聚光型太陽電池發展趨勢(OE_10290)

陳怡嘉yjchen@mail.ndhu.edu.tw

國立東華大學光電工程學系

2015-03-13 (Friday)14:10-17:00

(Contents are solely for educational purpose)

1. 能源需求2. 太陽光

1.太陽能2.單位換算3.太陽光譜4.空氣質量

3. 太陽能電池4. 聚光型太陽能電池

http://www.businessinsider.com.au/human-energy-consumption-moves-beyond-500-exajoules-2012-2

Global Primary Energy Consumption

Individual

Accumulated

2015 2020 2025

In 2008, total worldwide energy consumption was 474 exajoules (132,000 TWh). This is equivalent to an average power use of 15 terawatts (2.0×1010 hp).[1] Based upon some attempted estimates, making strong assumptions, the annual potential for renewable energy are of the order of:

• solar energy 1,575 EJ (438,000 TWh),• wind power 640 EJ (180,000 TWh),• geothermal energy 5,000 EJ (1,400,000 TWh),• biomass 276 EJ (77,000 TWh),• hydropower 50 EJ (14,000 TWh) and• ocean energy 1 EJ (280 TWh).[2][3][4]

http://en.wikipedia.org/wiki/World_energy_consumption

"Consumption by fuel, 1965–2008" (XLS). Statistical Review of World Energy 2009. BP. 8 June 2009. Archived from the original on 26 July 2013. Retrieved 24 October 2009.

World Energy Assessment (WEA). UNDP, New York

Johansson, T. B., McCormick, K., Neij, L., & Turkenburg, W. (2004). The Potentials of Renewable Energy: Thematic Background Paper. Thematic Paper prepared for the International Conference on Renewable Energies, Bonn. Retrieved 6 July 2008, from http://www.iiiee.lu.se/C1256B88002B16EB/$webAll/02DAE4E6199783A9C1256E29004E1250?OpenDocumentde Vries BJM, van Vuuren DP, Hoogwijk MM (2007). "Renewable energy sources: Their global potential for the first-half of the 21st century at a global level: An integrated approach". Energy Policy 35: 2590–2610. doi:10.1016/j.enpol.2006.09.002

[1]

[2]

[3]

[4]

Global Primary Energy Consumption

Unit Conversion

TWhEJ 000,132474 How?

hourh

secondJouleW

JouleJ

T

E

:

/:

:

10:

10:12

18

J

minute

second

h

minuteh

second

Jh

second

JWh 36006060111

Energy

Conversion between energy and power

Value of energy in TWh can be obtained by multiplying value of energy in EJ

by .

12

18

10

10

3600

1

3600

12

18

10

10

3600

1

TWEJ 15474

Why? Explained later.

Value of equivalent power in TW can be obtained by multiplying the

corresponding value of energy in EJ by .474

15

How?

Consumption of electric energy is measured in watt-hours (written W·h, equal to Watt x Hour)1 W·h = 3600 joule = 859.8 calorie.

Electric and electronic devices consume electric energy to generate desired output (i.e. light, heat, motion, etc.). During operation, some part of the energy is consumed in unintended output, such as waste heat. See Electrical Efficiency .

In 2008, the world total of electricity production and consumption was 20,279 TWh (terawatt-hours). This number corresponds to an average consumption rate of around 2.3 terawatts continuously during the year. The total energy needed to produce this power is roughly a factor 2 to 3 higher because the efficiency of power plants is roughly 30-50%, see Electricity generation. The generated power is thus in the order of 5 TW. This is approximately a third of the total energy consumption of 15 TW, see World energy consumption.

16816TWh (83%) of electric energy was consumed by final users. The difference of 3464TWh (17%) was consumed in the process of generating power and consumed as transmission loss and all most consumed at misuse.

Electric Energy Consumption

http://en.wikipedia.org/wiki/Electric_energy_consumption

Total worldwide energy consumption TWh000,132

World total of electricity consumption TWh279,20

Electric energy consumed by final users TWh816,16

Energy needed to produce the world total of electricity consumption

TWh089,46

(Efficiency of power plants is roughly 30-50%, say, 44%)

Global and Electric Energy Consumptions

3

1~

2

1~

%83~

(The difference of 3464 TWh (17%) was consumed in the process of generating power and consumed as transmission loss and all most consumed at misuse.)

