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Photovoltaics
Technology Components and Systems
Applications
Clemson Summer School
4.6. – 6.6.2007
Dr. Karl Molter
FH Trier
www.fh-trier.de/~molter
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
2
Content
1. Solar Cell Physics
2. Solar Cell Technologies
3. PV Systems and Components
4. PV Integration into buildings
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
3
IntroductionPhotovoltaics, or PV for short, is a solar power technology that
uses solar cells or solar photovoltaic arrays to convert light from the sun into electricity.
Photovoltaics is also the field of study relating to this technology and there are many research institutes devoted to work on photovoltaics. The manufacture of photovoltaic cells has expanded in recent years, and major photovoltaic companies include BP Solar, Mitsubishi Electric, Sanyo, SolarWorld, Sharp Solar, and Suntech. Total nominal 'peak power' of installed solar PV arrays was around 5,300 MW as of the end of 2005 and most of this consisted of grid-connected applications. Such installations may be ground-mounted (and sometimes integrated with farming and grazing) or building integrated.
Financial incentives, such as preferential feed-in tariffs for solar-generated electricity, have supported solar PV installations in many countries including Germany, Japan, and the United States.
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
4
1. Solar Cell Physics
• Solar Cell and Photoelectric Effect
• The p/n-Junction
• Solar Cell Characteristics
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
5
History
• 1839: Discovery of the photoelectric effect by Bequerel
• 1873: Discovery of the photoelectric effect of Selen (change of electrical resistance)
• 1954: First Silicon Solar Cell as a result of the upcoming semiconductor technology ( = 5 %)
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
6
Solar Cell and Photoelectric Effect
1. Light absorptionh
-
+2. Generation of „free“
charges
3. effective separation of the charges
Result: wearless generation of electrical Power by light absorption
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
7
energy-states in solids:Band-Pattern
Atom Molecule/Solid
ener
gy-s
tate
s
• • • • • • • •
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
8
energy-states in solids:Insulator
electron-energyconduction-band
valence-band
Fermi-level EF
bandgap EG
(> 5 eV)
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
9
Terms:
Fermilevel EF: limit between occupied and non occupied energy-states at T = 0 K (absolute zero)
valence-band: completely occupied energy-band just be-
low the Ferminiveau at T = 0 K, theelectrons are „fixed“ (tightly bound)
inside the atomic structure
conduction-band:energy-band just above the valence-band, the electrons can move „freely“
bandgap EG: distance between valance-band andconduction band
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
10
energy-states in solids :metal / conductor
electron-energy
conduction-band
Fermi-level EF
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
11
energy-states in solids:semiconductor
electron-energy
conduction-band
valence-band
Fermi-level EF
bandgap EG
( 0,5 – 2 eV)
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
12
Electron-EnergyAt T=0 (absolute zero of temperature) the electrons occupy the
lowest possible energy-states. They can now gain energy in two ways:
• Thermal Energy: kT (k = Boltzmanns Constant, 1.381x10-23 J/K, T = absolute temperature in Kelvin)
• Light quantum absorption: h (h = Plancks Constant, h = 6.626x10-34 Js, = frequency of the light quantum in s-1).
