Solar photovotaic system

“SOLAR PHOTOVOTAIC SYSTEM“ Practical Training Report

Submitted

For the award of the degree of

Polytechnic

In Department of Electrical Engineering

Board of Technical Education Rajasthan, Jodhpur

Submitted To:- Guided By:- Submitted By:-

Mr. VIRENDRA SWAMI Mr. VIRENDER SWAMI MAYANK PATEL

(EE2014016/210)

DEPARTMENT OF ELECTRICAL ENGINEERING

Maharishi Arvind College of Engineering and Research center, Sirsi Road, Jaipur

College of Engineering and Research Centre

OCTOBER, 2016

ACKNOWLEDGEMENT

Words cannot suffice to even being to show the gratitude we owe to the people who guided

me in this Practical Training Seminar.

First of all I would like to thank my supervisor “MR. VIRENDRA SWAMI” Department of

Electrical Engineering, Maharishi Arvind College of Engineering and Research Center,

Jaipur Of whom I am highly indebted for their valuable technical guidance and moral

support during the practical training seminar. This seminar could not have been possible

without their generous help invaluable suggestions, initiative & keep interest in this

seminar.

I would also like to thank “MR. R.PANNEERSELVEM” principle director MSME-Technology

Development Centre, Agra. For there support in practical training held in Jaipur.

Mayank Patel

(EE2014016/210)

CONTENT

I. Overview of Renewable Energy

II. Schematic block diagram of SPV system

III. Basics of SPV Arrays

IV. Benefits of SPV Systems

V. Arrays in parallel

VI. Arrays in series

VII. Batteries

VIII. Inverters

IX. Controllers

X. Color code of wires used in PV systems

XI. Basics of system Sizing

XII. Solar lanterns

XIII. SPV home lightning system

XIV. SPV street lightning system

XV. conclusion

OVERVIEW OF RENEWABLE ENERGY

Global solar installations will reach 64.7 GW in 2016. A clean energy communications and research firm based in Texas. “ The top three countries will be CHINA, U.S., AND JAPAN and they will account for two thirds of the global markets”.

Although China is expected to continue leading the global PV market the U.S. will show the most robust growth in 2016. Due to the anticipation of the federal Investment Tax Credit (ITC) expiration. Which developers and EPC has already factored in to their business plans for 2016, prior to the five year extension received at the end of 2015.

In 2016, The U.S. is set to overtake Japan as the second largest solar market, exceeding the much anticipated 10 GW mark. Another notable shift will see India move up to the no. 4 position. Pushing down the former European leaders, U.K. and Germany

BASICS OF SPV ARRAYS

INTRODUCTION:-

“PHOTOVOLTAIC” refers to the creation of voltage from light and is often abbreviated as

just “PV”. A more common term for photovoltaic cell is “solar cell”, although the cell work

with any kind of light and not just sun light.

Solar cell is a converter. It changes light energy into electrical energy. A does not store any energy. So, when the source of light (typically the sun) is removed, there is no electrical current from the cell. The conversion process occurs instantly whenever there is the light falling on the surface of the cell. The output of the cell is proportional to the input light, the more light the greater electrical output.

MATERIALS USED FOR SOLAR CELLS

There are many materials used to make Solar cells, but the most common is the Silicon. Silicon is second most abundant Element in the earth’s crust it is therefore Non-toxic and safe. This is the same silicon That is used to make computer chips! Some Of the processing steps involved in making Solar cell are same as making computer

SOLAR CELL

People often says solar cells work by “magic”

because there is nothing moving, the result is

instantaneous, and no fuel is apparently needed!

The basic process by which solar cells convert

sunlight into electricity can seem “magical”, but

actually it is simple!

Chips.

PRINCIPLE OF ELECTRICITY GENERATION

When light shines on the solar cell the energy of the light actually penetrates into the solar

cells, and on the random basis, “knocks” negatively charged electrons loose from their

silicon atoms. To understand this, you can think of light as being made of billions of energy

particles called “photons”. The incoming photon acts much like billiard balls, only they are

made of pure energy! When they collide with an atom, the whole atom is energized, and an

electron Is ejected or ionized from the atom.

