European Space Agency

AZUR SPACE triple solar cell 3G27/3G28 Qualification


Manufacturing and qualification of fully European triple junction solar cell. The qualification has been subdivided into 3 phases.

Phase 1: Cell 3G27-ID2*, with an efficiency of 27 % was designed for LEO applications and qualified at bare solar cell and solar assembly level for the Herschal & Planck mission requirements.
The 3G-27-ID2* cell and solar cell assembly where qualified for the Aeolus mission requirements.

Phase 2: Cell 3G28-ID2*, with an efficiency of 28% was designed for GEO application. Qualification comprised cell, SCA and coupon testing.

Phase 3: Qualification covered wing level for which the Alphabus Q-Panel was used.


The intention of the project was to produce and qualify a fully European triple junction solar cell, with a high efficiency of the sun light-to-current conversion, low temperature coefficients and excellent power-to-mass ratio, based on III-V compound semiconductor materials.

Fig.1 typical spectral response of the triple junction cell 3G28-ID2*

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The cell has been designed for geostationary missions. During the application in space the material is exposed to strong high-energy electron and proton beams, x-ray radiation and cosmic rays up to 15 years. The extreme radiation hardness of the triple-junction solar cells has been designed to meet the challenge of this environment and guarantee long-term operations in orbit.


3G28ID2* was designed as radiation hard triple solar cell for GEO-missions, with a BOL efficiency of 28%(AM0,28°C) and a remaining factor of 0,92 after 1MeV electron irradiation with a dose of 5E14.

Fig. 1 Solar cell 3G28-ID2* with integral diode.

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Sept 2003: Production and qualification of a fully European triple junction cell 3G27-ID2*.

Sept 2005: Production and qualification of the next generation of fully European triple junction cell 3G28-ID2*.

Feb 2006: Q-Panel qualification on Wing level .

Current status

The triple junction cells successfully passed all tests, performed from component up to wing level, for GEO applications.

Status date

Tuesday, April 12, 2011 - 16:34