66 Mohakhali C/A, Dhaka-1216, Bangladesh
|
|
- Basil Lewis
- 6 years ago
- Views:
Transcription
1 2013 I Conference on ustainable Utilization and Development in ngineering and Technology Design of a olar Powered D treet ight: ffect of Panel s Mounting Angle and Traffic ensing anjana Ahmed #1, Ahmed Hosne Zenan *2, Nisat Tasneem #3, Mosaddequr Rahman #4 # Department of lectrical and lectronic ngineering, BRAC University 66 Mohakhali C/A, Dhaka-1216, Bangladesh 1 sanj.ahmed@gmail.com 2 a.h.zenan@gmail.com 3 nisat.tasneem@gmail.com 4 mosaddeq@bracu.ac.bd Abstract In this work, the effect of mounting angle of solar panels and traffic sensing on the requirement of system size, i.e., panel size and battery capacity, for a solar powered street light system is investigated. treet lights need more energy in winter than in summer due to longer winter nights. However, for a solar powered system, less energy is available in winter with less intense sunlight and shorter days. The mounting angle of panels has a great impact on the cumulative energy output of the panels. Our investigation shows that w yields maximum energy collection in summer and minimum energy collection in winter, a mounting angl 46 5 increases the energy collection in winter and yields more or less uniform energy collection throughout the year. Assuming a panel efficiency of 16%, an average cumulative energy output of 950 Wh/m 2 /day with about 5 8% variation throughout the year has been found with This results in about 9% reduction in the panel size than that required with a. Moreover, installing a traffic sensor in the lighting system will allow detection of traffic density, thereby operating the lamps at different intensity levels as per requirements. This will save energy wastage in time of low or no traffic and will further relax the requirement on system size. Keywords olar nergy, treet ight, Mounting Angle, Panel ize, Battery Capacity I. INTRODUCTION Renewable energy has been emerging as the main source of energy in many applications because of its several environmental, social and economic benefits over other fuel types. Considering the merits of renewable energy, a solar powered street lighting system will provide unmatched reliability and convenience for the public. Unlike wired street lamps, solar powered street lights are easy to install at any location, have no daily operational or post-installation cost and can be functional even during load shedding. The street lighting system comprises of a solar panel mounted at an angle that charges the battery through the charge controlling circuit during daytime. During night time, the battery supplies power to the D lamp through an D driver circuit. D lamps are the preferred lighting source considering their photometrics such as efficacy, life span, cost, efficiency and power consumption. The system will employ a traffic sensor to sense the volume of traffic and adjust the light intensity accordingly which will lead to considerable savings in energy consumed specially during the long winter nights. A traffic sensor can be easily implemented using an ultrasonic or radio-frequency sensor. Given the miniature size of the sensors, energy consumed by the sensors will be minimal compared to the D lamps. Designing an efficient solar powered street light system requires determining the minimum system sizes for the panels and the battery that can collect enough energy during the day to light the lamps during the night all through the year. This is challenging since the longer daylight hours of summer can easily provide the energy for lighting the street lights during the shorter nights, but in winter, nights are longer, thus requiring the street lights to operate for longer hours with short days providing less sunlight energy. One factor that greatly influences the energy collected by the panel is the angle at which the panel is mounted. Mounting the panels at the same angle as the inclination angle of the sun will result in maximum energy collection. As the sun s position keeps changing throughout the year, determining a mounting angle that is optimum for all the seasons is important for the system to be efficient and cost-effective, and will be discussed in detail in this paper. A ounting angle of he e the panel is aligne ith the sun s position fo the sp ing/fall seasons, is well suited to applications like solar home system which tries to maximise the energy supply for the whole the year. However, for a street lighting system, this will not yield an efficient system as it will result in minimum energy collection in winter when energy demand is maximum, thus requiring a large system size to meet the demand. This paper discusses the determination of solar irradiation and the cumulative energy collected during a day and subsequent determination of system size for different panel mounting angles in order to find a mounting angle that would require minimum system size. Further, the effect of controlling the light intensity by sensing the traffic volume on system size is also investigated. The rest of the paper has been organized in the following way: section 2 describes the /13/$ I 74
2 2013 I Conference on ustainable Utilization and Development in ngineering and Technology methodology for the determination of cumulative energy output of a panel for a fixed mounting angle; section 3 introduces the formula and the associated meteorological terminologies to calculate solar irradiation and the cumulative output energy density of panels mounted at fixed angle for different seasons; section 4 introduces the formulae and the associated parameters to calculate the panel size and battery capacity for systems with and without traffic sensing; section 5 gives the calculated results and discussions on the cumulative energy output of a panel in different seasons, mounted at different angles, and the effects of mounting angle and traffic sensing on system size. ection 6 makes concluding remarks. II. MTHODOOGY For maximum energy collection, panels should be pe pen icula to the inci ent sola a iation But the sun s position changes with different seasons as shown in Fig. 1. Although a tracker would negotiate automatically with the optimum direction to get the most of sunlight, it is costly and would need regular maintenance which is difficult to implement for a street lighting system. Keeping this in mind, we have employed a fixed tilt angle to the mounted panel. Implementing a fixed type needs to have a calculated angle since one tilt angle throughout the year must satisfy the requirement for all the four seasons. In order to determine the appropriate mounting angle, it is necessary to calculate the energy density or irradiation for winter, summer, spring and fall with different mounting angles. Using the calculated energy density for different mounting angles, corresponding system size can be determined using standard procedure. From the results of these calculations, appropriate mounting angle can be ascertained that results in minimum system size. Then the main task is to find the solar irradiance at any time that epen s on the sun s position at that pa ticula ti e As the sun s bea oves th ough the at osphe e the path covered by it, also known as the air mass (AM), varies depending on its angle with the vertical of the earth, called the zenith angle. The complement of the zenith angle is called