOGY ADVISORS
Components and non-dimensioanl
indexes
Components of solar radiation in horizontal surface
IG IB cos ID
Clear sky or transparency index
IG
kt
I0
Difuse radiation fraction
ID
kd
IG
Beam radiation transmitance
IB
kb
I0
32. SOLAR TECHNOLOGY ADVISORS
Estimation of beam solar radaition
Correlations to estimate difuse radiation fraction
G (1 kd )
Ib 1.0 0.09kt kt 0.22
sen( )
kd 0.9511 1.1604kt 4.388kt 2 16.638kt 3 12.336kt 4 0.22 kt 0.8
0.165 k 0.8
t
Correlations to estimate beam transmitance
I b kb I o kb 0.002 0.059kt 0.994kt 2 5.205kt 3 15.307kt 4 10.627kt 5
33. SOLAR TECHNOLOGY ADVISORS
SOLAR RADIATION ON THE EARTH SURF
Phenomena through the atmosphere
Spectral distribution of solar
radiation for a s standard atmosphere
-- an "average" atmosphere with
specified characteristics -- compared
to the extraterrestrial radiation at the
average Earth/sun distance.
Direct normal radiation
Diffuse radiation
The relationship between direct and
diffuse radiation depends on the
position of the sun in the sky. The sun
in Figure is at an elevation angle of
about 42º, giving a relative air mass
of about 1.5. (If the sun is directly
overhead, the relative air mass is 1,
by definition.)
34. SOLAR TECHNOLOGY ADVISORS
Index
• INTRODUCTION
• SOLAR RADIATION CHARACTERISTICS
• CLASSICAL EVALUATION OF SOLAR RADIATION
• INTERACTION OF SOLAR RADIATION WITH THE
ATMOSPHERE
• STUDY OF DIRECT SOLAR RADIATION
• SOLAR RADIATION DATA
• SOLAR RADIATION DATA FROM SATELLITE AND
NWPM
• GENERATION OF TIME SERIES FOR SIMULATION
• SOLAR RADIATION DATABASES ON THE INTERNET
35. SOLAR TECHNOLOGY ADVISORS
SOLAR RADIATION DATA
Due to the climatic factors that modify the solar radiation received on
the earth´s surface, it is impossible to know beforehand the energy
that will be received by the system.
Then it is necessary to use data of solar radiation of the past years.
In the evaluation of solar radiation on a specific site, can assume two
cases:
In the evaluation of solar radiation on a specific site, can assume two
cases:
Estimation of the solar radiation (global or its components), in sites
with any information related to solar radiation:
FROM MEASUREMENTS
(AND/ OR USING CLASSICAL EVALUATION MODELS)
The estimation of the solar radiation and its components, in sites
without any previous information.
EVALUATION FROM SATELLITE IMAGES
EVALUATION FROM NWPM
(AND/ OR USING CLASSICAL EVALUATION MODELS)
36. SOLAR TECHNOLOGY ADVISORS
MEASUREMENTS OF SOLAR RADIATION
UNCERTAINTY OF ONE INSTRUMENT Distribution of the observations.
If there are n comparisons of an operational instrument holding
constant the measured variable and all other relevant parameters, and
establishing a true value using a reference standard, the results can be
represented as in Fig.
The accuracy with which a meteorological variable should be measured
changes with the specific purpose which it is intended that
measure. For most operational and research purposes, the
determination of required accuracy aims to ensure compatibility of
data, both in space and time. In cases where it is difficult to ascertain
the absolute accuracy, it is usually enough to take measures to ensure
that the data are sufficiently compatible for users.
38. SOLAR TECHNOLOGY ADVISORS
Measuring Solar Radiation:
Pyrheliometers Direct Normal Radiation
EKO MS-54
Measures direct beam irradiance
Typically used for calibration transfers
Normally defined with an opening angle of 5 Middleton DN5
If used in conjunction with pyranometers, the
optical flat protecting entrance should match the
optical material of the pyranometer domes
Relatively easy to characterize
4 major manufacturers:
• EKO Instruments (Japan)
• Eppley Instruments (USA)
• Kipp & Zonen (Netherlands)
• Middleton Solar [Carter Scott Design] (Australia)
Normally mounted on passive or active solar
tracking systems
39. SOLAR TECHNOLOGY ADVISORS
Measuring Solar Radiation: Pyranometers
Global Horizontal Radiation
Tilted Irradiance
Most pyranometers use a thermopile as means of converting solar
irradiance into an electrical signal.
