Photovoltaics

Photovoltaics

Photovoltaics

PV Applications

Multicrystalline siliconcasting, wafers, and PV cells (

Photovoltaics

PV cells

Photovoltaics

Cross-sectional view of a PV cell, showing the photo-receptive surface and the p/n junction

Photovoltaics

An n-type material has an increased number of electrons

the p-type material has vacancies as a result of missingelectrons (p = positive).

The p-n junction is the critical component of afunctioning solar cell.

Photovoltaics

The Photovoltaic Principle - Cells

•The majority of the light is absorbed in the “p-silicon” layer

• some electrons push through the p-n junction into the n-silicon layer.

•The freed electrons flow through the wire grid

Photovoltaics

The Photovoltaic Principle

•One single-crystal silicon solar cell with a surface area of approximately 100 cm2 (16 in2) generates a current of 3 A at a voltage of 0.5 V when exposed to full sunshine.

Photovoltaics

The Photovoltaic Principle

Photovoltaics

Efficiencies

Photovoltaics

PV Modules

Flexible photovoltaic modules made of amorphous silicon (a-Si) on stain - less steel

Photovoltaics

Photovoltaics

•The light-generated current flows out of the cell surface and through a metal grid called the front contact.

•The cell’s bottom layer is called the back contact and forms a bridge to an external circuit.

Photovoltaics

The Photovoltaic Principle - Modules

I-V curve and characteristicparameters for a typical module

Photovoltaics

• Open circuit voltage (VOC): no current.

• Pn under STC: peak power (Vn and In).

• Short circuit current (ISC)

Photovoltaics

The Photovoltaic Principle - Modules

An example of a typical PV module data sheet

Photovoltaics

Solar cells 100 mm x 100 mm, 36 in series

• Voltage is derated by 0.0022 V/K above STC

• In bright sunlight module is 35°F-70°F above the ambient temperature.

Photovoltaics

The Photovoltaic Principle - Modules

Photovoltaics

PV System Arrangement

Photovoltaics

Photovoltaics

Advantages of PV

Photovoltaics

Industry Claim

Photovoltaics

*)Assuming volume installations. Individual rooftop systems can be up to twice this price

Photovoltaics

More Cautious AEE Assessment

Photovoltaics

Photovoltaics

Photovoltaics

Photovoltaics

Holographic PV Planer Concentrator - HPPC

Photovoltaics

Holographic PV Planer Concentrator - HPPC

Solar Thermal

Solar Thermal

Conventional Flat Plate Collector

Solar Thermal

Passive Thermo-siphon Collector

Solar Thermal

Evacuated Tube Collector

Solar Thermal

Solar Hot Water System

Solar Thermal

Solar Thermal

Solar Thermal

Solar Thermal