%44

1279,20 TWh

1. 能源需求2. 太陽光

1.太陽能2.單位換算3.太陽光譜4.空氣質量

3. 太陽能電池4. 聚光型太陽能電池

PW = 1015 W

http://earsi.com/ggp01.htm

(1 PW = 1,000,000,000,000,000 Watts)petawatts (PW)

Global Solar Energy Flows

SI multiples for watt (W)

Submultiples Multiples

Value Symbol Name Value Symbol Name

10−1 W dW deciwatt 101 W daW decawatt

10−2 W cW centiwatt 102 W hW hectowatt

10−3 W mW milliwatt 103 W kW kilowatt

10−6 W µW microwatt 106 W MW megawatt

10−9 W nW nanowatt 109 W GW gigawatt

10−12 W pW picowatt 1012 W TW terawatt

10−15 W fW femtowatt 1015 W PW petawatt10−18 W aW attowatt 1018 W EW exawatt

10−21 W zW zeptowatt 1021 W ZW zettawatt

10−24 W yW yoctowatt 1024 W YW yottawatt

Common multiples are in bold face

Standard SI Prefixes for Watt

Outstanding solar potential compared to all other energy sources

http://upload.wikimedia.org/wikipedia/commons/b/b6/Global_energy_potential_perez_2009_en.svg

http://en.wikipedia.org/wiki/Solar_energy

Compared with 174 PW (174,000 TW) of total incoming solar radiation

Yearly Solar fluxes & Human Energy Consumption

Solar 3,850,000 EJ

Wind 2,250 EJ

Biomass potential 100–300 EJ

Primary energy use (2010) 539 EJ

Electricity (2010) 66.5 EJ

EJ = 1018 J

http://en.wikipedia.org/wiki/Solar_energy

Yearly Solar Fluxes & Human Energy Consumption

Equivalent to non-reflected solar power of 122 PW

Energy FluxPower

174 PW

EJJoules

sshrsdaysPW

264,487,510487.5

sec60min602436517424

Total incoming solar radiation 174 PW

Reflected radiation 52 PW

EJJoules

sshrsdaysPW

872,639,110487.5

sec60min60243655224

Non-reflected radiation 174 – 52 = 122 PW

EJEJEJEJ 000,850,3392,847,3872,639,1264,487,5

5,487,264 EJ/yr 1367 W/m2

3,850,000 EJ/yr122 PW 957 W/m2

Total

Non-reflected

Equivalence of Solar Fluxes

Area of cross section of earth sphere passing through sphere center= r2 = (40000 / 2 / )2 = 1.2732 108 km2

Circumference of earth sphere 40000 km ( = D)

Irradiance (power flux) normal to the sun radiation

22223

15

8287.1361367

)10(

10

1027.1

174

1027.1

174

halfinglobeofsectioncrossofArea

radiationsolarincomingTotal

cm

mW

m

W

m

W

km

PW

Energy FluxPower

174 PW 5,487,264 EJ/yr 1367 W/m2

3,850,000 EJ/yr122 PW 957 W/m2

Total

Non-reflected

Equivalence of Solar Fluxes

http://facweb.bhc.edu/academics/science/harwoodr/GEOG101/Study/LongLat.htm

Radius 6378.1 km (equatorial) 6356.8 km (polar)

Circumference 40075.017 km (equatorial) 40007.860 km (meridional) 

Surface area 510072000 km2

http://en.wikipedia.org/wiki/Earth

Earth Dimensions

400 km377 km

23 km

Energy (EJ) Energy (TWh)Power

174,000 TW 5,487,264 EJ/yr 1,530,000,000 TWh/yr

474 EJ/yr15 TW 132,000 TWh/yr

Solar Energy

Global Energy consumption

Equivalence of Solar Fluxes

1. 能源需求2. 太陽光

1.太陽能2.單位換算3.太陽光譜4.空氣質量

3. 太陽能電池4. 聚光型太陽能電池

1KLOE=4032度

Joule, 1 J = 1 N × 1 m

joule = volt × coulomb

( 一 )1 卡 (Cal) ＝ 4.1868焦耳 (Joule)