Silicon cell pyranometers are also available, but are not recommended b
WMO.
Advantage of the thermopile is that it is spectrally neutral across the
entire solar spectrum (domes may have spectral dependencies).
Disadvantage is that the output is temperature dependent and the
instruments must ‘create’ a cold junction.
40. SOLAR TECHNOLOGY ADVISORS
Measuring Solar Radiation: Silicon
Pyranometers
Instrument’s spectral response is non-linear and does not match solar
spectrum.
General calibrations are through comparison with pyranometers, therefore
there are spectral mismatch problems.
LiCor is the primary instrument manufacturer and recognizes these
problems:
“The spectral response of the LI-200 does not include the entire solar
spectrum, so it must be used in the same lighting conditions as those under
which it was calibrated.”
–Pyranometer sensors are calibrated
against an Eppley Precision Spectral
Pyranometer (PSP) under natural daylight
conditions. Typical error under these
conditions is ±5%. (LiCor)
–Similar problems arise when using
sensors calibrated in one climate regime
and used in a different regime.
41. SOLAR TECHNOLOGY ADVISORS
Rotating Shadowband Radiometer RSR2
LI-COR Terrestrial Radiation Sensors
Irradiance Inc. (www.irradiance.com)
LI-200 Pyranometer is a silicon photodiode
calibrated from LI-COR ±5%
RSR2 Head unit includes a moving
shadowband that momentarily casts a
shadow over a LI-200 pyranometer
Motor controller contains circuit to control
the exact movement of shadowband LI-200 Pyranometer
Correction provided by Algorithm
Measurement:
Global Horizontal Irradiance
Diffuse Horizontal Irradiance
Calculation:
Direct Normal Irradiance
RSR2 Headunit RSR2 Motor Controller
44. SOLAR TECHNOLOGY ADVISORS
Data logger
For continuous recording automatic data logger are required.
The main requirement in terms of exposure must be the lack of
obstructions to the solar beam at all times and seasons.
Furthermore, the exact location of the instrument must be chosen so
that the incidence of fog, smoke and air pollution is as representative
as possible of the surrounding geographic area.
46. SOLAR TECHNOLOGY ADVISORS
Measurement recomendations
Know exactly what temporal reference of the
masurements you are using (TSV, GMT, Local etc)
Register with enough temporal resolution, almost 10
minutes to register the dinamic of cloud transients.
Follow BSRN recomendation for maintenance of
instruments. Cleaning every day radiometers, calibrate
once per year each instrument,…
Secure the relation G=B cos θ + D. Some solar trackers
have embeded this filter in its program to activetes
realtime alarms when measurement is worng.
47. SOLAR TECHNOLOGY ADVISORS
Index
• INTRODUCTION
• SOLAR RADIATION CHARACTERISTICS
• CLASSICAL EVALUATION OF SOLAR RADIATION
• INTERACTION OF SOLAR RADIATION WITH THE
ATMOSPHERE
• STUDY OF DIRECT SOLAR RADIATION
• SOLAR RADIATION DATA
• SOLAR RADIATION DATA FROM SATELLITE AND
NWPM
• GENERATION OF TIME SERIES FOR SIMULATION
• SOLAR RADIATION DATABASES ON THE INTERNET
48. SOLAR TECHNOLOGY ADVISORS
SOLAR RADIATION DATA FROM SATELLITE AND
NWP MODELS
FROM SATELLITE
The satellite
Methodology
Example of models application
FROM NWP MODELS
General overview
Main models
Main characteristics
50. SOLAR TECHNOLOGY ADVISORS
Satellite classification
According to the type of orbit :
Polar satellites: placed in polar
orbits, modifying its
perspective and distance to the
earth. The resolutions of these
satellites are around 1m to
1km.
