©Fraunhofer ISE/Foto: Guido Kirsch
Materialinnovationen für die Solarenergie
Impulsvortrag
Andreas W. Bett
Fraunhofer Institute für Solare Energiesysteme ISE
Materials for the European Green Deal Online, 9. September 2021
www.ise.fraunhofer.de
© Fraunhofer ISE
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1,5*10
18kWh/Jahr
10.000 times the global energy demand
Solarthermal
Photovoltaics
Transformation of the Global Energy Supply to be CO
2-free in 2050 Market: Photovoltaic is Needed in Huge Quantities!
10 TW
18 TW
31 TW
43 TW
63 TW
EU: 9 TW G: ~ 0.5 TW Photovoltaics
Wind Fossil Oil
Fossil Gas Fossil Coal
2021: 0.65 TW
© Fraunhofer ISE
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The Need of Huge Quantities Materials and Resources
10 TW
18 TW
Quelle: SMA
Needs enormous resources:
~ 300.000 km² area
~ 3.000.000.000 metric tons material (glass, silicon, silver, polymers…) Circular Economy is mandatory!
High efficiency is mandatory!
Innovation: New Production Technology for Materials and Materials for Record Cell Efficiencies and
Today: 80 % Passivated Emitter and Rear Cell (PERC) and 15 % Al-BSF solar cells in the world market; all made of Silicon material
Recent Laboratory Records
(tandems needs additionals materials)
Si-TOPCon: 26.0 % (Europe) BJ-HJT: 26.7% (Japan)
Pero/Si-Tandem: 29.5% (Europe) III-V/Si-Tandem: 34.5% (Europe)
Industrial values
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Innovation Material Production Silicon Wafer – Today´s Process
Ref: NexWafe GmbH, Freiburg Germany
Innovation Material Production Silicon Wafer – A New Process
Si pre-wafer
Si pre-wafer
3 - Si Epitaxy
Si pre-wafer
4 - Removal
re-use of pre-wafer
1 µm
1 – Electrochemical etching
Si pre-wafer
Si pre-wafer
2 - Reorganisation
1 µm
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Innovation Material Production Silicon Wafer – New Process
Ref: NexWafe GmbH, Freiburg Germany
Innovation: Going Beyond the Limit Using one Material Build a Tandem Solar Cell
The sun has a wide spectrum of colours / wavelengths
Only one wavelength can be used efficiently by one solar cell type
Two solar cell materials can split up the spectrum
Monolithic
Tandem solar cells -2-1 Intensity[W mnm] -
+
UV Visible Infrared
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Tandem PV
Perovskites on Silicon
Silicon
-
+
Perovskite Silicon
Tandem PV
Perovskites on Silicon
Perovskite
Silicon Silicon
Solar Cell Perovskite Solar Cell
-
+
Perovskite Silicon
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Tandem PV
III-V-Semiconductor on Silicon: Wafer-Bonded
Three materials: GaInP, AlGaAs, Si
Very high voltage > 3 V
Si pn-junction
Si solar GaInP solar cell AlGaAs solar cell
~ 5 µm200 µm
R. Cariou et al., Nature Energy 2018
Wafer-Bonded Solar Cell
Si solar Si pn-junction
Si solar GaInP solar cell AlGaAs solar cell
~ 5 µm200 µm
Inverted grown dual junction solar cell
Si pn-junction
GaAs substrate GaInP solar cell AlGaAs solar cell
Si solar
Sipn -junc
tion bstra GaAssu
te
GaInP so lar cell
AlGaAss olar cell
© Fraunhofer ISE
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Tandem PV
III-V-Semiconductor on Silicon
Three materials: GaInP, AlGaAs, Si
Very high voltage > 3 V
Si pn-junction
Si solar GaInP solar cell AlGaAs solar cell
~ 5 µm200 µm
R. Cariou et al., Nature Energy 2018
Technology Status 2-Terminal III-V/Si Tandem Direct Epitaxy Growth on Silicon
5.4 5.5 5.6 5.7
0.5 1.0 1.5 2.0
2.5 AlP
AlAs
Si
Ge GaP
GaAs
0.3 0.2 0.1
0.8 0.7 0.6 0.5 0.4 0.3
Ga0.51In0.49P
Bandgap [eV]
Lattice constant [Å]
5E7 cm-²
< 1E5 cm-²
2015
2018
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Conclusions
Innovations in material science are of utmost importance for solar energy
Recyclability towards circular economy
Sustainability in respect to material availability and process flow
Innovations on component and system level mandatory
Cell, module, inverter, installation……..
Fraunhofer Institut for Solar Energy Systems ISE
Prof. Andreas W. Bett
www.ise.fraunhofer.de
andreas.bett@ise.fraunhofer.de