solar altitude and can be expressed as function of the hour angle (determined by the time of the day), the declination angle the angle that the sun akes ith the ea th at 0 latitu e which depends on the day of the year, and the latitude angle. Thus, with the knowledge of solar altitude, solar irradiance at any time can be calculated which when integrated over time, from sunrise to sunset, gives the cumulative energy density for any particular day. Panel s effective a ea hich epen s on the sun s position an the panel s ounting angle also affects the total energy collected by the panel and has to be taken into account in the calculation of cumulative energy. By comparing the effective irradiation i.e. the energy density in different seasons at different mounting angles, the optimum angle can be ascertained. III. CACUATION OF CUMUATIV OUTPUT NRGY A. olar Irradiance and the Altitude Angle As sunlight passes through the atmosphere, much of it is N ummer W un pring/fall un Winter un Figure 1: Position of sun in different seasons scattered or absorbed by the atmospheric layers themselves. Depending on the length of path sunlight traverses through the atmosphere, the amount of absorbed or scattered sunlight varies. This path length is minimum with a vertical path directly to sea level and is designated an air mass one, expressed as AM1. However, for non-vertical sun angles, the rays of sun have to traverse extra distance through the layers of atmosphere resulting in a higher loss of intensity, and lower availability of solar irradiance. To enable the calculation of solar irradiance at any sun angle, the following empirical formula has been proposed in [1] that relates solar irradiance with the air mass. AM I I0 (0.7) (1) where I 0 = 1367 W/m 2 is the solar irradiance in space outside the atmosphere and AM is expressed as 1 AM (2) cos o Z where o is the zenith path length (i.e. normal to the earth's surface) at sea level, Z is the zenith angle and is the path length for the position of the sun at zenith angle Z as shown in Fig. 2. Air mass is more conveniently expressed in terms of the solar altitude angle α, AM sec Z csc (3) where 90, and is given by [1] ( ) sin 1 Z (sin sin cos cos cos) where φ is the latitude, δ is the declination angle and ω is the hour angle. The angle of deviation of the sun from directly above the equator, i.e., 0 latitude, is called the declination angle and can be calculated by the equation given below [1], 360( 80) sin n (5) 365 where n = nth day of the year (i.e. January 1st means n = 1). (4) 75
3 2013 I Conference on ustainable Utilization and Development in ngineering and Technology Outer pace unlight unlight Atmospheric layer o θ θ Z α θ θ arth s urface Figure 2: Distance travelled by the sunlight through the atmospheric layers. In the solar system, the earth undergoes elliptical revolution around the sun in approximately every 365 days and a 360 rotation about its axis once per day. Therefore the position of the sun varies from day to day and from season to season. However the axis of the earth is inclined by an angle of to the plane of the a th s t ajecto y about the sun Because of this inclination the sun tends to be higher in the sky in the summer than in the winter which causes summer to have more sunlight hours and winter to have less sunlight hours. On the first day of summer, the sun positions itself vertically above the Tropic of Cancer, which is latitude north of the equator whereas on the first day of winter, the sun is vertically above the Tropic of Capricorn, which is latitude south of the equator. However on the first day of spring and the first day of fall, the sun is directly above the equator. The hour angle as in solar altitude equation is the number of hours elapsed during the day from sunrise time T sr to time t of the day on a 24-hour clock, expressed in degree and can be calculated as below [1], ( t T ), (6) s 15 sr where ω s is the sunrise angle. From the declination angle and the latitude discussed above, an expression for ω s can be determined as [1], cos 1 s ( tan tan ) (7) B. ffective Area and the Panel Mounting Angle Figure 3 shows how the total radiation received by the panel reduces when incident radiation is not perpendicular on the panel plane. nergy is maximum when incident radiation is perpendicular, for any other angle of incident radiation, the effective area of the panel that receives the energy reduces and so does the received energy. Thus the effective panel area depends on the angle between incident radiation and the normal of the panel plane which varies with the position of the sun and the panel mounting angle. Figure 4 shows the variation in the sun s position in the east-west i ection f o sun ise to sunset If γ is the angula position of the sun at any time of the day and A is the panel area, then the effective area of the panel can be given ffective Area A sinγ (8) (a) Incident Angle 0 o (b) Incident Angle θ o Figure 3: (a) angle of incidence of sunlight and effective area with incidence angle 0 (b) optimization of mounting angle of a fixed collector with incidence angle θ in Ɣ=in 90=1 W Figure 4: Variation in sun s position during the day. Ɣ in Ɣ=in 0=0 At sola noon γ = 90, sunlight falls vertically down and the effective area is equal to the original panel area, provided the panel is mounted flat on the surface. For countries in northern hemisphere such as in Bangladesh, panels are mounted at latitude angle facing south in order to optimize them to receive maximum solar energy for the whole year. With this panel orientation, sunrays fall vertically on panel in spring and fall, however, due to the seasonal variation in sun s inclination, an angle between the normal of the panel and the incident radiation is introduced in the north south direction for other times of the year which reaches its maximum in summer (June 21 st ) and in winter (Dec 21 st ) and thus e uces the panel s effective area, shown in Fig. 5(a). According to this figure, the effective area of the panel for both summer and winter can be given as, A eff A cosδ sin γ (9) m where m is the axi u eviation of sun s position in summer and winter from its position in spring/fall. With a panel ounting angle θ=46 5 the sun ays fall perpendicularly in winter (Dec 21 st ) as shown in Fig. 5b, and the panel will receive maximum energy during winter. However, effective area of the panel is least in summer with this mounting angle. C. Cumulative nergy/olar Irradiation Irradiation quantifies energy density of sunlight that is total energy per square meter per day. It is obtained by integrating total irradiance over daylight hours beginning from sunrise till sunset. If I is the solar irradiance as given by (1) and A eff is the effective area of the panel as given by (9), then the cumulative 76
