SOLAR PV
SYSTEMS
A BASIC INTRODUCTION AND OVERVIEW
Presented By: Stephen Jones

INTRODUCTION TO SOLAR PV SYSTEMS
• What is a solar system
• How Solar Works
• Components of a Solar System
• Types of Solar System
• Designing the System
• Safety
• PV Wiring
• Battery Wiring
• Wiring the System
• Glossory
• Practical

WHAT IS A SOLAR PV SYSTEM?
• A solar PV System is a system which captures the sun’s energy
and converts it into useful energy i.e. electricity
• PV: Photovoltaic

HOW SOLAR WORKS
• Light hits the solar panels with photons (particles of sunlight).
The solar panel converts those photons into electrons; direct
current.
• Electrons then flow through a conductor to the various device.
• The material responsible for doing this conversion is call a cell.

COMPONENTS OF A PV SOLAR SYSTEM
• A PV Solar system typically consists of 4 basic
components.
• PV Array
• Batteries
• Inverter
• Charge Controller

COMPONENTS OF A PV SOLAR SYSTEM:
PV ARRAY (SOLAR PANELS)
• The PV Array: Electricity is generated by solar cells. Individual
solar cells are grouped together into a solar “panel” or
“module”. Then, several solar modules are grouped together to
form a PV array.

FACTORS AFFECTING SOLAR
PANELS
• Temperature
• Shading
• Dust

TYPES OF SOLAR PANELS
• Single-crystal or Mono-crystalline Silicon
• Polycrystalline or Multi-crystalline Silicon

MONOCRYSTALLINE SILICON
MODULES
 Most efficient
commercially
available module
 Most expensive to

POLYCRYSTALLINE SILICON
MODULES
 Less expensive to
make than single
crystalline modules
 Cells slightly less
efficient than a single
crystalline

PANEL
MOUNTING
• Racking

COMPONENTS OF A PV SOLAR SYSTEM:
BATTERIES
• The batteries in a solar solar PV system stores the energy
produced from the pv array and delivers it o the inverter which
supplies the load.
• A group of batteries in a solar pv system is called a battery
bank.

BATTERY
CARE
• Battery must not be discharged more than 50%
• Charge controllers must be set to correct presets depending on
type of battery and battery requirements.
• Battery should be kept topped up with distilled water.

PRECAUTION
S
Never Add Acid
Under-watering: electrolyte level must never be dropped below
the top of the plates
Over-Watering: Diluted electrolytes, Add water only when
battery is fully charged
Under-charging: Forms sulphate on battery plates
Over-charging: corrosion of positive plates, excess water
consumption

BATTERY CHARGING
• There are three basic charging stages
Bulk Charge: delivers maximum charging current to the battery till it reaches
80%.
Absorption stage: for the remaining 20% of charge Voltage remains constant
and current gradually decrees until the battery is fully charged.
Equalization Stage: Typical peak voltage is delivered to the battery *15 to
16volts in a 12volts system) and is held fixed for a limited period of time
typically 1-2hrs(depending on manufacturer’s preset).
Float Charge: Otherwise called maintenance or trickle charge is the stage
where the voltage is reduced to a lower level after full charge, this extends
battery life. It’s purpose is to keep the charged battery from discharging.

CAR BATTERIES OR SOLAR
BATTERIES?

DEEP CYCLE (SOLAR
BATTERIES)
• A deep cycle battery is designed to provide a steady amount of
current over a long period of time. A deep cycle battery can
provide a surge when needed, but nothing like the surge a car
battery can. A deep cycle battery is also designed to be deeply
discharged over and over again (something that would ruin a
car battery very quickly). To accomplish this, a deep cycle
battery uses thicker plates.

LEAD ACID (CAR
BATTEIRES)
• A car's battery is designed to provide a very large amount of
current for a short period of time. This surge of current is
needed to turn the engine over during starting. Once the
engine starts, the alternator provides all the power that the car
needs, so a car battery may go through its entire life without
ever being drained more than 20 percent of its total capacity.
Used in this way, a car battery can last a number of years. To
achieve a large amount of current, a car battery uses thin plates
in order to increase its surface area.

COMPONENTS OF A PV
SOLAR SYSTEM: CHARGE
CONTROLLER
• A charge controller, charge regulator or battery regulator limits
the rate at which electric current is added to or drawn from
electric batteries. It prevents overcharging and may protect
against overvoltage, which can reduce battery performance or
lifespan, and may pose a safety risk.

COMMON FEATURES OF A
CHARGE CONTROLLER
Maximum Power Point Tracking (MPPT): Adjusts the power
from the solar array to deliver maximum solar energy to the
battery.
• Converts excess voltage to Amperage
 Shunting: This diverts excess electricity to an auxiliary or shunt load ehen
batteries are full. eg dc fan, lights and other dc loads.