The freed electron now has extra potential energy, and this is what we call “voltage or

electrical pressure”, but the problem how to get the freed electron out of the solar cell, this

is accomplished by creating an internal electrostatic field near the front surface of cell

during manufacturing.

ELECTRIC CURRENT IS SIMILLAR TO WATER FLOW

It is often help full to give analogy to water flow- ing. You imagine that a water pump connected to a circuit of pipes that are already full of water. The pipe circuit also include some sort of load like a water wheel so, when the pump is turned on, water flows almost simultaneously thro ughout the while system. As a result, the water flows on to the load like the water wheel, where is pressure and flow allow useful work to be done. All the water is then captured and flows again through pipes back to the pump. The pump continues to push new water to the loads through the pipes. The pump is the solar cell, the pipes are the wire connecting the cell to an electrical load and

back to the cell, and the water in the pipes is like the electron already present in the wire.

SILICON PHOTOVOLTAIC CELL TYPE

Single Crystal Silicon

Polycrystalline Silicon (Multi crystal silicon)

Ribbon Silicon

Amorphous Silicon (thin film silicon)

The solar cell never “runs out” of

electrons. It only needs continuous

input of “fuel” in the form of light

energy to keep running .

• Most photovoltaic cells are single crystal types.

• The cells have uniform colour usually blue or black.

• Silicon rocks are melted and then slowly regrown.

• The back of the cell is covered by a full grid of printed metal.

SINGLE CRYSTAL SILICON

• This is also known as "multi-cryatal silicon".

• These cells are manufactured and operated in a similar manner.

• In this liquid silicon is allowed to cool into a block.

• This usually results in slightly lower efficiency.

POLYCERSTALLINE SILICON

• These cells operate in the same way that of first two.

• Liquid silicon is slowly off and cools in to a flat thin shape.

• and is further scribed and broken in to rectangular dells

RIBBON SILICON

• These are also known as "thin film silicon".

• Amorphous silicon has no distinct cryatal sturucture.

• It is some times abbriviated "aSi".

• They are variety of colours.

AMORPHOUS SILICON

CELL, MODULE, PANEL AND ARRAY

It is important, that you should be clear on the difference between these terms, especially between “module” and “panel”. A cell is basic building block of a manufacturer of solar modules. The fundamental physics of the material used determines the voltage of a cell and the size determin e the current. This is the smallest unit in solar PV system. A module is really a basic building for real world remote power system. It is the collections of cells interconnected by usually that wire, and includes encapsulations to protect the cells and interconnecting wire from corrosion and impact. It usually includes a frame to allow easy mountings. A panel is a collection of modules physically and electrically grouped together on a structure. This would be a building block for larger power systems. Usually the modules are wired together on the panel to give the final system voltage and the panels are wired together through field junction boxes and then on to the system controls and batteries. An array is a full collection of all solar photovoltaic generators. Sometimes an array is so larger that is grouped in to SUBARRAYS for easier installations and power management. An array can be small as one module and as large as 1,00,000 modules.

BENEFITS OF SPV SYSTEMS

KEY BENEFITS OF SPV SYSTEMS

Energy independence. “Fuel” is already delivered free everywhere. Minimum maintenance. Maximum reliability. Generate the power where you need it. Easy expandable.

ENERGY INDEPENDENCE One of the most attractive benefits you get out of SPV systems is that “energy independence” i.e. the ability to create your own electrical power, independent of fossil fuel supplies or utility connections. FUEL IS ALREADY DELIVERED AND EXISTS EVERYWHERE In a sense, you do need sunlight as a fuel, but that is already delivered free all over the planet’s surface other conventional generation methods require access to a site for fuel deliveries. This may limit the choice of suitable sites. MINIMUM MAINTENANCE Solar systems typically require very minimum maintenance because there are a very few moving parts. Compared to diesel powered systems or any other renewable sources such as wind generators or hydro generators. They also requires costly repairs or regular maintenance of moving parts. MAXIMUM RELIABILITY This perhaps the primary advantage what you get out of SPV when compared to any other form of electrical power generation because there are typically few or no moving parts, the ultimate reliability of PV power system in the real world is quite high.