4 2013 I Conference on ustainable Utilization and Development in ngineering and Technology Mar 21/ep 21 Dec 21 Jun 21 δ m δ m (a) the operational time, it will be on with 2/3rd power for 1/4th of opertaional time, and with 1/3 power for the remaining quarter of operational time, in any given night. Thus the total energy 2 required by the lamps per night with traffic sensor can be calculated by: ( W h) ( W h) ( W h) (13) o θ=23.1 o Mar 21/ep 21 Jun 21 Dec 21 2δ m δ m (b) N IV. CACUATION FOR YTM IZ Figure 6 shows a block diagram of solar powered street light system. The energy collected from the solar panel is stored in the battery through the charge controller during the day. The battery supplies the stored energy to the load at night, through the D driver circuit, which maintains a stable current through the D. All the system components have some internal losses and thereby they do not have 100% efficiency. There is also additional line loss in the electrical wires that connect the different components. 90 o θ= Figure 5: Angular position of the sun with respect to the panel for two different mounting angles (a) θ = 23.1 an (b) θ = 46 5, aligned for two different seasons spring/fall and winter, respectively. energy incident on the panel during a day, expressed in Wh/m 2 /day, is given by, TR Cumulative nergy A eff I dt (10) T where T R and T are the sun rise and sun set times, espectively If η is the efficiency of the panel then the panel output P will be, Cumulative nergy (11) P D. nergy Consumption by the D amp The energy that can be successfully extracted by the solar panel will then be used to power the D lamp at night. For its total operational hours, the total energy 1, consumed by the D lamp per night can be given by 1 W h (12) where W is the rated power of the D lamps and h is the number of hours the light remains on in a given night. With the traffic sensor installed, the lamps can be assumed to operate in full power for half of the operational time with high traffic volume. Traffic volume will decrease after midnight and will reduce significantly in the last quarter of the night. It is understood that there will be occasional increase in traffic volume sometimes late at night. However, the traffic sensor will be smart enough to sense such change and adjust the light intensity accordingly. Therefore, it is reasonable to assume that while the lamps will be on with full power for half N A. Calculation of Battery Capacity As can be seen from Fig. 6, the output of the D driver circuit should be equal to energy required by a D lamp, as calculated according to (12) and (13), for systems without and with traffic sensor, respectively. Considering the losses in the driver circuit, the input to the driver circuit should be D, where D is the efficiency of the driver circuit. The battery needs to supply this energy plus the D line loss with the total amounting to D 1. However, to ensure the supply of energy during the cloudy and rainy days, battery should store more energy than this total energy. The maximum number of days that the battery should be able to drive the load without receiving energy from the source is called days of autonomy which is considered to be 3 days in our calculation. Thus the total energy the battery should be able to supply is given by: T 3 1 D (14) Due to the maximum limit of discharge allowed for a battery as indicated by the depth of discharge (DOD), the capacity of battery has to be even greater. Considering these factors, the maximum energy that should be stored in the battery is given by: 3 1 DOD D (15) The battery capacity in ampere-hour (Ah) can be calculated by dividing by the voltage rating of the battery as shown below: Battery Capacity Ah (16) Battery Voltage 77
5 2013 I Conference on ustainable Utilization and Development in ngineering and Technology p / m 2 (a) θ = 0 olar Panel η D Charge Controller η CC Driver Circuit η D Wh/night Battery Ah, DOD, η B Figure 6: Block diagram of a D based street lighting system showing relevant system parameters. B. Calculation of Panel ize The panel size can now be determined using the total energy required by the D and the cumulative energy output density of the panels, as calculated in the previous sections. The energy that the panel must supply to the battery is T as given by (14) that takes into account the days of autonomy, along with the line loss from panel to battery. This total energy must be divided by the battery efficiency η B that takes into account the losses in the battery during charging and discharging, by the efficiency of the charge controller η CC that takes into account the losses in the charge controller, and by the derating factor, η D, of the panel that results from the loss of panel efficiency due to long time of use, layers of dust and wear etc. Thus the total energy that should be supplied by the panel to the battery, P-B, is given by, PB D CC T 1 B (17) Then the panel size in m 2 can be calculated as, P B Panel ize (18) P Where P is the output energy in Wh of a one meter square panel in one day, calculated according to (11). V. RUT AND DICUION Cumulative energy outputs of panels in Wh/m 2 /day for different seasons for three different mounting angles, = an 46 5 e e calculate using (11) and are shown in Figures 7 (a), (b) and (c), respectively. In the calculation, an efficiency of 16% was assumed for the panels. It is very clear from the Figs.7 (a) and (b) that, while during summer we have the highest energy output exceeding 1000 W/m 2 when we actually need minimum energy to light the lamps, during winter we have the least energy output when we need the maximum energy. Therefore, it is obvious that mounting the panels at an angle that is optimized for spring or summer will not solve the basic challenge faced during winter. In Fig.7c however the scenario is better and well suited to a street lighting system. In winter, we are able to extract maximum energy at a mounting angle of 46.5 compared to those obtained with other mounting angles. Also, with this mounting angle the distribution of solar energy is fairly equal all throughout the year. Cumulative Output nergy (Wh/m 2 /day) pring March 21 st ummer June 21 st Fall ep 21 st (b) θ = 23.1 (c) θ = 46.5 Winter Dec 21 st Figure 7: Cumulative energy output of solar panel in W/m 2 /day in different seasons at three different mounting angles (θ): (a) 0, (b) 23.1 and (c) Figure 8 shows the total energy to be consumed or required by the D lamps to operate during night in different seasons at certain fixed days, calculated using (12) and (13), for systems without (olid line) and with (Dashed line) traffic sensor, respectively. Naturally the latter requires less energy to power the lights as the driver circuit is dependant on the output of a sensor which measures traffic volume. The energy required by the D lamps is proportional to the hours of operation with the energy consumption being the lowest in summer and highest in winter. As the energy requirement is maximum during winter, system size calculated based on the cumulative energy output and energy requirement in winter will also satisfy the requirements of all other seasons. Battery capacity and the panel size were determined for three different mounting angles, = 0 an 46 5 using ( 6) and (18), respectively, for the purpose of comparison. Table I shows the different system parameter values that are used in the calculation of the battery capacity and the panel size. The calculation is based on the cumulative energy output and energy requirement in winter season. 78