If the energy absorbed by the electron exceeds that of the bandgap, they can leave the valence-band and enter the conduction-band:
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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energy-states in solids:energy absorption and emission
electron-energy
conduction-band
valence-band
EF
+
-
h
Generation
+
-
h
Recombination
x
x
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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energy-states in semiconductorsphysical properties:
thermal viewpoint: The larger the bandgap the lower is the conductivity. Increasing temperature reduces the electrical resistance (NTC, negative temperature coefficient resistor)
optical viewpoint: the larger the bandgap the lower is the absorption of light quantums. Increasing light irradiation decreases the electrical resistance (Photoresistor)
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
15
doping of semiconductorsIn order to avoid recombination of photo-induced charges and to „extract“ their energy to an electric-device we need a kind of internal barrier. This can be achieved by doping of semiconductors:
IIIB IVB VB
Si14
B 5
P15
„Doping“ means in this case the replacement of original atoms of the semiconductor-material (e.g. Si) by different ones (with slightly different electron configuration). Semiconductors like Silicon have four covalent electrons, doping is done e.g. with Boron or Phosphorus:
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
16
N - Doping
Si Si
Si
Si
Si
Si
Si
Si
Si
P+
-
n-conducting Silicon
-
crystal view
conduction-band
valence-band
EF
- - - - -P+ P+ P+ P+ P+
majority carriers
donator level
energy-band view
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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P - Doping
Si Si
Si
Si
Si
Si
Si
Si
Si
p-conducting Silicon
B- +
+
crystal
conduction band
valence-band
EF B- B- B- B- B-
majority carriersacceptor level
+ + + + +
energy-band view
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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p – type region
EFB- B- B- B- B-
+ + + +
n – type region
- - - -P+ P+ P+ P+ P+
p/n-junction without lightBand pattern view
+
--Diffusion
+
Diffusion
internal electrical field
+ -Ed
Ud
depletion-zone
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
19
p–type region
EFB- B- B- B- B-
+ + + +
n–type region
- - - -P+ P+ P+ P+ P+
irradiated p/n-junctionband pattern view (absorption p-zone)
+
-
+
photocurrent
Internal electrical field
+ -Ed
Ud
depletion-zoneE = h
-
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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p/n–junction without irradiation(semiconductor diode)
crystal view
n-silicon
- - - - - - - - - - - -
- - - - - - - - - - - -
- - - - - - - - - - - -
- - - - - - - - - - - -
p-silicon
+ + + + + + + + + + + +
+ + + + + + + + + + + +
+ + + + + + + + + + + +
+ + + + + + + + + + + +
+
-diffusion
-
+
electrical fieldE- - - - - - - - - - - -+ + + + + + + + + + + ++ + + + + + + + + + + +
+ + + + + + + + + + + +
- - - - - - - - - - - -
- - - - - - - - - - - -
-
+
depletion zone
+
-
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
21
p/n–junction with irradiationcrystal view
n-silicon
- - - - - - - - - - - -
- - - - - - - - - - - -
- - - - - - - - - - - -
- - - - - - - - - - - -
p-silicon
+ + + + + + + + + + + +
+ + + + + + + + + + + +
+ + + + + + + + + + + +
+ + + + + + + + + + + +
+
-diffusion
-
+
electrical fieldE- - - - - - - - - - - -+ + + + + + + + + + + +
+-
h
-
-
-
+
depletion zone
-
+
drift
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
22
Charge carrier separation within p/n–junction
diffusion:from zones of high carrier concentration to zones of low carrier concentration (following a gradient of electrochemical potential)
drift:driven by an electrostatic field established across the device
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
23
Antireflection-coating
The real Silicon Solar-cell
~0,2µm
~300µm
Front-contact
Backside contact
n-region
p-region
-
+
h
depletion zone
- - - - - - - - - -+ + + + + + + + + +
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
24
Equivalent circuit of a solar cell
RP
USG
RSISG
RL
UL
ILID
UD
currentsource
IPH
IPH: photocurrent of the solar-cell
ID /UD: current and voltage of the internal p-n diode
RP: shunt resistor due to inhomogeneity of the surface and loss-current at the solar-cell edges
RS: serial resistor due to resistance of the silicon-bulk and contact materialISG/USG: Solar-cell current and voltage
RL/IL/UL: Load-Resistance, current and voltage
ISG = IL, USG = UL
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
25
Solar-Cell characteristics
ID ISG
RLUD=USG
ID
ISG / PSG
USG
solar-cellcharacteristics
ISG = I0 = IK
RL=0 RL=
Power
UD
diode-characteristic
ID
U0
Load resistance
UMPP
MPP
IMPP
MPP = Maximum Power Point
simplified circuit
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
26
Solar-cell characteristics
• Short-current ISC, I0 or IK:• mostly proportional to irradiation• Increases by 0,07% per Kelvin
• Open-voltage U0, UOC or VOC:• This is the voltage along the internal diode• Increases rapidly with initial irradiation• Typical for Silicon: 0,5...0,9V• decreases by 0,4% per Kelvin
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
27
Solar cell characteristics
• Power (MPP, Maximum Power Point)• UMPP (0,75 ... 0,9) UOC
• IMPP (0,85 ... 0,95) ISC
• Power decreases by 0,4% per Kelvin
• The nominal power of a cell is measured at international defined test conditions(G0 = 1000 W/m2, Tcell = 25°C, AM 1,5) in WP (Watt peak).