( 二 )1BTU ＝ 1,055焦耳 (Joule) ＝ 252 卡 (Cal)

( 三 )1千瓦小時 (kWh) ＝ 3.6×106 焦耳

( 四 )1千公秉油當量 (KLOE，相當於 1千公秉原油所含之熱量 ) ＝ 9.0百萬千卡＝ 9.2×106 Kcal ＝ 9.2×109 Cal

( 五 )1千公噸標準煤當量 (KTCE，相當於 1千公噸標準煤所含的熱量 ) ＝ 6.4百萬千卡＝ 6.4×106 Kcal ＝ 6.4×109 Cal

( 六 )1公噸油當量 (TOE，相當於 1公噸原油所含之熱量 ) ＝ 1千萬千卡＝ 1.0×107 Kcal ＝ 1.0×1010 Cal ＝ 4.1868×1010 焦耳 (Joule)

常用的能量單位包括：•英國熱能單位 (Btu)：1個英國熱能單位等於將 1磅的水溫度升高 1華氏度所需要的熱量。它是用來計量燃料能量和產熱設備輸出功率的標準度量單位。•卡路里 (Cal)：1卡路里等於將 1克水溫度升高 1攝氏度所需要的能量。•焦耳 (J)：能量計量的基本單位。 1焦耳定義為使用 1牛頓力使物體沿力的方向移動 1米所消耗的能量。•千瓦小時 (kWh)：千瓦小時一般用來度量一段時間內電能的消耗量。用這個單位可以有效地計量家用電器（比如電冰箱）的耗電量。每月的電費帳單也是採用千瓦小時來計量的。 1千瓦等於 1000瓦， 1千瓦小時就是一個功率為 1000瓦的用電設備 1小時的耗電量。•噸油當量：1噸油當量表示燃燒一噸（ 1000公斤）或者 7.4桶石油所獲得的能量。 1噸油當量等價於 1270立方米天然氣或者 1.4噸煤所蘊藏的能量，即 41.87千兆焦耳（ GJ）或者 11.63兆瓦時能量。

http://www.energyland.emsd.gov.hk/tc/energy/principle/measuring.html

初級能源的能量值  

煤 - 約 250萬英國熱能單位／噸原油 - 約 560萬英國熱能單位／桶油 - 約 578萬英國熱能單位／桶天然氣 - 約 1,030英國熱能單位／立方尺液態天然氣 - 約 250萬英國熱能單位／桶   

http://www.energyland.emsd.gov.hk/tc/energy/principle/measuring.html

功率的度量功率是指能量消耗的速度。功率的度量單位有馬力和瓦特。和能量的單位一樣，功率的單位也可以相互轉換。•馬力：馬力是功的單位。這個單位最初用來度量將煤從煤礦中提升上來所需要的能量。為了更好的理解馬力這個單位，可以做如下的換算，即 1馬力等於將33000磅的物體在 1分鐘內提升 1英尺所做的功。•瓦特：瓦特是功率的單位，表示在特定的時間內，能源消耗的速度。 1瓦特等於每秒 1焦耳。

http://www.energyland.emsd.gov.hk/tc/energy/principle/measuring.html

能量單位換算  

1 卡路里 = 4.1868 焦耳1 英國熱能單位 = 1,055 焦耳

= 252 卡路里1 千瓦小時 = 3.6 x 106 焦耳1 兆瓦時 = 3.6 x 109 焦耳1 千兆瓦時 = 3.6 x 1012 焦耳1 噸油當量 = 4.1868 x 1010 焦耳1 百萬噸油當量 = 4.1868 x 1016 焦耳