6 2013 I Conference on ustainable Utilization and Development in ngineering and Technology Required Watt-Hour per Night Number of Day Figure 8: nergy required to light D lamps per night in different seasons of the year, with (dashed line) and without (solid line) traffic sensor. In Table II, panel size and the battery capacity for the three different mounting angles are tabulated. ooking at the changes with respect to the mounting angles of an 46 5, it can be seen that the panel size is reduced from 3.55 to 3.27 m 2. This shows that about 8.6% reduction in panel size can be brought about by mounting the panel at 46.5, instead of the gene al p actice at. This reduction in size is even greater, about 45% if co pa e to a panel ounte at 0 The battery capacity has no change with respect to varying mounting angles, since it does not depend on the energy collected by the panel in different seasons. Table III shows the panel size and the battery capacity, for the street light system with and without traffic sensor, and percent difference between the corresponding values, calculated for a mounting angle of With traffic sensor, it can be seen that the panel size is reduced from 3.27 to 2.44 m 2, bringing about 34% reduction in panel size. The battery capacity is also reduced similarly by around 33.6%, From to Ah. VI. CONCUION Design of solar powered street light system is complicated by the fact that during summer when we get maximum sunlight, minimum energy is needed to operate the street lights due to shorter summer nights; whereas, during winter when sunlight is minimum, maximum energy is needed due to longer winter nights. In this work, the effect of mounting angle of solar panels and traffic sensing on the requirement of system size for a solar powered street light system is investigated. It has been found that while a mounting angle of 23. hich is well suited to applications like solar home system, yields maximum energy collection in summer and minimum energy collection in winte a ounting angle of 46 5 yields maximum energy collection in winter than those obtained at other mounting angles. Further, more or less uniform energy collection throughout the year is achieved with this mounting angle, which enables the system to be efficient enough to provide full-time operation of load at nights during all seasons of the year. The addition of a traffic sensor ensures that the lamp does not remain lit at its maximum intensity all throughout the night without purpose, thus reducing energy consumption at times of lower traffic volume, and consequently decreasing the system size. Table I: ystem parameter values used in the calculation ystem Parameters Parameter Values Depth of Discharge (DOD) 80% Batte y fficiency (η B ) 80% fficiency of D driver circuit (η D ) fficiency of the charge cont olle ci cuit (η CC ) 95% 95% ine loss ( ) 1% Table II: Panel ize and Battery Capacity for three different mounting angles Mounting Angle Panel ize (m 2 ) Battery Capacity (Ah) Table III: Panel ize and Battery Capacity with and without traffic sensor, and their percentage difference, calculated for a mounting angle of Panel ize (m 2 ) Battery Capacity (Ah) Without Traffic ensor With Traffic ensor %Difference RFRNC [1] Roger A Messenger and Jerry Ventre, Photovoltaic ystems ngineering. 2nd dition. CRC Press C, 2004, pp [2] Meinel, A. B. and Meinel, M. P., Applied olar nergy, an Introduction, Addison-Wesley, Reading, MA, [3] Markvart, T., d., olar lectricity, John Wiley & ons, Chichester, U.K., [4] Arthur David Olson* unrise and unset Ti e in Dhaka Inte net: [Date accessed: 21 October 2012]. [5] hahidul Islam Khan and Md. aifur Rahman. International hort Course on olar Photovoltaic ystem. Dhaka, Bangladesh University of ngineering and Technology, 2010 [6] Reinhard Muller and Andreas Rienar, An nergy fficient Pedestrian Aware mart treet ighting ystem International Journal of Pervasive Computing and Communications, Vol. 7, no. 2, 2011, pp [7] eccese, Fabio, and Zbigniew eonowicz. "Intelligent wireless street lighting system." nvironment and lectrical ngineering (IC), th International Conference on. I, 2012, pp
Exercise 6. Solar Panel Orientation EXERCISE OBJECTIVE DISCUSSION OUTLINE. Introduction to the importance of solar panel orientation DISCUSSION
Exercise 6 Solar Panel Orientation EXERCISE OBJECTIVE When you have completed this exercise, you will understand how the solar illumination at any location on Earth varies over the course of a year. You
More informationME 476 Solar Energy UNIT THREE SOLAR RADIATION
ME 476 Solar Energy UNIT THREE SOLAR RADIATION Unit Outline 2 What is the sun? Radiation from the sun Factors affecting solar radiation Atmospheric effects Solar radiation intensity Air mass Seasonal variations
More informationMotion of the Sun. View Comments
Login 2017 Survey to Improve Photovoltaic Education Christiana Honsberg and Stuart Bowden View Comments Instructions 1. Introduction 2. Properties of Sunlight 2.1. Basics of Light Properties of Light Energy
More informationObserver-Sun Angles. ), Solar altitude angle (α s. ) and solar azimuth angle (γ s )). θ z. = 90 o α s
Observer-Sun Angles Direction of Beam Radiation: The geometric relationships between a plane of any particular orientation relative to the earth at any time and the incoming beam solar radiation can be
More informationEELE408 Photovoltaics Lecture 04: Apparent Motion of the Sum
EELE408 Photovoltaics Lecture 04: Apparent Motion of the um Dr. Todd J. Kaiser tjkaiser@ece.montana.edu Apparent motion of the sun EAT Department of Electrical and Computer Engineering Montana tate University
More informationFLATE Hillsborough Community College - Brandon (813)
The Florida Advanced Technological Education (FLATE) Center wishes to make available, for educational and noncommercial purposes only, materials relevant to the EST1830 Introduction to Alternative/Renewable
More informationSunlight and its Properties Part I. EE 446/646 Y. Baghzouz
Sunlight and its Properties Part I EE 446/646 Y. Baghzouz The Sun a Thermonuclear Furnace The sun is a hot sphere of gas whose internal temperatures reach over 20 million deg. K. Nuclear fusion reaction
More informationPractice Questions: Seasons #1
1. Seasonal changes on Earth are primarily caused by the A) parallelism of the Sun's axis as the Sun revolves around Earth B) changes in distance between Earth and the Sun C) elliptical shape of Earth's
More informationSunlight and its Properties II. EE 446/646 Y. Baghzouz
Sunlight and its Properties II EE 446/646 Y. Baghzouz Solar Time (ST) and Civil (clock) Time (CT) There are two adjustments that need to be made in order to convert ST to CT: The first is the Longitude
More informationPage 1. Name:
Name: 1) What is the primary reason New York State is warmer in July than in February? A) The altitude of the noon Sun is greater in February. B) The insolation in New York is greater in July. C) The Earth
More informationCCMR Educational Programs
CCMR Educational Programs Title: Date Created: August 10, 2006 Latest Revision: August 10, 2006 Author(s): Myriam Ibarra Appropriate Level: Grades 8-10 Abstract: Energy and the Angle of Insolation Sun
More informationPractice Seasons Moon Quiz
1. Which diagram represents the tilt of Earth's axis relative to the Sun's rays on December 15? A) B) C) D) 2. The diagram below represents Earth in space on the first day of a season. 5. Base your answer
More information4. Solar radiation on tilted surfaces
4. Solar radiation on tilted surfaces Petros Axaopoulos TEI of Athens Greece Learning Outcomes After studying this chapter, readers will be able to: define the direct, diffuse and reflected solar radiation
More informationNovember 20, NOTES ES Rotation, Rev, Tilt.notebook. vertically. night. night. counterclockwise. counterclockwise. East. Foucault.