Geostationary satellites: placed in the geostationary orbit that is, the place
in the space where the earth's attraction force is null. It is an unique
circumference where all the geostationary satellites are situated in order
to cover the whole earth's surface. The resolutions of these satellites are
higher in the sub satellite point on the equator, and go decreasing in all
directions.
51. SOLAR TECHNOLOGY ADVISORS
Meteorological satellites
In meteorology studies frequents observations and with
high density on the earth’s surface are required.
Conventional systems do not provide a global cover.
An important tool to analyse the distribution of the
climatic system are the METEOROLOGICAL SATELITES.
These can be:
Polar satellites.
Geoestationary: In EUROPE and part of ASIA, the
system of geosttationary meteorolgical satellites
is called METEOSAT.
52. SOLAR TECHNOLOGY ADVISORS
Meteosat Satellite coverage
Meteosat Prime Meteosat East
Spatial resolution 2.5 km at sub satellite, eg. About 3x4 km in Europe
Temporal resolution 1h.
Current Coverage: Meteosat Prime up to 1991-2005,
Meteosat East 1999 - 2006
53. SOLAR TECHNOLOGY ADVISORS
SOLAR RADIATION DATA FROM SATELLITE:
ADVANTAGES
The geostationary satellites shows
simultaneously big land areas.
The information of these satellites is always
referred to the same window and can be put on
top.
There are the possibility to know previous
situations using satellite images of previous
years.
The utilization of the same detector to evaluate
the radiation in different places.
54. SOLAR TECHNOLOGY ADVISORS
Solar radiation derived from
satellite images
Satellite to irradiance: general procedure
• Meteosat – Goes - Mtsat
• 60’, 30’ or 15’ images in the visible
position assessment geometric
corrections – pixels averaging
model to obtain global irradiance
55. SOLAR TECHNOLOGY ADVISORS
Summary of the methodology
METHODOLOGY OF THE STATISTICAL MODELS:
• Cloud cover index determination.
• Hourly clearness index determination (hourly global radiation).
• Daily clearness index determination (daily global radiation).
BASED ON RELATIONSHIPS BETWEEN:
• The measurement of the solar radiation.
• The value of the digital count form the satellite image (corresponding
to the measures locations)
56. SOLAR TECHNOLOGY ADVISORS
Clearness index=Global radiation
The geostationary satellites shows simultaneously big
land areas.
A relationship is evaluated using the ground data
simultaneous to the satellite images. This relationship is
applied to the whole image.
As meaningful variables:
Cloud cover index.
Declination
57. SOLAR TECHNOLOGY ADVISORS
AOD (Aerosol Optical Depth
estimations)
Estimations from MODIS (Moderate Resolution
Imaging spectroradiometer) on NASA’s Terra satellite
http://earthobservatory.nasa.gov/
AOD and water vapor vertical content estimations from satellite
58. SOLAR TECHNOLOGY ADVISORS
SOLAR RADIATION DATA FROM SATELLITE AND
NWP MODELS
FROM SATELLITE
The satellite
Methodology
Example of models application
FROM NWP MODELS
General overview
Main models
Main characteristics
59. SOLAR TECHNOLOGY ADVISORS
SOLAR RADIATION DATA FROM NWP MODELS
Executed based on the initial conditions from which
differential equations describing the evolution of the
atmosphere are solved.
61. SOLAR TECHNOLOGY ADVISORS
Index
• INTRODUCTION
• SOLAR RADIATION CHARACTERISTICS
• CLASSICAL EVALUATION OF SOLAR RADIATION
• INTERACTION OF SOLAR RADIATION WITH THE
ATMOSPHERE
• STUDY OF DIRECT SOLAR RADIATION
• SOLAR RADIATION DATA
• SOLAR RADIATION DATA FROM SATELLITE AND
NWPM
• GENERATION OF TIME SERIES FOR
SIMULATION
• SOLAR RADIATION DATABASES ON THE INTERNET
62. SOLAR TECHNOLOGY ADVISORS
Generation of series for simulation
Typical Meteorological Year (TMY) is a methodology for such a
purpose that has evolved along the time.