GENERATE THE POWER WHERE YOU NEED IT You can think differentially about SPV systems for your applications. You need not always have to consider a central large generator for all your current demand. You can generate the power at various sites, such as at each classroom or each house. EASILY EXPANDABLE As you know that PV power generators are modular by design. So, you can add more power to an existing array easily. You can add old modules to the new once with out any penalty you can purchase and install any time to meet your current needs. And as demand grows you can add more modules later.

ARRAYS IN PARALLES

When wiring solar panels in parallel, the amperage (current) is additive,

but the voltage remains the same.

E.g. If you had 3 solar panels in parallel and each was rated at 6 volts and 3

amps, the entire array would be 6 volts and 9 amps.

The connection is very easy, just connect positive terminal of one panel to the

positive terminal of the other and negative terminal of one panel to the

negative terminal of second panel.

This connection of arrays is used to increase the current rating.

ARRAYS IN SERIES

When wiring solar panels in series, the voltage is additive, but the current remains the same.

E.g. If you had 3 solar panels in parallel and each was rated at 5v, 7v and 9v volts and 3 amps, the entire array would be 21 volts and 3 amps.

The connection is very easy, just connect positive terminal of one panel to the negative terminal of the other.

This type of connection is used to increase voltage rating.

BATTERIES

The understood component of the SPV systems is batteries. These are of two types

primary and secondary. Primary are non-rechargeable and secondary are rechargeable.

Primary batteries are not used in SPV systems because they cannot be recharged.

Secondary batteries can store and deliver electrical energy, and can also be recharged

by passing a current through it in an opposite direction. Therefore, secondary batteries

are the only option in SPV systems.

PRIMARY FUNCTIONS OF BATTERIES

Energy storage capacity.

Voltage and current stabilization.

ENERGY STORAGE CAPACITY

This is the capacity to store electrical energy when it is produced by the PV array and to

supply energy to electrical load as needed or on demand. A stand a lone PV system has

sufficient battery storage capacity to operate the electrical loads directly from the battery.

VOLTAGE AND CURRENT STABILIZATION

This is the ability to supply power to electrical loads at stable voltages and currents, by

acting as a buffer between the PV array and loads, a battery can also stabilize the voltage

and current supply to electrical loads in which the load power requirement oscillates or

varies with respect to time.

BASIC TERMINOLOGY

The cell is the basic electrochemical unit in a battery, consisting of a set of positive and

negative plates divided by separators immersed in an electrolyte solution and enclosed in a

case. In a typical lead acid battery each has nominal voltage about 2.1 volts so there are six

series of cell in a nominal 12V battery.

The electrolyte is a conducting medium which allows the flow of current through ionic

transfer or the transfer of electrons between the plates in the battery. In a lead acid battery

the electrolyte is a diluted sulphuric acid solution, either in liquid form, gelled, or in glass

mats.

The grid (in a battery) is typically a lead alloy frame work that supports the active material

on the battery plate, which also conducts current

Alloying elements such as antimony and calcium

Are often used to strengthen the lead grids and

Have characteristic effect on battery performance

Such as cycle performance and gassing.

The plate is a grid wire, active material pasted on

It. It is called electrode. There are generally a number of positive and negative plates in

each battery cells, typically connected in parallel at a bus bar ore inter-cell connector at the

top of the plates, it is made by applying a mixture of lead oxide, sulphuric acid, fibers and

water on the grid.

A separator is a porous, insulating divider between the positive and the negative plates in

a battery used to keep the plates from coming into electrical contact and short-cutting and

which also allows the flow of electrolyte and ions between the positive and negative plates

they are made from microporus rubber, plastic or glass-wool mats.

An element is defined as a stack of positive and negative plate groups and separators

assembled together with plate straps interconnecting the positive and negative plates in a

lead acid battery an element will generate nominal 2V.

Terminal posts are the external positive and negative electrical connections to a battery. A

battery is connected in a PV system and to electrical loads at the terminal posts. In a lead

acid battery the posts are generally lead or a lead alloy. Terminal may require p eriodic

cleaning.

Note!

Batteries are designed for different

applications. Do not use a car battery in a

PV system

BATTERY CAPACITY

Battery capacity is a measure of a battery’s ability to store or deliver electrical energy,

commonly expressed in units of ampere-hours. An ampere-hour is equal to the transfer of

one ampere over one hour. For e.g., a battery which delivers 5 amps for 20 hours is said to

have delivered 100 ampere-hour.