NOTES ES, Rev,.notebook, and Rotates on an imaginary axis that runs from the to the South North Pole Pole vertically North The of the axis points to a point in space near day Pole Polaris night Responsible
More informationChapter 2. Heating Earth's Surface & Atmosphere
Chapter 2 Heating Earth's Surface & Atmosphere Topics Earth-Sun Relationships Energy, Heat and Temperature Mechanisms of Heat Transfer What happens to Incoming Solar Radiation? Radiation Emitted by the
More informationCOMPUTER PROGRAM FOR THE ANGLES DESCRIBING THE SUN S APPARENT MOVEMENT IN THE SKY
COMPUTER PROGRAM FOR THE ANGLES DESCRIBING THE SUN S APPARENT MOVEMENT IN THE SKY B. BUTUC 1 Gh. MOLDOVEAN 1 Abstract: The paper presents software developed for the determination of the Sun-Earth geometry.
More information1. The frequency of an electromagnetic wave is proportional to its wavelength. a. directly *b. inversely
CHAPTER 3 SOLAR AND TERRESTRIAL RADIATION MULTIPLE CHOICE QUESTIONS 1. The frequency of an electromagnetic wave is proportional to its wavelength. a. directly *b. inversely 2. is the distance between successive
More informationChapter 6. Solar Geometry. Contents
Chapter 6. Solar Geometry Contents 6.1 Introduction 6.2 The Sun 6.3 Elliptical Orbit 6.4 Tilt of the Earth s Axis 6.5 Consequences of the Altitude Angle 6.6 Winter 6.7 The Sun Revolves Around the Earth!
More informationEarth s Orbit. Sun Earth Relationships Ridha Hamidi, Ph.D. ESCI-61 Introduction to Photovoltaic Technology
1 ESCI-61 Introduction to Photovoltaic Technology Sun Earth Relationships Ridha Hamidi, Ph.D. Spring (sun aims directly at equator) Winter (northern hemisphere 23.5 tilts away from sun) 2 Solar radiation
More informationEGEE 437: HWK #2. Brownson. Yaqdaan Alkayyoomi, Mackenzie Ailes, Nicholas Minutillo, Sheel Vora. Group 17. Due on Thursday, Feb.
EGEE 437: HWK #2 Group 17 Due on Thursday, Feb. 18, 2016 Brownson Yaqdaan Alkayyoomi, Mackenzie Ailes, Nicholas Minutillo, Sheel Vora Contents Problem 5.1............................................ 2
More informationC) wavelength C) eastern horizon B) the angle of insolation is high B) increases, only D) thermosphere D) receive low-angle insolation
1. What is the basic difference between ultraviolet, visible, and infrared radiation? A) half-life B) temperature C) wavelength D) wave velocity 2. In New York State, the risk of sunburn is greatest between
More informationExploration Phase What are the differences between these pictures?
Light Power and seasons Exploration Phase What are the differences between these pictures? 1 Lab Activity: Lab Activity Obtain a Styrofoam ball. This will represent the earth. Stick a push pin into the
More informationThe Sun. Fabio Peron Università IUAV - Venezia. Earth-Sun relationships. The Sun. Photosphere (Emits much of the solar radiant power)
Università IUAV Venezia Corso di Fisica Tecnica Ambientale Laboratorio Integrato Innovazione-Sostenibilità Sun and solar radiation Fabio Peron Università IUAV - Venezia The Sun The Sun Earth-Sun relationships
More informationSolar Time, Angles, and Irradiance Calculator: User Manual
Solar Time, Angles, and Irradiance Calculator: User Manual Circular 674 Thomas Jenkins and Gabriel Bolivar-Mendoza 1 Cooperative Extension Service Engineering New Mexico Resource Network College of Agricultural,
More informationHeat Transfer. Energy from the Sun. Introduction
Heat Transfer Energy from the Sun Introduction The sun rises in the east and sets in the west, but its exact path changes over the course of the year, which causes the seasons. In order to use the sun
More informationPhotovoltaic Systems Engineering
Photovoltaic Systems Engineering Ali Karimpour Associate Professor Ferdowsi University of Mashhad Reference for this lecture: Photovoltaic Systems Engineering Third Edition CRC Roger Messenger, Jerry Ventre
More informationC) the seasonal changes in constellations viewed in the night sky D) The duration of insolation will increase and the temperature will increase.
1. Which event is a direct result of Earth's revolution? A) the apparent deflection of winds B) the changing of the Moon phases C) the seasonal changes in constellations viewed in the night sky D) the
More informationFor most observers on Earth, the sun rises in the eastern
632 CHAPTER 25: EARTH, SUN, AND SEASONS WHAT IS THE SUN S APPARENT PATH ACROSS THE SKY? For most observers on Earth, the sun rises in the eastern part of the sky. The sun reaches its greatest angular altitude
More informationChapter 2 Available Solar Radiation
Chapter 2 Available Solar Radiation DEFINITIONS Figure shows the primary radiation fluxes on a surface at or near the ground that are important in connection with solar thermal processes. DEFINITIONS It
More informationEE Properties of Sunlight. Y. Baghzouz Professor of Electrical Engineering
EE 495-695 2.2 Properties of Sunlight Y. Baghzouz Professor of Electrical Engineering Azimuth angle The azimuth angle is the compass direction from which the sunlight is coming. At the equinoxes, the sun
More informationSun or Moon Rise/Set Table for One Year
1.4l interpret charts and diagrams showing the variation in daylight length during a year 1.4m demonstrate an understanding that there are seasonal variations in the rising and setting of the un Daylight
More informationHEATING THE ATMOSPHERE
HEATING THE ATMOSPHERE Earth and Sun 99.9% of Earth s heat comes from Sun But
More informationWhich graph best shows the relationship between intensity of insolation and position on the Earth's surface? A) B) C) D)
1. The hottest climates on Earth are located near the Equator because this region A) is usually closest to the Sun B) reflects the greatest amount of insolation C) receives the most hours of daylight D)
More informationCOMPOSITION OF ALTERNATIVE ENERGY BATTERY CHARGING STATION
COMPOITIO OF ALTRATIV RGY BATTRY CHARGIG TATIO Janis Laceklis-Bertmanis, Uldis Putnieks, Janis Mistris, Maris Gailis, Liene Kancevica Latvia University of Agriculture janis.laceklis@llu.lv, uldis.putnieks@llu.lv,
More informationEarth Motions Packet 14
Earth Motions Packet 14 Your Name Group Members Score Minutes Standard 4 Key Idea 1 Performance Indicator 1.1 Explain complex phenomena, such as tides, variations in day length, solar insolation, apparent