http://www.energyland.emsd.gov.hk/tc/energy/principle/measuring.html

1. 能源需求2. 太陽光

1.太陽能2.單位換算3.太陽光譜4.空氣質量

3. 太陽能電池4. 聚光型太陽能電池

http://www.stellarnet.us/popularconfigurations_radiosystems_solar.htm

Solar Spectra

http://www.newport.com/Introduction-to-Solar-Radiation/411919/1033/content.aspx

Blackbody Radiation Spectrum OverlayThe irradiance of the sun on the outer atmosphere when the sun and earth are spaced at 1 AU - the mean earth/sun distance of 149,597,890 km - is called the solar constant. Currently accepted values are about 1360 W m-2 (the NASA value given in ASTM E 490-73a is 1353 ±21 W m-2). The World Metrological Organization (WMO) promotes a value of 1367 W m-2. The solar constant is the total integrated irradiance over the entire spectrum (the area under the curve in Fig. 1 plus the 3.7% at shorter and longer wavelengths).

Excellent Explanation

Planck's law describes the spectral radiance of electromagnetic radiation at all wavelengths from a black body at temperature T. As a function of frequency ν, Planck's law is written as

or It can be converted to an expression for I'(λ,T) in wavelength units by substituting ν by c / λ and evaluating

or

  

and from , we have so or

The above equation is energy per unit wavelength per unit solid angle.

http://www.phy.ntnu.edu.tw/ntnujava/index.php?PHPSESSID=4rca98puqinss268nt2ibeb051&topic=427.0

Black body Radiation

http://www.creativecrash.com/maya/downloads/shaders/c/black-body-radiation

Black-body radiation is the type of electromagnetic radiation within or surrounding a body in thermodynamic equilibrium with its environment, or emitted by a black body (an opaque and non-reflective body) held at constant, uniform temperature. The radiation has a specific spectrum and intensity that depends only on the temperature of the body.

Peter Theodore Landsberg (1990). "Chapter 13: Bosons: black-body radiation". Thermodynamics and statistical mechanics (Reprint of Oxford University Press 1978 ed.). Courier Dover Publications. pp. 208 ff. ISBN 0-486-66493-7.

http://webs.mn.catholic.edu.au/physics/emery/prelim_cosmic.htm

Black body Radiation Curves

http://www.eso.org/public//outreach/eduoff/aol/market/experiments/advanced/skills303.html

Black body Radiation Curve at 5800 K

http://www.4thtransition.ws/index.php/reflection/energy-information/biosphere/

The spectrum of the Sun's solar radiation is close to that of a black body with a temperature of about 5,800 K peaking at a wavelength of 500 nm.

http://phet.colorado.edu/sims/blackbody-spectrum/blackbody-spectrum_en.html

There is an online, interactive tool from the University of Colorado for investigating the spectrum of various blackbodies. Here is the link to run it online: PhET Interactive Simulation of the Blackbody Spectrum.

Interactive tool for Black Body Radiation

Simple Solar Spectral Model for Direct and Diffuse Irradiance

http://rredc.nrel.gov/solar/pubs/spectral/model/section2.html#2

1. Black body radiation spectrum as overlay curve2. Terrestrial absorption

1) RAYLEIGH SCATTERING2) AEROSOL SCATTERING AND ABSORPTION3) WATER VAPOR ABSORPTION4) OZONE AND UNIFORMLY MIXED GAS ABSORPTION

3. Fraunhofer lines

http://www.cnyo.org/tag/rayleigh-scattering/

• Selective scattering (or Rayleigh scattering) occurs when certain particles are more effective at scattering a particular wavelength of light. Molecules much smaller than the wavelength of the radiation, like oxygen and nitrogen for example, are more effective at scattering shorter wavelengths of light (blue and violet). The selective scattering by air molecules is responsible for producing our blue skies on a clear sunny day.

