BENEFITS AND ADVANTAGES OF SOLAR ENERGY

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Renewable EnergyRenewable Energy is a term that refers to energy sources that are renewable in nature, meaning that more and more is continuously generated, and for all practical purposes, that are virtually limitless in supply. Energy from our sun is one such example. Technically, the sunlight will fade in about 5 billion years, but for all practical purposes and human timescales, we will consider this a continuous and infinite resource. The sun isn't going to burn out any time soon.

Other renewable energy sources include wind and geothermal power. Wind power is generated by placing large windmills in windy areas, usually at high altitude to be maximally effective. Wind power, like solar power, is clean, but is also plagued by cost of setup and cost per kilowatt. Wind power may be unreliable in certain areas where the wind isn't strong year-round. Geothermal energy, a form of energy generated from the tectonic pressures and movements that heat the earth's crust, is used to boil steam and generate electricity.

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Non-Renewable EnergyNon-renewable energy is energy that is generated from non-renewable material reserves. These non-renewable resources are limited in supply that is to say that to be non-renewable a resource has to have a reasonably finite amount available for economically feasible extraction. We usually consider a resource non-renewable if it will non regenerate rapidly enough to meet our needs. Oil and coal are examples of non-renewable energy. Like all other fossil fuels, these non-renewable energy sources are created deep within the Earth, and cannot be replaced rapidly enough to meet the needs of any advanced civilization. Effectively, once we run out, we run out. We'll see miniscule amounts of oil and coal deposits build up, but it won't be for millions of years, eons of time, before our reserves are replaced. Nonrenewable sources of energy are used once, and afterwards are gone forever

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Benefits and advantages of solar energy

Solar energy is a renewable and inexhaustible source of powerful energy that is derived from the sun. According to astronomers, the sun will continue to shine for quite a number of million of years and therefore, you shall have access to unlimited and free source of power for a very long time, without having to worry about the depleting natural energy resources.

There is no fear of causing any kind of environmental damage or environmental pollution with solar power generation. This kind of energy production does not destroy the ozone layer. Solar energy is regarded as environment friendly, clean and safe.Solar energy is a renewable resource, The solar energy supply will last as long as the sun.

By switching over to solar energy, you can help to save your planet and further the cause of the wellbeing of the earth.

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Solar Energy Advantages

I. Saves you money

a. After the initial investment has been recovered, the energy from the sun is practically FREE.

b. Solar energy does not require any fuel. It's not affected by the supply and demand of fuel and is therefore not subjected to the ever-increasing price of gasoline.

c. The savings are immediate and for many years to come. d. The use of solar energy indirectly reduces health costs.

II. Environmentally friendly

a. Solar Energy is clean, renewable (unlike gas, oil and coal) and sustainable, helping to protect our environment

b. It does not pollute our air by releasing carbon dioxide, nitrogen oxide, sulphur dioxide or mercury into the atmosphere like many traditional forms of electrical generations does

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c. Therefore Solar Energy does not contribute to global warming, acid rain or smog.

d. By not using any fuel, Solar Energy does not contribute to the cost and problems of the recovery and transportation of fuel or the storage of radioactive waste

III. Independent/ semi-independent

a. A Solar Energy system can operate entirely independent, not requiring a connection to a power or gas grid at all. Systems can therefore be installed in remote locations (like holiday log cabins), making it more practical and cost-effective than the supply of utility electricity to a new site.

IV. Low/ no maintenance

a. Solar Energy systems are virtually maintenance free and will last for decades.

b. Once installed, there are no recurring costs c. They operate silently, have no moving parts, do not release offensive

smells and do not require you to add any fuel

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Solar Energy Disadvantages

a. The initial cost is the main disadvantage of installing a solar energy system, largely because of the high cost of the semi-conducting materials used in building one.

b. Solar panels require quite a large area for installation to achieve a good level of efficiency.

c. The efficiency of the system also relies on the location of the sun, although this problem can be overcome with the installation of certain components.

d. The production of solar energy is influenced by the presence of clouds or pollution in the air

e. Similarly, no solar energy will be produced during nighttime although a battery backup system and/or net metering will solve this problem for knowing more, as concern NET METERING follow link:www.dsireusa.org

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Usage of concave mirrors Using concave mirrors for producing thermal energy, in order to save money by reducing energy costs by a considerable amount.