The capacity of the battery depends on several constructional factors like the quantity of

active material, the no. and physical dimensions of the plates, and the electrolyte specific

gravity.

Battery capacity also depends on the operational factors like the discharge rate, depth of

discharge, cut-off voltage, temperature and cycle history of the battery.

NOTE! PV systems need deep cycling batteries.

𝑏𝑎𝑡𝑡𝑒𝑟𝑦 𝑐𝑎𝑝𝑎𝑐𝑖𝑡𝑦 = 𝑙𝑜𝑎𝑑 (𝑎𝑚𝑝𝑒𝑟𝑒) × 𝑡𝑖𝑚𝑒(ℎ𝑜𝑢𝑟)

INVERTERS

A solar inverter converts the variable (DC) output of PV solar panel in to a utility frequency

(AC) that can be fed in to a commercial electrical grid or used by a local off-grid electrical

network. These are also known as converter or PV inverters.

TYPES OF INVERTERS (50 Hz)

SQUARE WAVE INVERTERS

As the current moves through the primary side of the transformer, the polarity is reversed

100 times each second. As the results, the current emerging from the secondary side is

alternating, going through 50 complete cycles per second. The simplest inverters de little

else beyond this operation. As a consequence the AC output is also very simple. The

direction of current flow through the primary side of the transformer is changed very

rapidly. So, the waveform on the secondary side is “square”.

These type of inverters are least expensive but also least efficient to!

QUASI-SINE WAVE INVERTERS

These type of inverters are named “quasi sine wave” as the output is not a true sine wave

but it only resembles or get closer to sine wave. By adjusting the off time it is possible to

eliminate third harmonics completely. Many variations exist in these type of inverters.

MODULATED PULSE-WIDTH WAVEFORM INVERTERS

Another way to approximate a sine wave uses high switching speed (20KHz). both

directions of DC input to the transformer are turned on and off r apidly in a particular

pattern. the resulting wave forms looks like a picket fence. The width of the “ON” picket

fence gets colder to a peak of a sine wave, the picket gets wider and wider. Output filtering

is used to reconstruct the sinusoidal wave shape.

SINE WAVE INVERTERS

True sine wave inverters can be built, however these are large and expensive. they can be

very inefficient, some times operating at only 30-40%. This will of course mean that the PV

array and battery must be over sized.

Newer solid sine wave inverters are available which operates at efficiencies of about 90%

or better depending on the size of the load. Cost of these types is much above the costs of

less sophisticated inverters.

SYNCHRONOUS INVERTERS

PV systems connected to the utility grid can use synchronous inverters. These are

sometimes called “line-commutated”. These inverters use the wave forms the utility AC

lines as a pattern to convert photovoltaic DC into AC.

CHARGE CONTROLLERS

The charge controllers is the energy manager in stand alone SPV systems, which

ensures that the battery is cycled under the conditions which do not reduce its ability to

deliver its rated capacity over its expected lifeline.

Whenever batteries are included in the system, the additional facility must be built in,

that will protect against overuse, the protection is given by charge controllers.

These are also known as charge regulators.

PRIMARY FUNCTIONS

The primary function of the charge controllers in a stand alone SPV system is to protect

the battery from over-charge or over-discharge. Any system that has any un predictable

loads, user interventions, optimized or undersized battery storage, or any

characteristics that would allow excessive battery over charging or over discharging

required a charge controller, lack of controller may result in shortened battery lifetime

and decrease load availability.

PREVENTION OF BATTERY OVER CHARGING

Current from the array will flow into a battery propositional to the irradiance. Whether

the battery needs charging or not. If the battery is nearly full already, it will be over

charged. The voltage will rise, gassing will begin, electrolyte will be lost, internal

heating will occur and battery life will be reduced. if left uncontrolled, the battery could

loose almost all its electrolyte and be permanently damaged and the loads could not

fails. Charge controllers prevent excessive charging by interrupting the current flow

from the array into the battery.

PREVENTION OF BATTERY OVER DISCHARGING

If you leave the loads ON too long, the battery can be over discharged. The reaction of

lead and lead oxide will proceed too close to the lead grid material and weaken the

bond. This can result in greater resistance and heat generation, accelerating the loss of

life. Some shallow cycling types of batteries are very difficult to recharge once they have

been severely discharged, especially with the slow charge rates typical for remote PV

systems. If batteries are too deeply discharged, the voltage falls below the operating

range of the loads and the load will fail.