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
28
Solar cell characteristics
• The fillfactor (FF) of a solar-cell is the relation of electrical power generated (PMPP) and the product of short current IK and open-circuit voltage U0
FF = PMPP / U0 IK
• The solar-cell efficiency is the relation of the electrical power generated (PMPP) and the light irradiance (AGG,g) impinging on the solar-cell :
= PMPP / AGG,g
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
29
Solar-cell characteristics (cSi)P = 0,88W, (0,18) P = 1,05W, (0,26)
P = 0,98W, (0,29)
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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Solar-cell characteristics
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
31
2. Solar-cell Technologies
• Materials
• Technologies
• Market shares and development
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
32
MaterialsDefinition of semiconductor: This is a matter of electron configuration
Extract of periodic table:
Si14
Silicon (Si)
Ge32
Germanium (Ge)
Ga31
As33
Gallium-Arsenide (GaAs)
Cd48
Te52
Cadmium-Telluride (CdTe) P
15
In49
Indium-Phosphorus (InP)
Al13
Sb
51
Aluminium-Antimon (AlSb)
Copper, Indium, Gallium, Selenide (CIS)
Cu29
Se34
In49
Ga31
IIB IIIB IVB VB VIBIB
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
33
Efficiency of different solar cells(Theory / Laboratory)
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
34
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
35
Arguments for different technologies
• Potentially high efficiency
• Availability of material
• Low material price
• Potentially low manufacturing costs
• Stability of characteristics for many years
• Environment friendly and non toxic Materials and manufacturing process
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
36
+ Mass production efficiency between 15 - 18% (>23% in laboratory)
– A lot of raw material needed– Raw silicon costs are strongly varying in time+ Well known production process, but consumes much
energy, optimization by EFG and band-Technology+ Very good long term stability+ material almost pollution free+ Second place in market shares
Evaluation of mono-crystalline Silicon:
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
37
Evaluation of multi-crystalline Silicon:
+ Mass production efficiency between 12 - 14%– A lot of raw material needed– Raw silicon costs are strongly varying in time+ Well known production process, consumes less
energy than mono-Si+ very good long term stability+ material almost pollution free+ First place in market shares
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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Evaluation of amorphous Silicon (a-Si):
– Mass production efficiency only 6 – 8%+ Thin-Film Technology (<1µm), only few
raw material needed+ Well known production process, consumes
far less energy than crystalline Silicon+ large area modules can be manufactured in one step– long term stability only for efficiency between 4 – 6%+ material almost pollution free
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
39
+ Mass production efficiency 11 – 14%+ Thin-Film Technology (<1µm), only few raw material
needed+ large area modules can be manufactured in one step+ good long term stability – raw material not pollution free (Se, small quantity of
Cd)
Evaluation of Copper, Indium, Diselenide (CIS)
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
40
+ Mass production efficiency up to 18%– some raw materials are rather rare– raw material very expensive– some production processes not suited for mass
production– long term stability not well known– raw material not pollution free (esp. As, Cd)
Evaluation of GaAs, CdTe and others
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
41
Production process1. Silicon Wafer-technology (mono- or multi-crystalline)
Tile-production
Plate-production
cleaning
Quality-control
Wafer
Most purely silicon
99.999999999%
Occurence:
Siliconoxide (SiO2)
= sand
melting /
crystallization
SiO2 + 2C = Si + 2CO
Mechanical cutting:
Thickness about 300µm
Minimum Thickness:
about 100µm
typical Wafer-size:
10 x 10 cm2
Link to
Producers of Silicon Wafers
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
42
Production- Processmono- or multi-
crystalline Siliconcrystal growth process
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
43
Production - Process
EFG: Edge-defined Film-fed Growth