More informationL.O: THE ANGLE OF INSOLATION ANGLE INSOLATION: THE ANGLE SUNLIGHT HITS THE EARTH
L.O: THE ANGLE OF INSOLATION ANGLE INSOLATION: THE ANGLE SUNLIGHT HITS THE EARTH 1. The graph below shows air temperatures on a clear summer day from 7 a.m. to 12 noon at two locations, one in Florida
More informationChapter 1 Solar Radiation
Chapter 1 Solar Radiation THE SUN The sun is a sphere of intensely hot gaseous matter with a diameter of 1.39 10 9 m It is, on the average, 1.5 10 11 m away from the earth. The sun rotates on its axis
More informationGeography Class 6 Chapters 3 and
CHAPTER 3 MOTIONS OF THE EARTH The Earth is always travelling in Space. That makes each person on Earth, a Space Traveller. No one feels the movement of the Earth because humans are too tiny when compared
More informationPhotovoltaic Systems Solar Radiation
PowerPoint Presentation Photovoltaic Systems Solar Radiation The Sun Solar Radiation Sun- Earth Relationships Array Orientation Solar Radiation Data Sets Estimating Array Performance Arizona Solar Power
More informationcore temperature: more than surface Definition of revolution How long it takes Earth to make one revolution around the Sun
Lesson 1 Earth s Motion kim Lesson 1 in your book. Read the headings and look at the photos and illustrations. Write three things you want to learn more about as you read the lesson. Write your ideas in
More informationOptimizing the Photovoltaic Solar Energy Capture on Sunny and Cloudy Days Using a Solar Tracking System
Optimizing the Photovoltaic Solar Energy Capture on Sunny and Cloudy Days Using a Solar Tracking System Nelson A. Kelly and Thomas L. Gibson Chemical Sciences and Material Systems Laboratory General Motors
More informationThe Sun-Earth-Moon System
CHAPTER 20 The un-earth-moon ystem LEO 1 Earth s Motion What do you think? Read the two statements below and decide whether you agree or disagree with them. Place an A in the Before column if you agree
More informationLECTURE ONE The Astronomy of Climate
LECTURE ONE The Astronomy of Climate Agricultural Science Climatology Semester 2, 2006 Richard Thompson http://www.physics.usyd.edu.au/ag/agschome.htm Course Coordinator: Mike Wheatland AMMENDED TIMETABLE
More informationCartesian Coordinates Need two dimensional system 2 number lines perpendicular to each other X-axis is horizontal Y-axis is vertical Position relative
General Physical Science Chapter 15 Place and Time Space and Time Einstein Space and time related Single entity Time is the 4 th dimension! Cartesian Coordinates Need some system to tell us where something
More informationChapter 11 Lecture Outline. Heating the Atmosphere
Chapter 11 Lecture Outline Heating the Atmosphere They are still here! Focus on the Atmosphere Weather Occurs over a short period of time Constantly changing Climate Averaged over a long period of time
More informationThe Motion of the Sun in Different Locations
ame: Partner(s): 1101 or 3310: Desk # Date: Purpose The Motion of the Sun in Different Locations Describe the path of the Sun in the sky as seen from the equator of the Earth Describe the path of the Sun
More informationAgricultural Science Climatology Semester 2, Anne Green / Richard Thompson
Agricultural Science Climatology Semester 2, 2006 Anne Green / Richard Thompson http://www.physics.usyd.edu.au/ag/agschome.htm Course Coordinator: Mike Wheatland Course Goals Evaluate & interpret information,
More informationIntroduction to Photovoltaics
INTRODUCTION Objectives Understand the photovoltaic effect. Understand the properties of light. Describe frequency and wavelength. Understand the factors that determine available light energy. Use software
More informationSOLAR WATER HEATER WITH TRACKING SYSTEM
SOLAR WATER HEATER WITH TRACKING SYSTEM Jyoti Verma 1, Shweta Tyagi 2, R. B. Dubey 3 1,2,3 Department of Electronics and Communication Engineering Hindu College of Engineering, Sonepat, Haryana, (India)
More informationMeteorology Pretest on Chapter 2
Meteorology Pretest on Chapter 2 MULTIPLE CHOICE 1. The earth emits terrestrial radiation a) only at night b) all the time c) only during winter d) only over the continents 2. If an imbalance occurs between
More informationLESSON PLAN - Optimum Orientation of Solar Panels Using Soltrex Data
LESSON PLAN - Optimum Orientation of Solar Panels Using Soltrex Data Title of Lesson: Optimum Orientation of Solar Panels Using Soltrex Data Description of class: High School physics, astronomy, or environmental
More informationLecture #03. January 20, 2010, Wednesday
Lecture #03 January 20, 2010, Wednesday Causes of Earth s Seasons Earth-Sun geometry Day length Solar angle (beam spread) Atmospheric beam depletion Shape and Size of the Earth North Pole E Geoid: not
More informationOPTIMIZATION OF GLOBAL SOLAR RADIATION OF TILT ANGLE FOR SOLAR PANELS, LOCATION: OUARGLA, ALGERIA
OPTIMIZATION OF GLOBAL SOLAR RADIATION OF TILT ANGLE FOR SOLAR PANELS, LOCATION: OUARGLA, ALGERIA Mohamed Lakhdar LOUAZENE Dris KORICHI Department of Electrical Engineering, University of Ouargla, Algeria.
More informationBasic information about developed Calculator for solar / wind hybrid power supply
Basic information about developed Calculator for solar / wind hybrid power supply It simulates behavior of the system for off grid power supply (components: solar panels, wind generator, batteries and
More informationEarth is rotating on its own axis
Earth is rotating on its own axis 1 rotation every day (24 hours) Earth is rotating counterclockwise if you are looking at its North pole from other space. Earth is rotating clockwise if you are looking
More informationSURFACE ORIENTATIONS AND ENERGY POLICY FOR SOLAR MODULE APPLICATIONS IN DHAKA, BANGLADESH
International Journal of Scientific & Engineering Research, Volume 5, Issue, February-014 83 ISSN 9-5518 SURFACE ORIENTATIONS AND ENERGY POLICY FOR SOLAR MODULE APPLICATIONS IN DHAKA, BANGLADESH 1 Debazit
More informationdrinking straw, protractor, string, and rock. observer on Earth. Sun across the sky on March 21 as seen by an
1. The diagram below represents some constellations and one position of Earth in its orbit around the Sun. These constellations are visible to an observer on Earth at different times of the year. When
More informationSeasons. What causes the seasons?
