Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
Christophe Ballif
1.1 Photovoltaics: Potential and Orders of Magnitude . . . . . . . . . . .
1
1.1.1 Is There Enough Energy from the Sun? . . . . . . . . . . . .
2
1.2 Photovoltaics: A Choice of Technology . . . . . . . . . . . . . . . . . .
4
1.3 Photovoltaics: Technology Evolution . . . . . . . . . . . . . . . . . . . .
5
1.4 Photovoltaics: Manufacturing Chain and Efficiency Increases . . .
7
1.5 Photovoltaics: Impact of Technology on Energy
Pay-Back Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8
1.6 Beyond Silicon Single-Junction Solar Cells . . . . . . . . . . . . . . . 10
1.7 Building Integrated Photovoltaics . . . . . . . . . . . . . . . . . . . . . . . 12
1.8 PV in Future Energy Systems . . . . . . . . . . . . . . . . . . . . . . . . . 13
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2 Solar Spectra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Adinath Funde and Arvind Shah
2.1 Interaction of Sunlight and the Earth’s Atmosphere . . . . . . . . . . 18
2.1.1 The Solar Spectrum: Nature of Solar Energy
Reaching the Earth . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.1.2 Nature of Solar Irradiance Received on Earth’s
Surface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
2.1.3 Spectra of Sunlight, for Different Times
of the Day and for Different Atmospheric
and Environmental Conditions . . . . . . . . . . . . . . . . . . 22
2.2 Albedo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
2.3 Indoor Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
2.4 “Lux” as a Unit of Light Measurement . . . . . . . . . . . . . . . . . . 27
2.5 Moonlight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
2.6 Irradiance and Irradiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
xi
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
Christophe Ballif
1.1 Photovoltaics: Potential and Orders of Magnitude . . . . . . . . . . .
1
1.1.1 Is There Enough Energy from the Sun? . . . . . . . . . . . .
2
1.2 Photovoltaics: A Choice of Technology . . . . . . . . . . . . . . . . . .
4
1.3 Photovoltaics: Technology Evolution . . . . . . . . . . . . . . . . . . . .
5
1.4 Photovoltaics: Manufacturing Chain and Efficiency Increases . . .
7
1.5 Photovoltaics: Impact of Technology on Energy
Pay-Back Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8
1.6 Beyond Silicon Single-Junction Solar Cells . . . . . . . . . . . . . . . 10
1.7 Building Integrated Photovoltaics . . . . . . . . . . . . . . . . . . . . . . . 12
1.8 PV in Future Energy Systems . . . . . . . . . . . . . . . . . . . . . . . . . 13
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2 Solar Spectra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Adinath Funde and Arvind Shah
2.1 Interaction of Sunlight and the Earth’s Atmosphere . . . . . . . . . . 18
2.1.1 The Solar Spectrum: Nature of Solar Energy
Reaching the Earth . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.1.2 Nature of Solar Irradiance Received on Earth’s
Surface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
2.1.3 Spectra of Sunlight, for Different Times
of the Day and for Different Atmospheric
and Environmental Conditions . . . . . . . . . . . . . . . . . . 22
2.2 Albedo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
2.3 Indoor Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
2.4 “Lux” as a Unit of Light Measurement . . . . . . . . . . . . . . . . . . 27
2.5 Moonlight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
2.6 Irradiance and Irradiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
xi