COMPONENTS OF A PV SOLAR
SYSTEM: INVERTER
• Power produced by the PV array is direct current, or DC power.
That power needs to be converted to alternating current, or AC
power, before it can be connected to the utility grid or
delivered to the AC Load. The inverter is the heart of the
system and is responsible for performing this conversion safely
and efficiently.

TYPES OF
INVERTERS
• Off Grid Inverters
• Grid-Tied Inverters

TYPES OF SOLAR SYSTEM
• Grid Tie System
• Off Grid System
• Hybrid System

TYPES OF SOLAR
SYSTEM –
GRID TIED
•Grid-tied systems are the most common
type of solar PV system. Grid-tied systems
are connected to the electrical grid, and
allow residents of a building to use solar
energy as well as electricity from the grid.

ADVANTAGES OF THE GRID-TIED
SYSTEM
• Less expense due to no use of battery
• Little maintenance Required
• Save Money due to Net Metering

COMPONENTS OF A GRID TIED SYSTEM
• PV panels (multiple panels make up an array)
• Inverter(s)

DISADVANTAGES OF THE GRID-TIED
SYSTEM
• Will not produce if there is no power from Grid

TYPES OF SOLAR SYSTEMS: OFF-GRID
• An off-grid Solar system produces power independent of the
grid. That is it is not connected to the grid.
• The system supplies power both day and night from a battery
bank which is charged from the solar panels,

COMPONENTS OF AN OFF-GRID
SYSTEM
• PV panels
• battery bank
• charge controller (to protect the battery bank from overcharge)
• inverter

DISADVANTAGES OF THE OFF-GRID SYSTEM
• More Costly to install
• Requires more maintenance

TYPES OF SOLAR SYSTEMS -
HYBRID
• Hybrid solar systems is a combination of grid-tied and off-grid
solar systems. These systems can either be described as off-
grid solar with utility backup power, or grid-tied solar with
extra battery storage.
• Some hybrid systems also have a back up generator tied in with
the system.

COMPONENTS OF A HYBRID SYSTEM
• PV panels
• battery bank
• charge controller (to protect the battery bank from overcharge)
• Inverter
• required electrical safety gear (i.e. fuses, breakers, disconnects)
• monitoring system to monitor energy production (optional)

ADVANTAGES OF HYBRID SYSTEMS
• Less expensive than off-gird solar systems i.e. without the
generator.

DESIGNING THE SYSTEM
• Systems are designed for worst month conditions such as December where
there may be less sunlight.. Also designed for worst load scenario such as a
power spike from equipment.
• The best way to go about designing your system is to first make your home
energy efficient, i.e replacing fluorescent, incandescent and other bulbs to
led bulbs, changing ac units to inverter Acs, buying energy efficient TVs and
refrigerators etc…
• Load requirements
• Location
• Roof suitability – structure, spacing, and positioning

LOAD REQUIREMENTS
• Finding the power consumption of your home or business
determines the size of your system.
• Your load requirements is determined by doing an energy audit
which gives the total energy consumption of your home or
business.
• Example.

PV LOCATION
• The Location of solar panels is crucial in determining it’s
reliability to aduately receive sunlight to power your system
and charge it efficiently.
• The solar array must be installed in an area free of shading in
order for the panels to efficiently produce.
• The panels must be installed facing south… True south vs
magnetic south
• Panel should be tilted at a angle equal to the latitude of your
location. Jamaica is 18degrees latitude so panels are tilted at an
18degree angle

PV MOUNTING
• Panels are tilted to get maximum sunlight and for self cleaning
effects
• Racking

ROOF SUITABILITY – STRUCTURE, SPACING,
AND POSITIONING
• If panels are to be installed on the roof. The roofing structure
must be stable and of suitable materials.
• Types of roofing materials is also crucial.

SAFETY!!!
• Grounding of PV System
• Disconnects
• Overloads
• PPE: Gloves, Hard Boot, Harness and Rope.
• Double checking connections
• Danger of DC Voltage

PV WIRING

BATTERY WIRING

WIRE THE SYSTEM
Conductor:
Copper and Luminium
Copper has greater conductivity than aluminuim
Copper is used
Stranded vs Solid
Stranded is highly flexible, used where larger wire size is
required.
Solid conductor is not very flexible and hard to use especially
in larger sizes.

Insulation
Provides conductor protection from heat, abrasion, moisture
UV lights, and chemicals.
WIRE THE SYSTEM

GLOSSARY
• Ambient Temperature – Temperature of surrounding Air
• PV – Photovoltaic
• DC – Direct Current – current flows in one direction
• AC – Alternating Current – Current flows in both directions
• Kilo Watt-
• Kilo Watt Hour –
• MPPT –
• Peak Sun Hours –
• Solar Irradiance – A measure of how much solar power you are getting at a location. Varies depending
on the season of year.

PRACTICA
L