Over discharge protection usually consist of a low voltage alarm or a disconnect relay

built into a charge control system or a circuit that operates an external disconnect.

ADDITIONAL FUNCTIONS THAT CAN BE INTEGRATED

Besides controlling the charge of the battery, the charge regulator of full control

centre for most of the system wiring connections.

A small cabin lighting system for example can have the light circuit connected to

the load terminal on the charge regulator.

A fuse for array and battery protection can be included in the regulator.

Larger systems can have circuit breakers for separate load circuits enclosed in

the control center housing.

Array, battery, inverter, and DC load circuit can all be connected within the

housing.

Fusing lightning protection and grounding can also be included as the function

of control center.

PV array

Current

regulator

Battery

Load

Simple series configuration of charge controllers

COLOR CODE OF WIRES USED IN PV SYSTEM

The color coding of wire makes wiring easier and is used to designate its function. It

also minimizes the possibility that incorrect connections will be made. For AC house

wiring in the US, white or grey is always used for neutral or main system grounds. The

hot wires can be black, red, blue, or yellow. Black is the most common, but in cables

with two hot wires, black and red are used.

In PV systems, the NEC (national electrical code) specifies that in a DC circuit the

system grounded conductor be white. There is no convention designating the color of

ungrounded conductors but typically red or black are used. Green or green with yellow

stripes is used for the equipment ground.

Wire AC (below 600 volts) DC (below 600 volts)

Neutral or Ground White or Gray White

Hot (high side) Black, Red, Blue or Yellow Black or Red

Equipment ground or grounding

Green or Green with yellow stripes

Green or Green with yellow stripes

BASICS OF SYSTEM SIZING

You think of the load as being supplied by the energy storing device. Usually the battery

and your PV system as the battery charger now it is essential for you to size the system i.e.

to calculate the number of PV modules and batteries needed. To reliably operate loads

through out a typical year.

ARRAY AND BATTERY SIZING PRINCIPLES

ARRAY SIZING

The solar array is sized to replace the load on a daily basis, based on average weather

conditions. The average days and above average days. so, array and battery must work

together.

The proper approach to array sizing is to calculate the array needed during the worst

season of the year. This will meant that the battery will be fully recharged even during the

worst season, and certainly during all the rest of the year. This will reduce the sulphation

that might occur on the battery plates, and lead to long system operating life and low

maintenance cost over time.

BATTERY SIZING

The battery bank is sized to operate the loads during a long sequence of below average

isolation days. You can think of the battery as being “full of charge” during a below average

day, the array cannot supply all the ampere-hour (Ah) of charge needed to replace what the

load draws from the battery.

Maximum percentage usable

Battery type percentage

Deep cycling up to 80%

Shallow cycling up to 50%

𝑏𝑎𝑡𝑡𝑒𝑟𝑦 𝑐𝑎𝑝𝑎𝑐𝑖𝑡𝑦 =𝑛𝑜. 𝑜𝑓 𝑑𝑎𝑦𝑠 𝑟𝑒𝑠𝑒𝑟𝑣𝑒𝑑 × 𝑑𝑎𝑖𝑙𝑦 𝑙𝑜𝑎𝑑

𝑀𝑎𝑥𝑖𝑚𝑢𝑚 % 𝑢𝑠𝑎𝑏𝑙𝑒

Determine the load (energy not power).

Calculate the battery size, if one is needed.

Calculate the no. of PV modules required.

Assess the need for any back-up energy or flexibility for load growth.

A simple Example:

Consider a sample system for a 12 volt street light. The light is 30 watt and will expected to

run all night year round. As you know, low wattage, high efficiency lights are the types that

make sense for SPV systems.

First step: design for worst case

Consider the worst case conditions. The load is greatest in the winters, which is the worst

case for the load and also the worst case for the resource.

For this example, we assume that the lights are needed for sixteen hours a day in winter.

Therefore, the total energy requirement is 30 watts x 16 hours = 480 watt-hours a day.