Less energy-consumptively than crystal-growth process
Thickness: about 100µm
Only few Silicon waste, since no cutting necessary
Silicon Band-Growth Process
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
44
Production Process
semiconductor materials are evaporated on large areas
Thickness: about 1µm
Flexible devices possible
less energy-consumptive than c-Silicon-process
only few raw material needed
Typical production sizes:1 x 1 m2
Thin-Film-Process (CIS, CdTe, a:Si, ... )
CIS Module
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
45
Technology -Trends
• Thin-Film Technology– few raw material needed– demand of flexible devices– production of large area cells / modules in one step
• enhancement of cell efficiency– Tandem-cell for better utilization of the solar spektrum– Light Trapping, enhancement of the light absorption– Transparent contacts– bifacial cells
• Solar-concentrating photovoltaics
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
46
Tandem-cell
Pattern of a multi-spectral cell on the basis of the
Chalkopyrite Cu(In,Ga)(S,Se)2
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
47
Thin Si-Wafer
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
48
energy payback time (EPBT)
BOS: Balance of System = inverter, cable, transport, assembly …
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
49
Market Shares
Thin-FilmSi-Band-growth
multi-crystalline Si
mono-crystalline Si
of the main solar cell technologies
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
50
Solar-Cell Manufacturer
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
51
Worldwide installed PV-Power
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
52
In Germany installed PV-Power
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
53
PV-Module priceexperience curve: price per Wp against cumulative production
with Research & Development
without Research& Development
end of 2004
cumulative production in MWp
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
54
3. PV Systems and Components
• PV System-Technology
• Solar Irradiation
• Energy yield and savings
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
55
PV-Systems
The basic photovoltaic or solar cell typically produces only a small amount of power. To produce more power, cells can be interconnected to form modules, which can in turn be connected into arrays to produce yet more power. Because of this modularity, PV systems can be designed to meet any electrical requirement, no matter how large or how small.
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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PV ModuleA PV-Module usually is assembled by a certain amount of series-connected solar-cells
typical open-.circuit Voltage using 36 cells: 36 * 0,7V = 25V
Problem: due to series connection, the failure of one cell (defective or shadow) reduces the current through all cells!
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
57
PV Modulein order to avoid this kind of failure, cells or cell strings are bypassed by diodes which shortcut the defective orshaded cell(s) :
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
58
Grid-connected PV-System
Solar-Generator
inverter(virtualload)
DC
AC
protection-Diode
load utility-grid
Grid
The grid is involved as a temporary energy storage
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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inverter concepts
Grid
=~
=~
…
module-integrated
=~
… … …
central
=~
=~
…
…
… …
string-inverter
…
…… …
==
==
=~
multistring-inverter
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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PV – Solar Home System (SHS)with AC-Load
Solar-Generator
charge-regulator
DC
DC
Protection-Diode
Fuse
inverter
DC
AC
loadAccumulator
(storage)
Main difference to a grid connected System:- a local DC energy storage and DC/DC regulator is necessary- an additional DC/AC converter is necessary-> increase of Balance of System (BOS) costs
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
61
Solar-generator: Dimensioning I
• The solar-generator voltage and power has to be adopted to the load and storage (in case of a SHS) or the inverter (in case of a grid connected system)
• This is achieved by suitable series and parallel connection of PV-Modules
• SHS without inverter are mostly 12V or 24V and sometimes 48V DC-Systems.