Taking into consideration that boiling -- water is needed for many reasons in our everyday life,.Concave mirror can be used to heat water using solar energy.

The point F is the focus of the mirror. This is the point at which the rays o f light parallel to the axis converge after being reflected.

The point C is the centre of curvature of the mirror

Concave mirror

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HEATING WATER SYSTEM

water tube

Focus

concave mirror

platform

condenser

steam flow

water flow

cold water

hot water

sunbeam

(semi-filling)

Water heater (boiler)

At the focus of CM, the temperature is very high.

Platform must be movable-to move the CM and follow the sun movement ( rays of light parallel to the axis ) for maximal efficiency.

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UTILITY AND USE OF SOLAR ENERGY

Heating water and producing electric energy through solar cells.

There are two main forms of solar cells/panels (photovoltaic cells) in existence today, and these are;

"solar electricity panels“ “

&&

"solar hot water panels".

The two different technologies allow us to either generate electricity for our homes or to heat the water we use.

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PRODUCING ELECTRIC ENERGY THROUGH SOLAR PANELS

SOLAR PANELS-- (arrays of photovoltaic cells )

What is a solar electricity panel?

A solar panel ( also known as a photovoltaic panel or photovoltaic module ) is a device that converts photons of light from the Sun and converts them into an electric current.

Solar Panels are a form of active solar power, a term that describes how solar panels make use of the sun's energy: solar panels harvest sunlight and actively convert it to electricity. Solar Cells, or photovoltaic cells, are arranged in a grid-like pattern on the surface of the solar panel. These solar voltaic cells collect sunlight during the daylight hours and covert it into electricity

The heart of any solar power system is the solar panels,

Solar panels (arrays of photovoltaic cells) make use of renewable energy from the sun,

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View of solar panels/arrays)

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It is vital to install your solar panel so that it gets the most direct sun exposure - you want to make sure your solar panelis maximally effective year round.

To do this, there are several web-based solar resources to help you properly set up and install your solar panels by tracking the position of the sun in the sky over the course of the year.

Solar Panel Installation Tips12 volt 60 watt solar panel measure about 20 X 44 inches (5Amps)

Solar Panels --- are typically installed on rooftops, building tops, or stand-alone facilities.

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Position your solar panel in direct sunlightSolar Panels perform at optimum capacity when placed in direct sunlight. Try to position your photovoltaic array directly under the noontime sun for maximum efficiency from your photovoltaic unit.

Notice obstructions to sunlightRemove all items unnecessary items or trim branches that may be blocking sunlight to your solar unit. Trace the path of the sun in the sky to determine if an object is casting a shadow over your solar photovoltaic panels.

If this is the case, then the operating efficiency of your unit will undoubtedly suffer.

Mounting your Solar PanelSolar Panel Mounts are used to install photovoltaic solar panels. Solar panel mounts come in three main varieties: pole mounts, roof-ground mounts, and flush mounts. Using these mounts, you can install your solar panel against the side of a pole, on your roof, or even install them as a free-standing unit.

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A SOLLAR CELL ( A PHOTOVOLTATIC CELL )-

-Is an electrical component that converts light into electrical energy. The physical principle behind this is the photovoltaic effect.

Several solar cells can be electrically connected to form a solar panel.

The type of connection that is selected allows the electrical operating range (power and voltage) to be specifically tailored to the respective application of the solar panel.

Solar cells are made of various semiconductor materials.

Semiconductors are substances that can conduct electricity when heat or light is added, and they also act as electrical insulation at low temperatures

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How do Photovoltaics Work?

Photovoltaics is the direct conversion of light into electricity at the atomic level.

Some materials exhibit a property known as the photoelectric effect that causes them to absorb photons of light and release electrons.