Second step: apply a safety/losses factor

At this point, you multiply the actual load by 1.5 to create an adjusted load value to account

for several factors are system efficiencies, including wiring and interconnection s losses as

well as the efficiency of the battery charging and discharging cycles.

𝑁𝑜. 𝑜𝑓 𝑠𝑒𝑟𝑖𝑒𝑠 𝐵𝑎𝑡𝑡𝑒𝑟𝑖𝑒𝑠 = 𝑙𝑜𝑎𝑑 𝑛𝑜𝑚𝑖𝑛𝑎𝑙 𝑣𝑜𝑙𝑡𝑎𝑔𝑒

𝑏𝑎𝑡𝑡𝑒𝑟𝑦 𝑛𝑜𝑚𝑖𝑛𝑎𝑙 𝑣𝑜𝑙𝑡𝑎𝑔𝑒

𝑑𝑎𝑖𝑙𝑦 𝑙𝑜𝑎𝑑 = 𝑙𝑜𝑎𝑑 𝑤𝑎𝑡𝑡𝑠 × ℎ𝑜𝑢𝑟𝑠

𝑎𝑑𝑗𝑢𝑠𝑡𝑒𝑑 𝑙𝑜𝑎𝑑 = 𝑎𝑐𝑡𝑢𝑎𝑙 𝑑𝑎𝑖𝑙𝑦 𝑙𝑜𝑎𝑑 × 1.5

Third step: determine hours of available sunlight

Most solar resource data are given in terms of energy per surface area per day. No matter

the original unit is used. Because of a few convenient factors, this can be read directly as

“sun-hours a day”.

Fourth step: determine the size of the array.

The size of the array is determined by the daily energy requirement divided by the sun-

hours a day. For your system the size of the array is 720 divided by 4.6 or 156 watts. This is

the size of the array. If use 35 watt modules must be used, then you will wind up 175 watts.

Remember, when converting calculated array to actual modules, always round up.

Fifth step: determine the size of the battery.

A conservative design will save the deep cycling capability of batteries for occasional duty

and keep the duty discharge at only about 20% of capacity. For battery sizing an

adjustment factor of about 1.5 times is also applied to the actual daily load to arrive at an

adjusted load.

𝑎𝑟𝑟𝑎𝑦 𝑠𝑖𝑧𝑒 =𝑎𝑑𝑗𝑢𝑠𝑡𝑒𝑑 𝑙𝑜𝑎𝑑

4.6 ℎ𝑜𝑢𝑟𝑠

𝑏𝑎𝑡𝑡𝑒𝑟𝑦 𝑠𝑖𝑧𝑒 = 𝑎𝑑𝑗𝑢𝑠𝑡𝑒𝑑 𝑙𝑜𝑎𝑑 × 5

SOLAR LANTERNS

CFL BASED:

A solar photovoltaic (SPV) lantern (solar lantern) is a lighting system consisting of a lamp,

battery and electronics, all placed in a suitable housing made of metal or plastic or fiber

glass, and a PV module. Electricity generated by the PV module charges the battery. The

lantern is portable lighting device suitable for either indoor or outdoor lighting. Covering a

full range of 360°.

DUTY CYCLE:

The solar lantern should provide a minimum of 3-4 hours of lighting per day. The actual

duration of lighting could vary depending on the location and season.

SPV MODULE:

The PV module to be used with the Solar lantern must have a minimum of 10 Wp at a load

voltage of 16.40 ±0.2 V under the standard test conditions (STC) of measurement.. the

module efficiency should not be less than 12%.

BATTERY:

Sealed maintenance free lead acid battery. The battery capacity should be a minimum of 7.0

AH at 12 V at 𝐶 20⁄ discharge rate.

ELECTRONICS:

The inverter should be of quasi-sine wave/sine wave type with a crest factor less than 1.7

and the frequency in the range of 20-35 kHz.

LAMP:

The lamp should be a 7watt compact fluorescent lamp (CFL) with 4 pins only along with

proper pre-heating circuit.

INDICATORS:

The system should have two indicators on green and other one is red. The green should

indicate the charging under progress and should glow only when the charging is taking

place. It should stop glowing when the battery is fully charged. Red should indicate the

battery load cut-off condition.