• To compensate voltage loss at the charge-regulator / inverter and the cabling, the nominal voltage of the modules should always be slightly above the minimal required input voltage of the charge-regulator / inverter
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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Solar-generator: Dimensioning II
• Orientation of the module surface (Azimuth) : Northern Hemisphere to South, Southern Hemisphere to North (Deviations less than ± 30° reduce the energy gain less than 5%
• Guide: Inclination (tilt angle) ~ latitude of locationmore steeply: more energy gain during spring / autumnmore flat: more energy gain in summer
• Sun-Tracker is expensive and complicated (moving parts) and increases the energy gain by only 10 to 15%
The dimensioning of the solar generator depends also on the solar irradiation conditions of the location and the orientation of the module surface:
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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Solar irradiation characteristics(northern hemisphere, ~ 50° latitude)
tilt
south-eastsouth-west
west east
energy production with respect to optimal orientation
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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Total solar irradiation
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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Solar Irradiation in Germany
Data from 2002
Irradiation on horizontal surface between 900 (North)and 1300 (South) kWh/m² per year
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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Solar irradiation in the USA
Shown is the average radiation received on a horizontal surface across the continental United States in the month of June. Units are in kWh/m2
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
67
Solar Irradiation worlwide(kWh/m² a) on horizontal surface
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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Solar Irradiance worlwideAverage 1991-1993: (W/m²) on horizontal surface
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
69
Example: practical energy gain
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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Energy-Yieldis dependent on:
• location / Climate middle-Europe: 700 – 900 kWh per kWp installed PV-Power
• Orientation (Tilt, Azimuth)± 20° deviation ± 5% Energy-loss
• PV-Technologydetermines area needed and efficiency
• eventually additional use (aesthetics, weather proof,SHS)
• pollution free electricity generation,CO2 reduction etc.
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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Incentives for solar generated electricity (EEG, in Germany)
Grid connected system, electricity produced is totally feed into the grid
The table shows the amount paid per kWh solar electricity produced:
year 2004 2005 2006 2007 2008
Building integrated 57,4 ct 54,53 ct 51,80 ct 49,21 ct 46,75 ct
More than 30 kW 54,6 ct 51,87 ct 49,28 ct 46,82 ct 44,48 ct
More than 100 kW 54,0 ct 51,30 ct 48,74 ct 46,30 ct 43,99 ct
Facade- bonus 5,00 5,00 ct 5,00 ct 5,00 ct 5,00 ct
Open-land systems 45,7 ct 43,42 ct 40,60 ct 37,96 ct 35,49 ct
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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4. Building Integrated PV
• PV as a multifunctional part of buildings
• Examples
• further informationen
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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4.1 Weather Protection
• Rain and wind tightness
• storm resistant
• climate-change resistant
• durable
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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Example: Utility Tower in Duisburg
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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Example: roof
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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4.2 Thermal insulation
• In combination with usual heat-insulating materials
• In combination with heat insulating glass
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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Example: special roof
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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example: Swimming pool
4.6.07 - 6.6.07 Clemson Summer School 2007Dr. Karl Molter / FH Trier / [email protected]
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4.3 Heating / Air conditioning
• Combination of PV and thermal Energy-conversion (Air / Water)
• Optimization of PV Efficiency
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4.4 Shading
• Regulation by „Cell density“
• use of semitransparent cells
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Example: Shading
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4.5 Sound absorption
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4.6 Electromagnetic Absorption
• Faraday's cage principle
• Reduction of Electro smog inside of buildings
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4.7 Production of electrical energy
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Example: PV-Roof and Front,
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4.10 Design /Aesthetics
• PV facade and roof-elements are highly valuable building materials which may be adapted to many different Design-criteria
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Alwitra Solar-foil
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Solar-roof shingle
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Example: Sports-Center Tübingen
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Example: Fire-brigade
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Example: BP Showcase
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Information sources in the Internet (selected)
• U.S. Department of Energy (http://www1.eere.energy.gov/solar/technologies.html)and links within these pages
• Wikipedia(http://en.wikipedia.org/wiki/Solar_cells)and links within this page
• Software: Valentin Energy Software: PVSOL, Meteonorm(http://www.valentin.de/index_en)
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This Powerpoint Presentation can be downloadedfrom:
www.fh-trier.de/~molter
www.fh-trier.de/~molter