When these free electrons are captured, an electric current results that can be used as electricity.

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A solar cell ( A PHOTOVOLTATIC CELL )

SOLAR PANELS (arrays of photovoltaic cells )

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Sunlight is composed of photons containing energy.

When photons strike a PV cell, their energy is transferred to an electron in the semiconductor material of the cell.

With this extra energy, the electron is then able to escape from its normal position in the atom creating a "hole", which will become part of a current in an electrical circuit.

A so-called p-n-junction is created on the barrier layer. The special feature of this barrier layer is that a strong electrical field is created locally.

If light falls onto the semiconductor free positive and negative charge carriers are created due to the photoelectrical effect.

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If this process takes place close to the p-n-junction, the local electrical field ensures that the positive and negative charge carriers are separated from each other. These move toward the outer electrodes ( contact fingers or reverse side contact ) and generate current; the solar cell therefore works similar to a battery. If the electrodes are then connected to an electrical consumer, current flows

A diode ( semi - conductor ) is formed when two layers of semiconductor materials are doped so that one will conduct negative carriers and the other positive carriers.

When photons fall on these layers they transfer energy and momentum to charge carriers, which increase their potential energy by an amount depending on the diode's material properties. Because of their electrical properties,

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n-type semiconductor

p-type semiconductor

p-n junction (electric field)

sunlight

front contact

back contact

+ + + + + + + + + + + + +

+

-DC- current

Solar cell -- construction

+

-

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PV modules produce direct current ( DC ) rather than alternating current ( AC ). In the simplest PV systems, DC current is used immediately in applications but where AC is required, an ,inverter is added to the system to convert DC into AC.Multiple solar panels are wired together to produce the: voltage, and, amperage, -- needed

DC system with batteries

PV array

Charge controller

Storage battery

12V - DC DC loads12V - DC

SOLAR SYSTEM

12V DC

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PV array

DC outlets

AC outlets

DC to AC inverter

Charge controller

Battery system

Solar system containing DC to AC invetror

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Utility-interactive system without batteries

Solar PV array

Grid Tie Inverter

AC Utility Meter

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Charge Controller:

A charge controller monitors the battery's state-of-charge to insure that when the battery needs charge-current it gets it, and also insures the battery isn't over-charged.

Connecting a solar panel to a battery without a regulator seriously risks damaging the battery and potentially causing a safety concern.

Charge controllers (or often called charge regulator) are rated based on the amount of amperage they can process from a solar array.

If a controller is rated at 20 amps it means that you can connect up to 20 amps of solar panel output current to this one controller

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Battery:The Deep Cycle batteries used are designed to be discharged and then re-charged hundreds or thousands of times.

Inverter:Inverter:An inverter is a device which changes DC power stored in a battery An inverter is a device which changes DC power stored in a battery to standard to standard 120/240 120/240 VAC electricity (also referred to as VAC electricity (also referred to as 110/220).110/220).

Most solar power systems generate DC current which is stored in Most solar power systems generate DC current which is stored in batteries.batteries. Nearly all Nearly all lightinglighting, , appliancesappliances, , motorsmotors, etc., are designed to use , etc., are designed to use ac power, so it takes an inverter to make the switch from battery-ac power, so it takes an inverter to make the switch from battery-stored DC to standard power (120 VAC, 60 Hz).stored DC to standard power (120 VAC, 60 Hz). In an inverter, direct current (DC) is switched back and forth to In an inverter, direct current (DC) is switched back and forth to produce alternating current (AC). Then it is transformed, filtered, produce alternating current (AC). Then it is transformed, filtered, stepped, etc . To get it to an acceptable output waveform. stepped, etc . To get it to an acceptable output waveform.

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PV MODULES IN SERIES AND PARALLEL

Photovoltaic modules and batteries are a system’s building blocks.

While each module or battery has a rated voltage or amperage.

They can as well be wired together to obtain a desired system voltage and amperage.

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SERIES CIRCUITS

When voltage sources are connected in series the voltage increases.Series wiring does not increase the amperage produced.

