space photovoltaic solar cells
TRANSCRIPT
Faculty of Engineering School of Photovoltaic and Renewable Energy Engineering
Space Photovoltaic Solar Cells
10th July 2018 3rd CubeSat Innovation Workshop
N.J.Ekins-Daukes
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• 1367W/m2 in Earth Orbit.
• <1000W/m2 at Earth’s surface.
Silicon Space Solar Cell
!3N.Fatemi et al., “Solar Array Trades Between Very High-Efficiency Multi-Junction and Si Space Solar Cells”, Proc. IEEE PVSC, p1083 (2000)
AzurSpace S32
Weight : 32mg/cm2 Efficiency : 16.9% (BOL) Specific Power : 0.71W/g (BOL) Power density : 229 W.m-2 (BOL) 149 W.m-2 (EOL)
Multi-Junction Solar Cell : Concept
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Y
X
Ge
Load
1
2
3
1 2 3
Triple Junction Solar Cell : InGaP/GaAs/Ge
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Triple Junction Solar Cell
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AzurSpace 3G30C
Weight : 50mg/cm2 Efficiency : 29.8% (BOL) Specific Power : 0.81 W/g (BOL) Power density : 403 W.m-2 (BOL) 365 W.m-2 (EOL)
Inverted Metamorphic Triple Junction Solar Cell
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IMM 3J solar cell (Sharp Corp.)
Weight : 25mg/cm2 Efficiency : 32.3% (BOL) Specific Power : 1.75W/g (BOL) Power density : 437W.m2 (BOL)
(Data from SolAero)
Inverted Metamorphic MJ Cells
Lattice parameter
Microlink Devices Inc.
Airbus Zephyr
Space PV Research @ UNSW : Interstitial Light Trapping
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A. Mellor, N. P. Hylton, S. A. Maier, and N. J. Ekins-Daukes, Sol Energy Mat. Sol. C., vol. 159, pp. 212–218, 2017. & Patent No. WO 2017/208006
Ongoing funding :US-Air Force / AOARD
Seed funding:
Space PV Research @ UNSW : 4+J solar cells & beyond..
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Molecular Beam Epitaxy @ ANFF-NSW
A/Prof. Stephen Bremner
GaAsBi
4+ junctions will enable efficiencies above 33%.
Semiconductor materials with band-gaps between 1.2-0.9eV required.
Summary
• Silicon PV is now a legacy technology: low efficiency and poor radiation tolerance.
• III-V Multi-junction technology is now standard on all commercial satellites
• 30% BOL efficiency is now routine • 32% BOL efficiency possible with IMM
technology • Research opportunities at UNSW:
• Highly radiation tolerant photovoltaic solar cells.
• >33% BOL next generation space solar cells: new low band-gap semiconductor materials to enable 4+ junction cells.
• Radiation induced defects in space solar cells (theory & experiment)
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Sharp Corp.
AzurSpace