PV Excite Design & Install 2 Day solar PV Excite Course An - - PDF document

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PV Excite Design & Install 2 Day solar PV Excite Course An - - PDF document

7/17/20 PV Excite Design & Install 2 Day solar PV Excite Course An entry level course for aspirant Designers and Installers that are new to PV systems PQRS Presented by Carel Ballack +27 82 322 2601 carel.ballack@pqrs.co.za


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7/17/20 1

PV Excite – Design & Install

2 Day solar PV Excite Course An entry level course for aspirant Designers and Installers that are new to PV systems PQRS Presented by Carel Ballack +27 82 322 2601 carel.ballack@pqrs.co.za

  • Presenter: Carel Ballack

– Electrician – Plumbing and gas. – Former Ombudsman for SESSA – Tenders, Project management, Electrical infrastructure, Repairs and maintenance. – Consultant – Training & development for energy sector

2

IntroducXon - Presenter

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7/17/20 2

  • Rubicon / Ellies / ACDC / Herholdts
  • Allelec / Voltex
  • Yingli / Jinko
  • TIA - Test Instruments Africa
  • ABB
  • PLP
  • Dixon
  • Schneider
  • Enel
  • Greensun
  • Mustek
  • Tesla

3

PQRS - Network

  • Green Cape
  • Western Cape Government
  • Mangosuthu University of Tech.
  • Copper Development AssociaXon
  • SAAEA
  • AssociaXon for Renewable Energy

PracXXoners

  • Earthing and Lightning ProtecXon

AssociaXon

  • Sustainable Energy Africa

OrganisaXons InsXtuXons and associaXons

  • Course rules

– Pin presenter to the screen (Microsoe teams) – Please use the chat box for raising quesXons – Please switch off video to preserve bandwidth

  • Have you downloaded any material of interest?

– Generic datasheets (Always the same) – This presentaXon in pdf

  • Tea at more or less 10:30 & 15:00

– 15 minutes each

  • Lunch at around 12:00 - 12:30

– 30 minutes

4

General Welcome

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  • Day 1

– Overview of electricity & some principles – Tools, equipment and electrical components – Understanding the funcXon of the different products

  • Day 2

– Understanding how the products work together – Aeernoon: Small system calculaXon

Programme System sizing when storage is included

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Course process and content

  • Solar PV Service Technician

– 1 year qualificaXon – N5 – Entry requirements - NQF Level 4 qualificaXon with mathemaXcs. – Consists of ±344 credits or 3440 noXonal hours – RPL – Keep record of training and installaXons

What about the formal qualificaXon?

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  • A Solar Photovoltaic Service (PV) Technician

– Performs maintenance (preventaXve, scheduled, unscheduled)

  • n PV systems in compliance with the Department of Energy

and related regulaXons, – Isolates the PV system; – Performs fault finding (trouble-shooXng), – IdenXfies deficiencies; – InformaXon Analyses, – Carries out

  • maintenance,
  • repairs (including removing and replacing components),

and

  • finds soluXons to a range of problems.

Solar PV Service Technician Informal Quality Assurance – Feel Good CerXficaXon

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7/17/20 6

  • PV Green Card vs P4
  • P4 is linked to AREP (AssociaXon for Renewable Energy

PracXXoners)

  • PV Green Card is linked to SAPVIA

Feel good plaoorms

  • Electricity is dangerous.
  • The purpose of this training course is to promote the use of

solar, for both electrical & plumbing solar technologies.

  • The instructors cannot be held liable for informaXon

presented; or the way in which informaXon has been interpreted through this; or any other training, markeXng or media plaoorm. Please read product instrucXons and comply to manufacturer recommendaXons

  • Your feedback is important
  • Please complete the feedback form.
  • We trust that you will enjoy the course