Questions: Seasons What causes the seasons? How do we mark the progression of the seasons? What is the seasonal motion of the sun in the sky? What could cause the seasonal motion of the sun to change over
More informationL.O: EARTH'S 23.5 DEGREE TILT ON ITS AXIS GIVES EARTH ITS SEASONS March 21 (SPRING), June 21(SUMMER), Sept 22 (AUTUMN) & Dec 21(WINTER)
L.O: EARTH'S 23.5 DEGREE TILT ON ITS AXIS GIVES EARTH ITS SEASONS March 21 (SPRING), June 21(SUMMER), Sept 22 (AUTUMN) & Dec 21(WINTER) 1. The apparent daily path of the Sun changes with the seasons because
More informationLAB: What Events Mark the Beginning of Each Season?
Name: Date: LAB: What Events Mark the Beginning of Each Season? The relationship between the Sun and Earth have been used since antiquity to measure time. The day is measured by the passage of the Sun
More informationChapter S1 Celestial Timekeeping and Navigation. How do we define the day, month, year, and planetary time periods?
Chapter S1 Celestial Timekeeping and Navigation S1.1 Astronomical Time Periods Our goals for learning:! How do we define the day, month, year, and planetary time periods?! How do we tell the time of day?!
More informationChapter Seven. Solar Energy
Chapter Seven Solar Energy Why Studying Solar energy To know the heat gain or heat loss in a building In making energy studies In the design of solar passive homes. Thermal Radiation Solar spectrum is
More informationNATS 101 Section 13: Lecture 7. The Seasons
NATS 101 Section 13: Lecture 7 The Seasons The Importance of Seasons The seasons govern both natural and human patterns of behavior. Some big and small examples: Planting and harvesting of crops Migratory
More informationLecture 2: Global Energy Cycle
Lecture 2: Global Energy Cycle Planetary energy balance Greenhouse Effect Vertical energy balance Solar Flux and Flux Density Solar Luminosity (L) the constant flux of energy put out by the sun L = 3.9
More informationThe following terms are some of the vocabulary that students should be familiar with in order to fully master this lesson.
Lesson 211: EARTH'S SEASONS Students learn the complex geometry and planetary motions that cause Earth to have four distinct seasons. Fundamental Questions Attempting to give thorough and reasonable answers
More informationBi-annual Sun Tracking for Solar PV Module Support Structure: Study and Implementation
16th NATIONAL POWER SYSTEMS CONFERENCE, 15th-17th DECEMBER, 2010 56 Bi-annual Sun Tracking for Solar PV Module Support Structure: Study and Implementation Prabodh Bajpai, Member IEEE, Vaishalee Dash, N.K.
More informationThe Earth is a Rotating Sphere
The Earth is a Rotating Sphere The Shape of the Earth Earth s Rotation ( and relative movement of the Sun and Moon) The Geographic Grid Map Projections Global Time The Earth s Revolution around the Sun
More informationSolar Radiation Measurements and Model Calculations at Inclined Surfaces
Solar Radiation Measurements and Model Calculations at Inclined Surfaces Kazadzis S. 1*, Raptis I.P. 1, V. Psiloglou 1, Kazantzidis A. 2, Bais A. 3 1 Institute for Environmental Research and Sustainable
More informationEarth is tilted (oblique) on its Axis!
MONDAY AM Radiation, Atmospheric Greenhouse Effect Earth's orbit around the Sun is slightly elliptical (not circular) Seasons & Days Why do we have seasons? Why aren't seasonal temperatures highest at
More informationSeasons & Time.
Seasons & Time Earth s Movements Rotation Movement of Earth Around the Sun Elliptical Orbit Revolution 24 Hours (1 Day) 365 Days (1 Year) The Earth s Revolution & the Tilt of the axis cause variations
More informationAileen A. O Donoghue Priest Associate Professor of Physics
SOAR: The Sky in Motion Life on the Tilted Teacup Ride The Year Aileen A. O Donoghue Priest Associate Professor of Physics Celestial Coordinates Right Ascension RA or From prime meridian (0 h ) to 23 h
More informationSeasons ASTR 101 2/12/2018
Seasons ASTR 101 2/12/2018 1 What causes the seasons? Perihelion: closest to Sun around January 4 th Northern Summer Southern Winter 147 million km 152 million km Aphelion (farthest to Sun) around July
More information3. The Sun s Position
3. The Sun s Position In order to understand how to collect energy from the sun, one must first be able to predict the location of the sun relative to the collection device. In this chapter we develop
More informationWhich Earth latitude receives the greatest intensity of insolation when Earth is at the position shown in the diagram? A) 0 B) 23 N C) 55 N D) 90 N
1. In which list are the forms of electromagnetic energy arranged in order from longest to shortest wavelengths? A) gamma rays, x-rays, ultraviolet rays, visible light B) radio waves, infrared rays, visible
More informationDesign and implementation of a sensorless dual axis solar tracking system based on solar sun chart algorithm using arduino
Design and implementation of a sensorless dual axis solar tracking system based on solar sun chart algorithm using arduino Fazlur Rahman Bin Karim, Md. Mamunor Rashed, Muhammad Quamruzzaman Department
More informationSolar photovoltaic energy production comparison of east, west, south-facing and tracked arrays
The Canadian Society for Bioengineering The Canadian society for engineering in agricultural, food, environmental, and biological systems. La Société Canadienne de Génie Agroalimentaire et de Bioingénierie
More informationSUBJECT : GEOGRAPHY ROTATION AND REVOLUTION This paper consists of 5 printed pages.