LED BASED:

A solar photovoltaic (SPV) lantern (solar lantern) is a lighting system consisting of a W -

LED’s, battery and electronics, all placed in a suitable housing made of metal or plastic or

fiber glass, and a PV module. Electricity generated by the PV module charges the battery.

The lantern is portable lighting device suitable for either indoor or outdoor lighting. White

LED is a solid state device which emits light when an electric current passes thr ough it.

DUTY CYCLE:

The solar lantern should provide a minimum of 3-4 hours of lighting per day. The actual

duration of lighting could vary depending on the location and season.

SPV MODULE:

The PV module to be used with the Solar lantern must have a minimum of 3 to 5 Wp under

the standard test conditions (STC) of measurement.

BATTERY:

Sealed maintenance free lead acid battery or NiMH or lithium ion. The battery capacity

should be a minimum of 7.0 AH at 12 V at 𝐶 20⁄ discharge rate.

LIGHT SOURCE:

The LED should be a 5500°k to 6500°k light emitting diode (LED).

INDICATOR:





SPV HOME LIGHTING SYSTEM

A solar home lighting system (SHS), converts solar energy into electrical energy and

provides a comfortable level of illumination in one or more rooms of a house. There are

several (SHS) modles featuring one, two or three CFL’s. the system could also be used to

run a small DC fan or a 12 V DC television along with the CFL’s.

DUTY CYCLE:

All the models of solar home lighting systems should be designed to operate for 3-4 hours

daily. The actual duration of lighting could vary depending on the location and season.

DEFFERENT MODELS OF SPV HOME LIGHTING SYSTEM

MODEL-1 (1 LIGHT)

PV module one 18 Wp under STC.

Lamps one CFL (9W or 11W).

Battery one 12V,20 AH lead acid, tubuler positive plate flodded electrolyte or gell type.

Other components control electronics, module mounting hardware, battery box,

interconnecting wires/cables, switches.

MODEL-2 (2 LIGHTS)


Lamps two CFL (9W or 11W).




MODEL-3 (2 LIGHTS AND 1 FAN)


Lamps two CFL (9W or 11W).

Fan one DC fan (with wattage less than 20 W).




MODEL-4(4 LIGHTS)


Lamps four CFL (9W or 11W).




NOTES!

All models should have a socket to provide power for a 12 V DC TV set which can be

purchased separately.

A small white LED could be provided as an optional feature with an independent

switch.

SPV STREET LIGHTING SYSTEM

A stand alone SPV street lighting system is an outdoor lighting used for illuminating an

street or an open area. It consist of PV modules, CFL’s, lead acid battery, control

electronics, inter connecting wires/cables, module mounting pole including hardware and

battery box. The CFL is fixed inside the reflecting case (luminary) which is mounted on the

pole. The PV module is placed at the top of the pole at an angle to maximize incident solar

radiation. A battery is placed In a box attached to the pole. The module is mounted facing

south as it receives solar radiations throughout the day without any shadow falling on it.

DUTY CYCLE:

The system should automatically switch is ON at dusk, operate throughout the night and

automatically switch is OFF at dawn.

PV MOUDLE’s:

Both crystalline and thin film technology modules are allowed in the system. The module

should have a certificate of testing conforming to IEC 61215 edition II /BIS 14286 or IEC

61646 for crystalline and thin film PV modules respectively.

The operating voltage corresponding to the power output mentioned above should be

16.4 ± 0.2 V.

BATTERY:

Battery lead acid, tubuler positive plate flodded electrolyte or gell type. The battery will

have a minimumrating of 12 V, 75 Ah (at 𝐶 10⁄ discharge rate).

LAMP:

The lamp should be 11 watt compact fluorecent lamp 4 pins along with proper pre heating

circuit.

ELECTRONICS:

The inverter should be of quasi-sine wave/sine wave type with a crest factor less than 1.7

and the frequency in the range of 20-35 kHz. The total electronic efficiency should be not

less than 85%. The ideal current consumption not be more than 10 mA.

OTHER FEATURES:





CONCLUSION

This practical training enhances our technical knowledge. We get to know about different

technologies, items, and materials used in SPV system. And their daily use.

We get to know that how they are manufactured and rated also studied their functions and

concept behind them. This will also help us in our future and in our placements also. It was

a very intresting and knowledgement training and it was a great opportunity to be a part of

it.

Solar photovotaic system

Career