12

Content Disclaimer & Feedback

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SLIDE 7

7/17/20 7

  • Leonardo Energy - free online training for engineers (advanced)

hpp://www.leonardo-energy.org

  • Assess and determine available solar irradiaXon at a specific venue

hpps://re.jrc.ec.europa.eu/pvg_tools/en/tools.html#PVP

  • Calculate solar systems viability

hpp://www.retscreen.net

  • For free training on energy efficiency: Easy to Moderate to Advanced

hpps://www.schneideruniversiXes.com/

  • Free Book - Unlimited Energy – Describes how baperies work

hpp://www.victronenergy.com/upload/documents/Book-Energy-Unlimited-EN.pdf

  • Free Maths & Science Mastery - Training Plaoorm

hpps://www.khanacademy.org/

13

Supplementary free informaXon Tools Required for solar installaXons

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SLIDE 8

7/17/20 8

  • Special tools

– Crimper

  • Solar Crimper, PneumaXc crimper

– MulX Meter – Torque wrench – Data Logger

  • Usual Tools

– Screw drivers, pliers – Drills, grinders – Step ladders, etc

Tools required Basic electricity

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  • Benjamin Franklin

– Glass & Silk Experiment – Kite experiment

  • Electrons

– Charged ‘negaXve’ – Move from areas of abundance to areas of depleXon

  • The same principles can be seen in solar modules

17

Electron Flow

  • What is Volt?

– Voltage can be explained as being electrical pressure

  • What is Amp?

– The movement of current is measured in Amps

  • Nominal voltage
  • What is Series? See next slide
  • What is Parallel? See next slide

Basic Terminology

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  • Ohm's Law is a formula or range of formulas used to

calculate the relaXonship between voltage, current and resistance in an electrical circuit.

Ohm’s Law

  • Voltage increases and the current stays the same

Series configuraXon

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  • Current increases and the voltage stays the same

Parallel configuraXon

  • When connecXng in series the voltage is mulXplied by the number of panels to get to the

system voltage.

  • The inverter or charge controller needs to be able to operate in the system voltage temp ranges

22

Series ConfiguraXon

Modules in Series Voc Ave. Per cell Module Voc

  • 15℃

80℃ 36 Cell X 8 Modules 0,6 21,6 193 144 54 Cell X 8 Modules 0,6 32,4 290 216 60 Cell X 8 Modules 0,6 36 322 240 72 Cell X 8 Modules 0,6 43,2 387 288

Values are es-mated and have been calculated using a temp co-eff. of 0,30%/℃

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  • Using Branch

connectors

  • Same power being

produced as previous slide

  • Lower Voltage
  • Current X 2 of

a single string

23

Parallel ConfiguraXon

Modules in Series Voc Ave. Per cell Module Voc

  • 15℃

80℃ 36 Cell X 4 Modules 0,6 21,6 96 72 54 Cell X 4 Modules 0,6 32,4 145 108 60 Cell X 4 Modules 0,6 36 161 120 72 Cell X 4 Modules 0,6 43,2 193 144

24

Parallel ConfiguraXon

  • Using a combiner box
  • Same power being produced

as previous slide

  • Offers the advantage of
  • individual string

disconnecXon

  • Housing for SPD’s

To Inverter

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  • The power Triangle is a range of formulas clarifying the

difference between Power, Current and Voltage

Power triangle Solar & Electrical equipment

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  • In this secXon
  • Electrical Equipment

– Cables – Circuit breakers – Switches & DC Disconnects

  • Solar Equipment

– Modules – Baperies – Charge controllers – Loads – Inverters

Solar Equipment

  • A conductor is defined as “an object or type of material

that allows the flow of electrical current in one or more

  • direcXons. Different types of metals are commonly used

as electrical conductors.”

Conductors – (Switch to Keynote)

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Copper, aluminium and steel as Conductors

Copper Aluminium Copper coated steel

Gold as a conductor

Gold plated copper conductors

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Silver as a conductor

In the screen printing of solar cells, silver is mostly used as the conductor of choice

Tin as a conductor

Tinned copper conductors Looks silver

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  • Bare Copper Earth Wire
  • BCEW is usually used for

earthing and bonding

How copper is used How copper is used

  • GP cable is used to describe general purpose

conductors, hence the GP denotes “general purpose”. . . . . .this type of conductor is also called house wire and used in most electrical installaXons for the wiring of buildings and homes.

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  • Twin and earth
  • Twin and earth is also regularly used in buildings and

takes preference over GP wire as the live, neutral and earth wires are grouped together in one insulator

How copper is used

  • Surfix or Norsk
  • Suffix or norsk cable is usually used where electricians

don't want to use conduit as it already has an addiXonal aluminium shield underneath the insulaXon.

