PHOTOVOLTAIC PV LED LIGHTING

SYSTEMS

PREPARED BY-KUNAL S. MAHJAN

TE ELECTRICAL, GCOE, JALGAON.

INDEX

IntroductionSolar cellWorking of solar cellComponents of PV systemTypes of PV systemsLED Lighting Advantages and disadvantages of PV systems

Conclusion References

INTRODUCTION

Photovoltaic (PV) systems convert sunlight directly into electricity.

The heart of a photovoltaic system is a solid-state device called a solar cell.

SOLAR CELL

Solar cells are made of silicon.Treated to be positive on one side and

negative on other side.When light energy hits the cell, electrons

loose out from the atoms in the semiconductor material.

If electrical conductors are attached to the positive and negative sides, forming an electrical circuit, and the flow of released electron produces the current.

WORKING OF SOLAR CELL

A typical solar cell is composed thin wafer consisting phosphorus-doped silicon on top of boron doped silicon layer.

An electrical field is created near the top of surface of cell where these two materials are in contact, called the P-N junction.

When sunlight strikes the surface of PV cell, these electric field provides momentum and direction to light stimulated electrons, resulting in flow of current when solar cell is connected to electrical load.

Every single photovoltaic cell has small dimensions and generally produces a power between 1 to 3 watts at 0 to 5 volts.

If several cells are connect themselves ,creates bigger units called Modules. The modules are connected to form panels that produces wanted power.

Solar modules ,battery ,inverter ,charge controller are the main components of PV system.

This four components occupies more than two-thirds of the total cost of system.

Batteries are used to store the electrical energy generated by photovoltaic modules.

Power can be drawn out from the batteries whenever required during the day or night.

Direct current systems which power AC load must use an Inverter.

The use of inverter increases the cost of system.Charge regulator limits the rate at which current is drawn or

added to batteries.Here we are using LED as a load. Inverter converts DC to AC.

COMPONENTS OF PV SYSTEM

TYPES OF PV SYSTEMS

Mainly classified as Grid connected and stand-alone systems. oGrid connected PV systems• Grid connected PV systems are designed to operate in

parallel with the electrical utility grid.• The main component of grid connected PV system is

inverter. The inverter converts DC power produced by PV array into AC power as required by the utility grid.

oStand-Alone PV systems• Stand-alone PV systems are generally designed to supply

DC and/or AC electrical loads.• The simplest example of stand-alone PV system is directly

connected DC load.

Recently solar PV are coupled with Light Emitting Diodes [LEDs] to give energy efficient light.

Recent advancements in LED technology have led to development of white light emitting diodes[WLEDs]

WLEDs provide a bright white light that’s ideal for domestic lighting.

The advantage of using LEDs with solar PV system is that the LED requires very much lower power wattage

Therefore the size and cost of solar system is much reduced.

LED LIGHTING

PV LED LIGHTING

In our country there are about 300 clear sunny days in a year and hence solar energy is widely available.

There is a vast scope for solar sector in India

There is still over 100000 villages in the country to be electrified.

Recognizing the importance of PV technology Government is also implanting a comprehensive pregramme in solar sector.

INDIA HAS LOT OF SUN LIGHT

ADVANTAGES AND DISADVANTAGES

AdvantagesFuel is free and easily available.Easily expandable.No noise pollution or other type of pollution.PV systems which are properly design and properly

installed required nominal maintenance.

DisadvantagesHigh cost of PV modules and equipments is the primary

limiting factor.The surface area required for the PV array may be limiting

factor.

CONCLUSION

It is light to light conversion.It is very simple system to implement.LEDs are used because they need very

small voltage to operate and more life time.

Although cost is major factor but PV systems are long life durable and long time service provider .

REFERENCES

W C Adams, 'Photovoltaic solar energy generation'.

http://www.thinkelectrics.com/solar-pv/http://www.lrc.rpi.edu/programs/NLPIP/

lightingAnswers/photovoltaic/02-photovoltaic-what-is-PV.asp

http://free-energi.com/index.php?a=4http://portal.indiainfoline.com/

datamonitor/Energy/Number-of-Towns-and-Villages-Electrified-in-India.aspx

THANK YOU

For more details contact

Kunalmahajan03@gmail.com