• Another type of scattering (called Mie Scattering) is responsible for the white appearance of clouds. Cloud droplets with a diameter of 20 micrometers or so are large enough to scatter all visible wavelengths more or less equally. This means that almost all of the light which enters clouds will be scattered. Because all wavelengths are scattered, clouds appear to be white.

http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/opt/mch/sct.rxml

Rayleigh Scattering and Mie Scattering

1r

1r

Rayleigh Scattering and Mie Scattering

r

x

Scattering

Absorption by Terrestrial Molecules (Telluric lines)

http://acd.ucar.edu/textbook/ch15/fig1.html

http://www.eternalsun.com/technology/aaa-accuracy/

AM1.5 Global Solar Spectrum

http://www.astrosurf.com/buil/us/spe2/hresol4.htm

http://www.pvlighthouse.com.au/resources/optics/spectrum%20library/spectrum%20library.aspx

AM1.5 Global Solar Spectrum

OH 2

2O

The Earth’s atmosphere is not completely opaque to longwave. There is a transparent transmission band extending from 8 to 13 microns, in the center of the terrestrial thermal black body curve. This allows up to 30% of the longwave to escape.

http://wattsupwiththat.com/2010/11/27/people-living-in-glass-planets/

Black-body temperature 254.3 K (Earth)

Transparent Window of Atmosphere

"Spectrum of blue sky" by Spectrum of blue sky.png : Remember the dotDerivative work : Eric Bajart - Spectrum of blue sky.png. Licensed under GFDL via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Spectrum_of_blue_sky.svg#/media/File:Spectrum_of_blue_sky.svg

In the Sun, Fraunhofer lines are seen from gas in the outer regions of the Sun, which are too cold to directly produce emission lines of the elements they represent. (seen as absorption lines)

Fraunhofer Lines

http://en.wikipedia.org/wiki/Fraunhofer_lines

"Fraunhofer lines" by Fraunhofer_lines.jpg: nl:Gebruiker:MaureenVSpectrum-sRGB.svg: PhroodFraunhofer_lines_DE.svg: *Fraunhofer_lines.jpg: Saperaud 19:26, 5. Jul. 2005derivative work: Cepheiden (talk)derivative work: Cepheiden (talk) - Fraunhofer_lines.jpgSpectrum-sRGB.svgFraunhofer_lines_DE.svg. Licensed under Public Domain via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Fraunhofer_lines.svg#/media/File:Fraunhofer_lines.svg

Labeling of Fraunhofer Lines

http://www.freeenergyshop.eu/reviews/spectro-chrome-light-therapy/

Dark lines in the solar spectrum are caused by absorption by chemical elements in the Solar atmosphere. Some of the observed features were identified as telluric lines originating from absorption in oxygen molecules in the Earth's atmosphere.

http://en.wikipedia.org/wiki/Fraunhofer_lines

Telluric Spectrum

The solar spectrum from 2958 to 5400 Å is essentially clear of any terrestrial lines. Red of 5400 Å weak H2O lines begin to appear, at first two weak H2O bands (Camy-Peyret et al. 1985). By 5790 Å H2O is joined by O2. Thus for solar flux spectra obtained from ground based facilities, a correction for the telluric spectrum should be undertaken. The discrete terrestrial absorbers are illustrated in the figure. It is apparent from the figure that telluric lines have a substantial effect on a large part of the visible and near-infrared spectrum.

The Astrophysical Journal Supplement Series, 195:6 (8pp), 2011 July

The near infrared night sky of Castanet-Tolosan observatory. The sky line emission background is here detected during an observation of SS433 object with a LISA spectrograph (IR version - R = 800).

Emission lines identification in the sky background of SS433 spectrum. "blue" labeled line are artificial (HPS lamps). Note the telluric airglow emission at 6300 A and the rich atmospheric OH spectrum.

http://www.astrosurf.com/buil/us/spe2/hresol4.htm

Illustration of Telluric Contamination

HPS street lamp view from my balcony observatory (Castanet-Tolosan observatory) !

http://pveducation.org/pvcdrom/appendices/standard-solar-spectra

• The AM1.5 Global spectrum is designed for flat plate modules and has an integrated power of 1000 W/m2 (100 mW/cm2).

• The AM1.5 Direct (+circumsolar) spectrum is defined for solar concentrator work. It includes the direct beam from the sun plus the circumsolar component in a disk 2.5 degrees around the sun. The direct plus circumsolar spectrum has an integrated power density of 900 W/m2.