How copper is used

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  • Armoured cable
  • Armoured cable is normally used in slightly more

commercial or industrial applicaXons and usually buried under ground or strapped onto cable trays or wire ways.

How copper is used

  • InternaXonal Annealed Copper Standard (IACS)

Metal / Material Conductance IACS Silver 105% Copper 100% Gold 70% Aluminium 61% Brass 28% Zinc 27% Nickel 22% Iron 17% Iron 17% Tin 15% Phosphor Bronze 15% Lead 7% Nickel Aluminium Bronze 7% Steel 3 to 15%

38

Conductor resistance

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  • Where do CB fit?

– DB Boards or other suitable enclosures

  • Circuit breakers vs isolators
  • Show CB video

Circuit breakers

  • System components.
  • Solar Module
  • Bapery
  • Charge controller
  • Load
  • Inverter

Components (– Switch to Keynote)

Battery Load Inverter Solar Modules Charge Controller

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

40

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Components

Battery Load Inverter Solar Modules Charge Controller

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

  • System components.
  • Solar Module
  • Bapery
  • Charge controller
  • Load
  • Inverter

41

  • PV is short for

‘PhotoVoltaic’

  • The generaXon of

electricity in a material exposed to light

  • Modules

– Different sizes – Generate DC or Direct Current

Components - Solar PV Modules or Panels

42

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  • The front and rear

faces of solar modules are different.

Components - Solar PV Modules or Panels

Front or Face White back sheet JuncXon box

43

  • There is a posiXve

and negaXve cable connected to the juncXon box

  • Each cable has a

coupler

  • Couplers would

either be posiXve or negaXve

  • Inside most juncXon

boxes, there are bypass diodes

Components – Solar PV Modules or Panels

Diodes

44

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Components

Battery Load Inverter Solar Modules Charge Controller

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

  • System components.
  • Solar Module
  • Bapery
  • Charge controller
  • Load
  • Inverter

45

  • 12V Lead-Acid Baperies

– Store electricity in DC or Direct Current and are energy storage devices – Each cap represents 1 cell – Consists of 6 cells – Have posiXve and negaXve terminals – Lead-Acid baperies are sold in Amp-hour capacity, usually denoted with an “Ah” on the side of the bapery

Components - 12 Volt Lead-Acid Baperies

This is a cell 6 cells in a 12V bapery

46

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  • The bapery will charge when

connecXng the – posiXve cable from the panel to the posiXve terminal of the bapery – NegaXve cable from the panel to the negaXve terminal of the bapery

  • This way of connec-ng is

dangerous because the baMery could over-charge

Charging

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

47

Components

Battery Load Inverter Solar Modules Charge Controller

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

  • System components.
  • Solar Module
  • Bapery
  • Charge controller
  • Load
  • Inverter

48

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  • Charge controllers or

regulators protect baperies from

  • vercharging
  • There are different types

and sizes of charge controllers i.e. MPPT or PWM, 20A, 40A, 60A, 12V, 48V and many more. Some make provision for loads and some don’t.

Components – Charge Controllers

PWM

24V MPPT Charge Controller Charge Controller 12/24V 49

  • Provided that the

products are suited to

  • ne another, the

bapery can be charged safely as the charge controller may prevent the bapery from being

  • vercharged.
  • See charge controller

se|ngs for correct configuraXon

Components – Charge Controllers

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

50

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Components

Battery Load Inverter Solar Modules Charge Controller

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

  • System components.
  • Solar Module
  • Bapery
  • Charge controller
  • Load
  • Inverter

51

  • How do we connect

loads?

  • Loads are components

that consume electrical power.

  • Examples of electrical

loads are lights, TV’s, Laptops, other appliances, etc.

  • There are AC and DC

loads

Components - Loads

52

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Components

Battery Load Inverter Solar Modules Charge Controller

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

  • System components.
  • Solar Module
  • Bapery
  • Charge controller
  • Load
  • Inverter

53

  • Inverters invert DC to

AC

  • Although this type of

connecXon can work. It’s not safe. As AC Circuits need some form of protec-on the circuit could also do with some switches, fuses and circuit breakers.

