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SOLAR ROOFSOLAR ROOF

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ContentsContents

Need for a solar roofNeed for a solar roof

What is a solar roof ?What is a solar roof ?

How energy is extracted from it ?How energy is extracted from it ? Monthly residential savings (Benefits)Monthly residential savings (Benefits)

Advantages & DisadvantagesAdvantages & Disadvantages

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StatisticsStatistics

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World Oil and Natural GasWorld Oil and Natural Gas

reserves are estimated at just 45reserves are estimated at just 45

years and 65 years respectively.years and 65 years respectively.

Coal is likely to last a little overCoal is likely to last a little over

200 years200 years

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What is a solar cell?What is a solar cell?

Solid state device that converts incident solarSolid state device that converts incident solar

energy directly into electrical energyenergy directly into electrical energy

Efficiencies from a few percent up to 20-30%Efficiencies from a few percent up to 20-30% No moving partsNo moving parts

No noiseNo noise

Lifetimes of 20-30 years or moreLifetimes of 20-30 years or more

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Cross Section of Solar CellCross Section of Solar Cell

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How Does It Work?How Does It Work?

The junction of dissimilar materials (n and p typeThe junction of dissimilar materials (n and p type

silicon) creates a voltagesilicon) creates a voltage

Energy from sunlight knocks out electrons, creating aEnergy from sunlight knocks out electrons, creating a

electron and a hole in the junctionelectron and a hole in the junction Connecting both sides to an external circuit causesConnecting both sides to an external circuit causes

current to flowcurrent to flow

In essence, sunlight on a solar cell creates a smallIn essence, sunlight on a solar cell creates a smallbattery with voltages typically 0.5 v. DCbattery with voltages typically 0.5 v. DC

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Combining Solar CellsCombining Solar Cells

Solar cells can be electrically connected inSolar cells can be electrically connected in

series (voltages add) or in parallel (currentsseries (voltages add) or in parallel (currents

add) to give any desired voltage and current (oradd) to give any desired voltage and current (or

power) output since P = I x Vpower) output since P = I x V

Photovoltaic cells are typically sold in modulesPhotovoltaic cells are typically sold in modules

(or panels) of 12 volts with power outputs of 50(or panels) of 12 volts with power outputs of 50

to 100+ watts. These are then combined intoto 100+ watts. These are then combined intoarrays to give the desired power or watts.arrays to give the desired power or watts.

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Solar roof tileSolar roof tile

The solar roof tile consists of a unit of sixThe solar roof tile consists of a unit of six

individual tiles, which covers an area ofindividual tiles, which covers an area of

107cm X 30 cm.107cm X 30 cm.

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Solar Power SetupSolar Power Setup

The inverter DC toThe inverter DC to

AC electricityAC electricity

DC and AC safetyDC and AC safety

switchesswitches

Batteries (optionalBatteries (optionaldepending ondepending on

design)design)

Monitor (optionalMonitor (optional

but a good idea)but a good idea)

Ordinary electricalOrdinary electricalmeters work as netmeters work as net

metersmeters

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ENERGY EXTRACTIONENERGY EXTRACTION

The suns light produces energy that is collected byThe suns light produces energy that is collected by

SolarBlend roofing tiles.SolarBlend roofing tiles.

The energy collected is channeled to the inverter.The energy collected is channeled to the inverter.

The inverter changes the DC electricity to AC electricityThe inverter changes the DC electricity to AC electricityfor household use.for household use.

AC electricity not used by the house is fed into the grid.AC electricity not used by the house is fed into the grid.

Monitor system performance over the internet.Monitor system performance over the internet.

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Monthly Energy Savings, a CaliforniaMonthly Energy Savings, a California

Residential ExampleResidential ExampleMonthly electric bill $238.14

Monthly electricity use 956 kWh AC

Solar system size required toremove top most expensive tiers

5.3 kW DC

Monthly electricity productionfrom solar system

662 kWh AC

Monthly electricity consumption

from utility

294 kWh AC

New monthly electric bill $34.71

Monthly savings $203.43 (85%)

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Advantages and DisadvantagesAdvantages and Disadvantages

AdvantagesAdvantages

Inexhaustible fuel sourceInexhaustible fuel source

No pollutionNo pollution

Often an excellent supplement to other renewable sourcesOften an excellent supplement to other renewable sources

Versatile--is used for powering items as diverse as solar cars and satellitesVersatile--is used for powering items as diverse as solar cars and satellites

DisadvantagesDisadvantages

Very diffuse source means low energy production--large numbers of solarVery diffuse source means low energy production--large numbers of solar

panels (and thus large land areas) are required to produce useful amounts ofpanels (and thus large land areas) are required to produce useful amounts of

heat or electricityheat or electricity

Only areas of the world with lots of sunlight are suitable for solar powerOnly areas of the world with lots of sunlight are suitable for solar power

generationgeneration

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ConclusionConclusion

IIt is also believed that the value of a solar powered home cant is also believed that the value of a solar powered home canbe increased by 15% compared to the value of a house that isbe increased by 15% compared to the value of a house that isnot solar powered. Adding to this, solar power is a cleannot solar powered. Adding to this, solar power is a clean

source of energy that helps in making our environment muchsource of energy that helps in making our environment much

healthier.healthier.

The sun is the primary energy source for almost all energyThe sun is the primary energy source for almost all energy

flows on the planet. Its time we start using it.flows on the planet. Its time we start using it.

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THANK YOUTHANK YOU