• The AM0 spectrum is the standard spectrum for space applications and has an integrated power of 1366.1 W/m2.

Standard Solar Spectra

http://www.instesre.org/Solar/PyranometerProtocol/PyranometerProtocol.htm

Global, Direct, and Diffuse InsolationDirect, diffuse, and total insolation for a standard atmosphere, with relative air mass of 1.5.

Global Horizontal Radiation - also called Global Horizontal Irradiance; total solar radiation; the sum of Direct Normal Irradiance (DNI), Diffuse Horizontal Irradiance (DHI), and ground-reflected radiation; however, because ground reflected radiation is usually insignificant compared to direct and diffuse, for all practical purposes global radiation is said to be the sum of direct and diffuse radiation only

GHI = DHI + DNI * cos (Z) where Z is the solar zenith angle.

http://rredc.nrel.gov/solar/glossary/gloss_g.html

Global, Direct, and Diffuse Insolation

DiffusereflectedGround

Direct

1. 能源需求2. 太陽光

1.太陽能2.單位換算3.太陽光譜4.空氣質量

3. 太陽能電池4. 聚光型太陽能電池

"Simulated direct irradiance spectra for air mass=0 to 10 with SMARTS 2.9.5" by Solar Gate - My own calculations and graphing. Licensed under CC BY-SA 3.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Simulated_direct_irradiance_spectra_for_air_mass%3D0_to_10_with_SMARTS_2.9.5.png#/media/File:Simulated_direct_irradiance_spectra_for_air_mass%3D0_to_10_with_SMARTS_2.9.5.png

http://en.wikipedia.org/wiki/Simple_Model_of_the_Atmospheric_Radiative_Transfer_of_Sunshine

Solar Spectra at Various Air Masses

Air Mass (AM)

AM0 The solar spectrum outside the atmosphere, approximated by the 5,800 K black body, is referred to as "AM0", meaning "zero atmospheres".

The spectrum after travelling through the atmosphere to sea level with the sun directly overhead is referred to, by definition, as "AM1". This means "one atmosphere".

AM1

The spectrum after travelling through “1.5 atmosphere” thickness to sea level, corresponding to a solar zenith angle of =48.2°.

AM1.5

48.2o

1L 5.1L

The air mass coefficient defines the direct optical path length through the Earth's atmosphere, expressed as a ratio relative to the path length vertically upwards, i.e. at the zenith.

o1.60

o2.48

level Sea

0 AM 1 AM

1.5 AM

2 AM

1L5.1L2L

1

AML

LX X

layerAir

Air Mass Coefficient (Approximation)

The air mass coefficient defines the direct optical path length through the Earth's atmosphere, expressed as a ratio relative to the path length vertically upwards, i.e. at the zenith.(reasonably accurate for values of up to around 75o)

Purpose of Introducing Air Mass

The original purpose of introducing the idea of air mass is to specify the zenith angle of solar irradiance so that the final irradiance power flux can be estimated by consideration of both (1) the attenuation of the irradiance passing through the atmosphere and (2) the attenuation by increased angle of incident.

angle of incident

However, the estimation is complicated and the precise values still have to resort to experiment measurements. (especially true at high zenith angles)

http://www.greenrhinoenergy.com/solar/radiation/spectra.php

Air Mass Coefficient (Spherical Model)

Air Mass Coefficient (Modified Spherical)Schoenberg, E. 1929. Theoretische Photometrie, Über die Extinktion des Lichtes in der Erdatmosphäre. In Handbuch der Astrophysik. Band II, erste Hälfte. Berlin: Springer.

Spherical model of the Earth’s atmosphere: Geometry for computing a diagonal path through the Earth’s atmosphere. Atmospheric effects on optical transmission, at an angle z to the normal, can be modelled as a path of length s, as if the atmosphere is concentrated uniformly in approximately the lower 9 km. This path is known as the Airmass. The Air mass coefficient is defined as the ratio s/yatm. This model does not apply at non-optical wavelengths where higher layers of the atmosphere affect transmission, for example: the ozone layer at higher ultraviolet frequencies and the ionosphere at lower radio frequencies.