Components - Inverter

+

  • Battery

12 Volt 230 Volt Load

DC Supply AC Load

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

54

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7/17/20 28

  • Solar Modules generate DC
  • Baperies store DC
  • Solar modules can be used to charge

baperies

  • Charge controllers protect baperies from

being overcharged through configuraXon

  • Inverters use DC to power AC electrical loads
  • Electrical loads will cause baperies to

discharge

  • Some Inverters can be adjusted to prevent

baperies from discharging completely.

  • Take care, read instrucXons and understand

data sheets when considering equipment for a specific solar system.

Component - Summary

Battery Load Inverter Solar Modules Charge Controller

55

Solar Equipment working together

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7/17/20 29

  • Provided that the

products are suited to

  • ne another, the

bapery can be charged safely as the charge controller may prevent the bapery from being

  • vercharged.
  • See charge controller

se|ngs . . . .coming up

Components – Charge Controllers (– Keynote)

  • How do we connect

loads?

  • Loads are components

that consumes electrical power.

  • Examples of electrical

loads are lights, TV’s, Laptops, other appliances, etc.

  • There are AC and DC

loads

Components - Loads

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  • Inverters invert DC to

AC

  • Although this type of

connecXon can work. It’s not safe. AC Circuits need some form of protec-on. The circuit could also do with some switches, fuses and circuit breakers. Coming up . . . . .

Components - Inverter

  • This is known as an Off-Grid system
  • Can operate independently without other power sources

Off-Grid systems

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  • Solar Panels do not work at night or when it is
  • vercast or raining
  • Baperies can be charged with an AC Charger when

using an alternaXve AC power source

Components – AC Charger

  • Hybrid systems can charge a set of baperies from more

than one source.

  • Some hybrid systems are connected to the grid and some

aren’t.

Hybrid systems

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  • Add control and configuraXon capability to system on

previous slide

Voltronic - Axpert

  • Typical or tradiXonal UPS’s do not have solar capability

UPS – Uninterrupted Power Supply

slide-33
SLIDE 33

7/17/20 33

  • Solar capability can be added as an external source

UPS with solar

Solar Panel / Module

  • Solar Modules generate DC
  • Baperies store DC
  • Solar modules can be used to charge baperies
  • Charge controllers protect baperies from being
  • vercharged through configuraXon
  • Inverters power electrical loads
  • Electrical loads will cause baperies to discharge
  • Some Inverters can be adjusted to prevent baperies from

discharging completely.

Component - Summary

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Different types of systems

  • Off-Grid systems
  • Systems operaXng independently from other sources
  • Hybrid systems
  • MulXple sources
  • UPS systems
  • AC Charged

Bapery Backup Systems

68

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  • Inverters invert DC to

AC

  • Although this type of

connecXon can work. It’s not safe. As AC Circuits need some form of protec-on the circuit could also do with some switches, fuses and circuit breakers.

Components - Inverter

+

  • Battery

12 Volt 230 Volt Load

DC Supply AC Load

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

69

  • Provided that the

products are suited to

  • ne another, the

bapery can be charged safely as the charge controller may prevent the bapery from being

  • vercharged.
  • See charge controller

se|ngs for correct configuraXon

Components – Charge Controllers

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

70

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Components – Charge Controllers & inverters

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

+

  • Battery

12 Volt 230 Volt Load

71

  • This is known as an Off-Grid system
  • Can operate independently without other power sources

Off-Grid systems

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

72

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  • Solar Panels do not work at night or when it is overcast or

raining

  • Baperies can be charged with an AC Charger when using an

alternaXve AC power source

Components – AC Charger

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

73

  • Hybrid systems can charge a set of baperies from more

than one source.

  • Some hybrid systems are connected to the grid and some

aren’t.

Hybrid systems

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

74

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  • Although it says

“Inverter” on the box, there is a lot more going on inside the box

  • Let’s take a quick

look at how this unit can be explained in more detail.

Voltronic - Axpert

Cables are terminated in this secXon Changes and se|ngs are made here 75

Voltronic - Axpert

+

  • Battery Bank

12 Volt

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations cables should be sized according to standards and based on site conditions and application

+

  • Solar Array

230 Volt Load

76

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  • Add control and configuraXon capability to system on previous slide

Voltronic - Axpert

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

77

  • Typical or tradiXonal UPS’s do not have solar capability

UPS – Uninterrupted Power Supply

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

78

slide-40
SLIDE 40

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  • Solar capability can be added as an external source

UPS with solar

Solar Panel / Module

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations

79

  • UPS systems provide customers with power security during

load-shedding and power outages

  • UPS systems historically did not make provision for solar
  • With hybrid systems mulXple sources can be uXlized to charge

a set of baperies.