Rules concerning series circuits:When loads or sources are wired in series-voltages are additive. o Current is equal through all parts of the circuit.

o In a series circuit batteries are connected end -to-end or positive ( + ) to negative ( - ).

o Batteries placed in series will provide a total voltage equal to the sum of each individual battery voltage.

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PV MODULES IN SERIES

12V DC3A

12V DC3A

24Volts at 3Amps

Problem:When two 12V DC, 3Amps modules are wired in series

What is the resulting system voltage and current?

Solution:

V-DC= 12V+12V = 24V3Amps system

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PARALLEL CIRCUIT

When loads or sources are wired in parallel, currents are additive and voltage is equal through all parts of circuit.

To increase the amperage of a system the voltage sources must be wired in parallel

Parallel wiring is from positive ( + ) to positive ( + ) and negative ( - ) to negative ( - )

Batteries are as well often connected in parallel to increase the total Amps, which increase the storage capacity and prolongs the operating time.

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12V DC3A

12V DC3A 12 Volts

at 6 Amps

PV Modules in parallel

this figure shows PV modules wired in parallel to get 12V,6Amps system.

NOTICE that parallel wiring increases the current produced and does not increase voltage.

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PV MODULES IN SERIES AND PARALLEL

Systems may use a mix of series and parallel wiring to obtain required voltages and amperages

12V DC3A

12V DC3A

12V DC3A

12V DC3A

24 Voltsat 6 Amps

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How much would a solar system cost?

What does count is: Where you are in the world. How much sun you get per day. How much you use

….Where you are affects how much yearly average sun you get. Solar panels make power from the sun, so no sun, no power.

In the US that can vary from a yearly average of about 4 to 6 hours per day. You will usually get more in summer, less in winter.

How much sun you get also depends on where the panels are, how much - if any – shade they might get during the day, and what angle and direction you can mount them at.

To work best, solar panels should be aimed South,

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Factors of Solar Cell CostsSolar panels of the same size may produce variable amounts of electricity - this discrepancy arises from variations in the functioning age of the solar cells, the quality of the solar cells, and with what technology they were produced. Early solar cells, for example, are not quite as efficient as modern solar cells,

As another example, two identical solar cells are purchased. One is left in storage and the other has been in use for three years. Solar panels have an effective lifespan of about 20 to 25 years, and their value and wattage output decrease steadily over time.

The solar cell that has been in storage will be more valuable than one that has been actively converting sunlight to electricity for a long time. In summary, although two solar panels may seem identical, there are a number of other factors you need to take into consideration. Quality, age, and technology all play a role in the cost of the solar cell

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How to figure the cost for 100% solar power

First, take number of KWH shown on your bill. Divide that by 30. That gives you your average daily usage. So if you use 700 KWH, that is 23.3 KWH per day.

Take that number. Divide it by the number of full sun hours you get per day on a yearly average. Multiply it by 1.15. That will give you a pretty close estimate of how many watts of solar panel you need. So if you get 5 hours per day, divide 23.3 by 5 - that gives you 4.66 KW, or 4,666 watts. Multiply that by 1.15, which gives you 5,360 watts of solar panel needed.

Average installed cost of solar electric if you do it yourself is around $7 per watt. So that system will cost you around $37,500.

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A short introduction to: Solar Hot Water Panels

The use of solar panels to heat water is becoming increasingly popular around the world due to the energy and money saving associated with this method.

Solar energy panels can use the sun’s energy to heat water for sanitary use at home or for pools and hot tubs.

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Now imagine if you could combine not only a solar panel hot water heating system, but also an average solar electricity system. This would save a heap on energy and electricity bills.

The combination of a solar hot water panel with other renewable energy technologies, such as solar panels, or a home wind turbine can work quite well together in providing a source of cheap, clean, and renewable energy for our homes.

.A good solar hot water panel system is able to provide an average household with around a third of its annual hot water supply. While this may not sound much, it can reduce energy costs by a considerable amount.

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