Courtesy of Neil Clarke

http://en.wikipedia.org/wiki/File:Airmass_geometry.png

Essentially all the atmospheric effects are due to the atmospheric mass in the lower half of the Troposphere.

Spherical

Plane Parallel

Kasten and Young (1989)

Kasten & Young

Plane Parallel

Spherical

(A.1)

(A.2)

(A.3)

Kasten F, Young AT. Revised optical air mass tables and approximation formula. Applied Optics [Internet]. 1989 ;28:4735–4738. Available from: http://ao.osa.org/abstract.cfm?URI=ao-28-22-4735

http://www.pveducation.org/pvcdrom/properties-of-sunlight/air-mass

Air Mass Coefficient (Schoenberg)

Hardly any difference for z < 70o.

Z AM formula ASTM G-173

degree W/m2 W/m2

- 0 1353 1347.9

0° 1 1040 -

23° 1.09 1020 -

30° 1.15 1010 -

45° 1.41 950 -

48.2° 1.5 930 1000.4

60° 2 840 -

70° 2.9 710 -

75° 3.8 620 -

80° 5.6 470 -

85° 10 270 -

90° 38 20 -

where solar intensity external to the Earth's atmosphere Io = 1.353 kW/m2, and the factor of 1.1 is derived assuming that the diffuse component is 10% of the direct component.

Formula

Meinel, A. B. and Meinel, M. P. (1976). Applied Solar Energy Addison Wesley Publishing Co.

Standard Solar Irradiance Power

Area of cross section of earth sphere passing through sphere center= r2 = (40000 / 2 / )2 = 1.2732 108 km2

Circumference of earth sphere 40000 km ( = D)

Non-reflected irradiance (power flux)

22223

15

8287.95957

)10(

10

1027.1

122

1027.1

122

cm

mW

m

W

m

W

km

PW

Energy FluxPower

174 PW 5,487,264 EJ/yr 1367 W/m2

3,850,000 EJ/yr122 PW 957 W/m2

Total

Non-reflected

Equivalence of Solar Fluxes

Compared with formula value of 1040 W/m2 at AM1.

Peak Sun Hours

The average daily solar insolation in units of kWh/m2 per day is sometimes referred to as "peak sun hours". The term "peak sun hours" refers to the solar insolation which a particular location would receive if the sun were shining at its maximum value for a certain number of hours. Since the peak solar radiation is 1 kW/m2, the number of peak sun hours is numerically identical to the average daily solar insolation. For example, a location that receives 8 kWh/m2 per day can be said to have received 8 hours of sun per day at 1 kW/m2. Being able to calculate the peak sun hours is useful because PV modules are often rated at an input rating of 1kW/m2.

http://www.pveducation.org/pvcdrom/properties-of-sunlight/air-mass

Please estimate the area of solar panel required to provide annual global electricity consumption of 80 EJ, assuming the solar panel is located at a location that receives 5 kWh/m2 per day, and the energy conversion efficiency of solar panel is 44%.

Exercise

http://www.electrosolar.co.uk/page1.htm

The above map shows the area of PV cells of current efficiency (10%) required to supply ALL the WORLDS current energy requirements (electrical/transport/heating!). The RED area shows the area required if the efficiency approached 100%.

Solar Energy is Abundant

"SolarGIS-Solar-map-South-And-South-East-Asia-en" by SolarGIS © 2012 GeoModel Solar. Licensed under CC BY-SA 3.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:SolarGIS-Solar-map-South-And-South-East-Asia-en.png#/media/File:SolarGIS-Solar-map-South-And-South-East-Asia-en.png

http://en.wikipedia.org/wiki/Insolation

)(/3651 2 annualmkWhhoursunpeak

Solar Irradiance

( 工研院能資所 2000 年 統計 )

30

140

6050

0

20

40

60

80

100

120

140

石油 煤礦 鈾礦 天然氣

使用年限評估( )年

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