PPT On Photovoltaic System

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Photovoltaic System Presentation Transcript:
1.Introduction

2.PV System Overview

3.Harnessing the Sun
Commonly known as solar cells, photovoltaic (PV) devices convert light energy into electrical energy
PV cells are constructed with semiconductor materials, usually silicon-based
The photovoltaic effect is the basic physical process by which a PV cell converts sunlight into electricity
When light shines on a PV cell, it may be reflected, absorbed, or pass right through. But only the absorbed light generates electricity.

4.Grid-Tied System
Advantages
Easy to install
    (less components)

Grid can supply power
Disadvantages
No power if grid goes down

5.Solar Modules

6.Photovoltaic (PV) Hierarchy  

7.Available Cell Technologies   
Single-crystal or Mono-crystalline Silicon
Polycrystalline or Multi-crystalline Silicon
 Thin film
Ex. Amorphous silicon or Cadmium Telluride

8.Monocrystalline Silicon Modules
Most efficient commercially available module (11% - 14%)
Most expensive to produce
Circular (square-round) cell creates wasted space on module

9.Polycrystalline Silicon Modules
Less expensive to make than single crystalline modules
Cells slightly less efficient than a single crystalline (10% - 12%)
Square shape cells fit into module efficiently using the entire space

10.Amorphous Thin Film   
Most inexpensive technology to produce
Metal grid replaced with transparent oxides
Efficiency = 6 – 8 %
Can be deposited on flexible substrates
Less susceptible to shading problems
Better performance in low light conditions that with crystalline modules

11.PV efficiencies in world

12.Selecting the Correct Module
Practical Criteria
Size
Voltage
Availability
Warranty
Mounting Characteristics
Cost (per watt)

13.Current-Voltage (I-V) Curve

14.Effects of Temperature 
As the PV cell temperature increases above 25º C, the module Vmp decreases by approximately 0.5% per degree C

15.As insolation decreases amperage decreases while voltage remains roughly constant