  • Any type of device connected to a bapery needs to be

configured properly in order to ensure opXmum performance and to prevent damage to the bapery bank

  • Hybrid inverters have components inside of them that expand

their capability beyond that, of the tradiXonal inverter.

Component - Summary

80

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Line Diagrams

  • Important

to remember system considera Xons during the design stage.

SchemaXc diagrams

According to SA regulaXons, every system should have a C.o.C issued with it to ensure safety.

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  • GeneraXon, transmission and distribuXon lines all form

part of the uXlity network or Grid

What is a Grid TradiXonal ConnecXon Normal Eskom InstallaXon

slide-43
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“Grid-Tied” Solar system

Small Scale Embedded Generator

Off-Grid Solar System No connecXon to Eskom Grid

slide-44
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Hybrid System CombinaXon of both

Huge Grey Area

IrradiaXon

slide-45
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7/17/20 45

Reference: Duffie Beckman 1991

89

The solar constant – World RadiaXon Centre ReflecXon, DeflecXon & AbsorpXon

90

Irradiance

1000w/m2

IrradiaXon

400 - 700w/m2

Solar Thermal

130 - 180w/m2

Solar PV

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7/17/20 46

91

  • Peak Sun Hours are

used to calculate power generaXon of PV modules

  • Peak Sun Hours can

be calculated by dividing annual sun hours by the number

  • f days per year.
  • e.g. 2000kWhrs/m2

divided by 365 = 5,47kWh/m2

Sun hours calculaXon

E N W

92

Summary - Impact of orientaXon

  • 1000W/m2 is used

as the reference value and global average.

  • Solar IrradiaXon

varies according to region and season.

slide-47
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7/17/20 47

System CalculaXon

  • D.O.D

– Depth Of Discharge

D.o.D & RTE

  • R.T.E

– Round Trip Efficiency

slide-48
SLIDE 48

7/17/20 48

95

Lead Acid Charging cycle - 3 stages

Bulk AbsorbXon Float Time Voltage

Voltage Current

Bulk charge (aka constant current charge) Current stays constant and voltage increases Absorbtion Charge (aka Topping charge) Voltage remains constant and current drops consistently until battery is fully charged Float stage Charge voltage is reduced to between 13 & 13,8V and held constant while the current is reduced to less than 1% of battery capacity.

96

Depth of Discharge vs Cycles

slide-49
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7/17/20 49

System sizing when storage is included Inverter datasheet – as reference

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99

Step 1 - Calculate consumpXon

Step 1.b) Daily ConsumpXon in Wh Step 1.a) Power Requirement in W

  • Lead Acid System Losses vary between

±22 to 30%

100

Step 2 - Bapery Sizing

Inverters 5 5 2 15

Inverter Charge controller Cabling System (Batteries + connections)

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7/17/20 51

Step 2.a) Multiply daily consumption with losses (as a factor) = 770Wh x 1,27 = 978Wh Daily Storage required Step 2.b) Divide Daily storage by DC voltage = 978Wh / 24V = 41Ah of Average Daily Ah needed Step 2.c) Adjust to depth of discharge = 41Ah / 0,5 = 82Ah Sub Total of storage required

101

Bapery Sizing – Lead Acid

This value represents 27% Losses The “48V” value is found in the datasheet Step 1.a showed us we need 125W of Power. At least an 300W to 500W inverter would be required. For this calc. it is assumed the customer would want to increase his system over Xme. From the datasheet, we will see the 3000W inverter uses a 24V bapery / bapery bank. Use 0,5 for 50% D.o.D, 0,4 for 40% D.o.D and so on . . . . .

Step 2.d) Make provision for rainy days =82Ah x 2 days = 164Ah Total Storage required The battery bank needs to be 24V 164Ah according to our calculations. Step 2.e) Select battery to match both both 24V and 164Ah as close as possible.