The starting point was the method developed in Sandia National
lab that partially used the database SOLMET/ERSATZ (1951-1976)
[5] formed by 248 stations, from which 26 had available
measurements of solar radiation components for the EEUU.
The method consisted in the concatenation of typical months to
generate a year with 8760 values of the considered variables:
average, maximum and minimum temperature and dew
temperature, wind velocity and global solar irradiance.
Filkenstein-Schafer statistic was used to select typical months.
Several improvements and variations to the initial TMY
methodology have been suggested along the time yielding to
newer versions like TMY2 y TMY3.
63. SOLAR TECHNOLOGY ADVISORS
Generation of series for simulation
Nevertheless, the essence of the method remains practically
unchanged. However, TMY methodology was developed to create
typical meteorological years and not typical solar years, which
have, despite the similarity, a different meaning in the framework
of the CPS industry.
Since 2010 a selected group of Spanish institutions and companies
closely related to the CSP industry have been working within the
AENOR framework (Spanish Association for Standardization and
Certification) on standards for the industry.
Part of this work consists of the development of a methodology for
generating a year of solar irradiance data and other influencing
variables to be used by the CSP industry.
64. SOLAR TECHNOLOGY ADVISORS
Generation of series for simulation
Due to the wide range of different data that can be used for
generating the ASR six types of data have been established:
direct measured data
indirect measured data
derived data
synthetic data
satellite data and
data from numerical model (NWP model).
This distinction implies different request to the quality, usage and
treatment of the data according to its different nature.
Therefore, the procedure allows the generation of the ASR by
combining these kinds of data whenever the boundary conditions
of quality and representativeness are fulfilled
66. SOLAR TECHNOLOGY ADVISORS
Index
• INTRODUCTION
• SOLAR RADIATION CHARACTERISTICS
• CLASSICAL EVALUATION OF SOLAR RADIATION
• INTERACTION OF SOLAR RADIATION WITH THE
ATMOSPHERE
• STUDY OF DIRECT SOLAR RADIATION
• SOLAR RADIATION DATA
• SOLAR RADIATION DATA FROM SATELLITE AND
NWPM
• GENERATION OF TIME SERIES FOR SIMULATION
• SOLAR RADIATION DATABASES ON THE
INTERNET
69. SSE
Radiometric Databases: SSE from NASA
http://eosweb.larc.nasa.gov/sse/
Surface
Meteorology and
Solar Energy
(SSE) Datasets
And Web
interface
Monthly data
Free upon
Growing over the last 7 years to nearly 14,000
registration
users, nearly 6.4 million hits and 1.25 million 1ºx1º (120x120
data downloads
km) resolution
70. SOLAR TECHNOLOGY ADVISORS
Solar radiation derived from satellite images
SWERA Project
The SWERA project provides easy access to high quality renewable energy resource
information and data to users all around the world. Its goal is to help facilitate renewable
energy policy and investment by making high quality information freely available to key user
groups. SWERA products include Geographic Information Systems (GIS) and time series data
71. SOLAR TECHNOLOGY ADVISORS
Comercial data from satellite
• Irsolav
• Solemi (DLR)
• 3Tier
• Solargis
• ….
75. SOLAR TECHNOLOGY ADVISORS
IrSOLaV activities
Ciemat promoted a spin-off company for solar resource
characterization services (www.irsolav.com). Thus IrSOLaV
interacts with the industry needs and supply data and
consulting services on solar resource and also collaborates
with Ciemat in R&D.
IrSOLaV and Ciemat develops R&D programs in the solar
resource field and collaborates with international scientific
groups (DLR, NREL, NASA, JRC, CENER, Universities…)
through European projects (COST project) or other
initiatives (Task 46 SHC/IEA)
Within Spain IrSOLaV and CIEMAT collaborates with
universities (UAL, UJA, UPN) and support the industry
through agreements for doing specific research on solar
resource knowledge (forecasting, model
improvements, atmospheric physics, etc)