SUBJECT : GEOGRAPHY ROTATION AND REVOLUTION 2017-2018 This paper consists of 5 printed pages. 1. Name the motions of the earth. A. They are Rotation and Revolution. 2. What is Rotation? A. Rotation is
More informationTools of Astronomy Tools of Astronomy
Tools of Astronomy Tools of Astronomy The light that comes to Earth from distant objects is the best tool that astronomers can use to learn about the universe. In most cases, there is no other way to study
More informationStudent Exploration: Seasons: Earth, Moon, and Sun
Name: Date: Student Exploration: Seasons: Earth, Moon, and Sun Vocabulary: altitude, axis, azimuth, equinox, horizon, latitude, revolution, rotation, solstice Prior Knowledge Questions (Do these BEFORE
More informationSeasonal & Daily Temperatures
Seasonal & Daily Temperatures Photo MER Variations in energy input control seasonal and daily temperature fluctuations 1 Cause of the Seasons The tilt of the Earth s axis relative to the plane of its orbit
More informationEarth-Sun Relationships. The Reasons for the Seasons
Earth-Sun Relationships The Reasons for the Seasons Solar Radiation The earth intercepts less than one two-billionth of the energy given off by the sun. However, the radiation is sufficient to provide
More informationReasons for the seasons - Rebecca Kaplan
Reasons for the seasons - Rebecca Kaplan https://www.youtube.com/watch?v=dd_8jm5ptlk https://www.timeanddate.com/worldclock/sunearth.html https://www.time.gov/ https://www.space.com/33790-harvest-moon-guide.html
More informationEstimation of Hourly Solar Radiation on Horizontal and Inclined Surfaces in Western Himalayas
Smart Grid and Renewable Energy, 2011, 2, 45-55 doi:10.4236/sgre.2011.21006 Published Online February 2011 (http://www.scirp.org/journal/sgre) 45 Estimation of Hourly Solar Radiation on Horizontal and
More informationMarch 21. Observer located at 42 N. Horizon
March 21 Sun Observer located at 42 N Horizon 48 June 21 March 21 A 48 90 S 23.5 S 0 23.5 N 42 N 90 N Equator (June 21) C (March 21) B A 71.5 48 Horizon 24.5 Observer Sun 40 Observer Sun 22 Observer Sun
More information(1) Over the course of a day, the sun angle at any particular place varies. Why?
(1) Over the course of a day, the sun angle at any particular place varies. Why? (Note: Although all responses below are true statements, only one of them actually explains the observation!) (A)The sun
More informationSolar Insolation and Earth Radiation Budget Measurements
Week 13: November 19-23 Solar Insolation and Earth Radiation Budget Measurements Topics: 1. Daily solar insolation calculations 2. Orbital variations effect on insolation 3. Total solar irradiance measurements
More informationNABCEP Entry Level Exam Review Solfest practice test by Sean White
1. A fall protection system must be in place for all work done at heights in excess of a. 4 feet b. 6 feet c. 8 feet d. 10 feet 2. A circuit breaker performs the same function a. as a fuse b. as a switch
More informationMIDTERM REVIEW QUESTIONS - PACKET #2 (75 MULTIPLE CHOICE QUESTIONS)
MIDTERM REVIEW QUESTIONS - PACKET #2 (75 MULTIPLE CHOICE QUESTIONS) 1. Which graph best represents the effect that heating has on air density in the atmosphere? 2. An empty 250-milliliter beaker has a
More informationDIRECTING SUN PANELS
sunpan, April 9, 2015 1 DIRECTING SUN PANELS GERRIT DRAISMA 1. Introduction The quantity of sun light captured by sun panels depends on intensity and direction of solar radiation, area of the panels, and
More informationSeasonal & Diurnal Temp Variations. Earth-Sun Distance. Eccentricity 2/2/2010. ATS351 Lecture 3
Seasonal & Diurnal Temp Variations ATS351 Lecture 3 Earth-Sun Distance Change in distance has only a minimal effect on seasonal temperature. Note that during the N. hemisphere winter, we are CLOSER to
More informationPhysics 312 Introduction to Astrophysics Lecture 3
Physics 312 Introduction to Astrophysics Lecture 3 James Buckley buckley@wuphys.wustl.edu Lecture 3 Celestial Coordinates the Planets and more History Reason for the Seasons Summer Solstice: Northern Hemisphere
More information9/1/14. Chapter 2: Heating Earth s Surface and Atmosphere. The Atmosphere: An Introduction to Meteorology, 12 th. Lutgens Tarbuck
Chapter 2: Heating Earth s Surface and Atmosphere The Atmosphere: An Introduction to Meteorology, 12 th Lutgens Tarbuck Lectures by: Heather Gallacher, Cleveland State University! Earth s two principal
More informationGreen Computing. A study to measure the Accuracy of ATmega 32 MCU in solving the complicated astronomical equation Ahmed J. Abid
Green Computing A study to measure the Accuracy of ATmega 32 MCU in solving the complicated astronomical equation Ahmed J. Abid Electronic Engineering Department Foundation of Technical Education, Baghdad,
More informationTHE EARTH AND ITS REPRESENTATION
UNIT 7 THE EARTH AND ITS REPRESENTATION TABLE OF CONTENTS 1 THE EARTH AND THE SOLAR SYSTEM... 2 2 THE EARTH S MOVEMENTS... 2 2.1 Rotation.... 2 2.2 The revolution of the Earth: seasons of the year....
More informationBasic Solar Geometry. Contents
Basic Solar Geometry Soteris A. Kalogirou Cyprus University of Technology Limassol, Cyprus Contents Introduction The sun (general characteristics) Solar geometry Solar Geometry Reckoning of time (AST)
More information3. The diagram below shows the Moon at four positions in its orbit around Earth as viewed from above the North Pole.
1. Which object orbits Earth in both the Earth-centered (geocentric) and Sun-centered (heliocentric) models of our solar system? (1) Polaris (3) the Sun (2) Venus (4) the Moon 2. A cycle of Moon phases
More informationEarth Moon Motions A B1
Earth Moon Motions A B1 1. The Coriolis effect provides evidence that Earth (1) rotates on its axis (2) revolves around the Sun (3) undergoes cyclic tidal changes (4) has a slightly eccentric orbit 9.
More informationAim: What causes Seasons?
Notepack 28 Aim: What causes Seasons? Do Now: What is the difference between revolution and rotation? Earth s rotation The Earth rotates on its axis (imaginary vertical line around which Earth spins) every
More informationLiterature Review: 1.
Literature Review: 1. The Solar Tracker, a device that keeps photovoltaic or photo-thermal panels in an optimum position perpendicularly to the solar radiation during daylight hours, can increase the collected
More informationMotions of the Sun Model Exploration
Name Date Bell Motions of the Sun Model Exploration 1. Go to the University of Nebraska-Lincoln Motions of the Sun Simulator: http://astro.unl.edu/naap/motion3/animations/sunmotions.swf 2. This is what
More information