102

Bapery Sizing – Lead Acid

This value is just a guess and would vary based on the number of rainy days for that area

12 Volt Bapery 200Ah 2 baperies in series to reach 24V 200Ah

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7/17/20 52

Bapery Sizing – Lead Acid

  • Step 2.f) Check to ensure that the chosen bapery can handle

the rate of discharge (c-raXng)

= 200Ah @ C20 = 200Ah at a Capacity of 20hrs = 200Ah / 20hrs = 10A

The chosen bapery can handle a rate of 10A for a period of 20 hours and then it will be completely discharged. We do not want to discharge the bapery completely and ideally should size according to less than half of the number of hours where the D.o.D is intended to be 50%

Power = Voltage x Current = 24V x 10A = 240W

240W is what the bapery bank can handle in POWER discharge rate 104

Discharge rate

From Step 2f. – The bapery bank can handle 240W. At max we will only discharge at 125W

slide-53
SLIDE 53

7/17/20 53

105

Conductor current carrying calculaXon

3000W Inverter

I = __ P V

TV 200Ah 24 Volt Battery Bank

Steps conXnued

Step 3.a) Calculate Power required to charge batteries Power = Volts x Amps

  • Where:

Volts = The battery’s absorption voltage Amps = Maximum Current the battery bank can handle

This information will be found in your inverter datasheet or charge controller datasheet or charge controller rating – Depending on what is being used to charge the batteries. The rate of charge from the charge controller and AC charger has to be balanced with rate at which the battery can accept charge. See the next slide. . . . .

slide-54
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7/17/20 54

Bapery bank charge rate

  • Bapery bank charge rate
  • = 20% of C20
  • = 20% of the Capacity of the bapery at 20hrs
  • = 20% of 200Ah
  • = 40A

200Ah 24 Volt Battery Bank

The battery can handle a maximum charge rate of 20% at C20.

This is our maximum charge rate as well as the current value required for our calculaXon

Choose method of charge

  • AC Charger
  • Charge controller
  • Other means of charging
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Bapery bank charge Voltage

  • Power (Waps)

= V (Volts) x I (Amps)

  • = 28,8 V x

20Amps

The voltage value also comes from the datasheet.

  • Power (Watts) = Volts

x I (Amps)

  • = 28,8 V

x 20 Amps

  • = 576 Waps

This 576 Watt value is the absolute maximum power required for the battery bank.

Module/Panel SelecXon

  • Step 3.b) Select modules to match

– Power Requirement, – Roof space – Ease of handling – And stock availability

From page B2 the 60 Cell 260W module is selected

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  • ObjecXve: Calculate the module’s summer and winter voltages
  • Summer Voltage is the lowest possible voltage at the highest

temperature

  • Winter Voltage is the highest possible voltage at the lowest

temperature

Temp co-efficient calculaXons

Winter Summer Module Voltages are High Temperatures are low Module Voltages are Low Temperatures are high

Module Temp coefficient calc

  • We need to know what the minimum and maximum voltages for the

module is going to be. For this step we use factors from the SANS 10142-1-2 standard.

  • Summer voltage factor of 0,75
  • Winter voltage factor of 1,15
  • Summer Min Voltage
  • 30,9 V

x 0,75

  • 23 Vmp Min
  • Winter Max Voltage
  • 30,9 V x 1,15
  • = 36 Vmp Max
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  • -0,45%/℃ 260W 60 cell
  • Eff of temp = 30,9Vmp x 0,45%/℃
  • = 0,139V

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Temperature co-efficient calcs

23Vmp 80℃ 25℃

  • 15℃

STC MulXply co-efficient factor 30,9Vmp 36Vmp Maximum Voltage (VDC-max) = Vmp Max_STC (Solar PV) x 1.15 =Vmp Min_STC*0.75 MulXply co-efficient factor

Select the charge controller

+

  • Battery Bank

24 Volt

Images are used for explanation purposes only - Circuit breakers, switchgear and safety devices should be included in all installations cables should be sized according to standards and based on site conditions and application

+

  • Solar Array

230 Volt Load

114

24V 24V

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Steps conXnued

Step 4.a) Module layout and design is done according to charge controller power, voltage and current

  • limitations. (Group Exercise)

THE END THANK YOU!!

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