Solar: All About

By Aluschka V Heerden

It is the first volume about solar. Easy to follow study guide with discussions, examples and explanations on how solar works. The first section deals with how solar panels work, and how to do design systems based on individual requirements. The book explains how to establish the correct size charge controller, and its uses. Then batteries are discussed; how to do battery designs based on requirements. In terms of inverters, explanations and discussions of how inverters work, and how to determine the size of the inverter for your specific requirements is also a critical aspect within solar.
There are also discussions on battery chargers. Extensive information on this section is also covered.There are energy saving tips and information on solar refrigeration, freezers, solar pumps and solar geysers. The whole book is easy to follow sequence with applied everyday examples to improve understanding, bringing theory and practise closer together.Also underlying aspects of climate change is highlighted and how to combat it.I hope everyone that reads this book will enjoy it. Enter the world of knowledge thoroughly.

• Language: English
• Publisher: Xlibris UK
• Release date: Nov 9, 2011
• ISBN: 9781477174395

Book preview

Copyright © 2011 by Aluschka V. Heerden. 302707-HEER

Library of Congress Control Number: 2011916198

ISBN: Softcover 978-1-4653-5433-4

Hardcover 978-1-4653-5434-1

ebook 978-1-4771-7439-5

All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without permission in writing from the copyright owner.

Xlibris Corporation

0-800-644-6988

www.xlibrispublishing.co.uk

Contents

Introduction

HOW SOLAR PANEL WORKS

Section 1

SOLAR REGULATORS / MPPTCHARGE CONTROLLERS

Section 2

SOLAR BATTERIES

Section 3

INVERTERS/CONVERTERS/UPS

Section 4

GENERAL

CONCLUSION

REFERENCES

Introduction

This book consists of a broad theoretical and practical framework and explanations with different easy-to-follow examples, consisting of four basic sections – solar design, installations, use, and general information. You will note a simple sequence of explanations throughout the book: solar panels, MPPT (maximum power point tracking) charge controllers or regulators, solar batteries, and inverters. I will explain and give examples (abbreviated as ‘i.e.’) on what solar power is and how it works, throughout this book. Things that I have underlined are important to know and to understand.

(When I refer to framework, I mean our own knowledge and insight can be useful, throughout the book).

I will end with a recap summary, emphasising that when using solar panels, one must know how many wattages (in terms of appliances) will be used for approximately how long. One of the aims of this book is to give everybody that reads this book a better understanding on solar energy and an awareness of the importance green energy plays for the future of humankind. Throughout this book I will also state my personal opinions and viewpoints. It may sometimes be debated, and as I have stated throughout, it does not have to be correct. Solar as a ‘system’ or flow – I will discuss each component or section, which will be understood at the end of the book!

(In some parts of the book you will notice a lot of information at once, but it will fit in together at the end of each section; this is why I say, all the sections are related to each other, not independent by themselves. Read the whole book.)

It is very important to note that the whole book is related to each other. It must not be studied as separate components, but rather as one entity. Recapping the whole book a few times is recommended after reading the first time. Understanding may first happen at the end of the book after several readings, depending from individual to individual.

Please note that throughout this book the following abbreviations are used: i.e. – for example

DC – direct current (normally, i.e. 12/24/36/48 volts…)

AC – alternating current (normally, i.e. in SA 220 volts…)

MPPT – maximum power point tracker

DB – distribution board etc – etcetera, and so on.

In this specific book, I write about Escom 220 volts municipal electricity (the grid, alternating current. This is in the SA context. Other countries might differ in voltage, i.e. 210/220/230/240 volts…); it is also referred to as ‘grid’.

Please also note the following (this is fundamental and is very, very important):

V is referred to as volt.

A is referred to amp/ampere.

W is referred to watt/wattage.

Some things are repeated for easier understanding. As we all become aware, going green is a current affair in saving our planet. Please enjoy the reading!

I would recommend, when buying solar panels, buying a wattage monitor so that wattage used can be seen. Do not try to spare money. I believe if someone does something, it should be done properly and correctly from the beginning.

HOW SOLAR PANEL WORKS

Section 1

Picture of a Solar Panel

(There are different types, sizes, brands . . . on the market, discussed later and throughout the book)

image004.tif

Solar panel works from the light of the sun, ‘converting’ sun into electricity (even if it’s a bit cloudy)

Welcome to alternative power generation solar power (DC, direct current), from the sun. This should be used wisely (because less sun, less usage); I hope you will enjoy the book.

To design a system know what is going to be used, and for how long,

How? It will be discussed later.

Illustration of how solar power from the Sun works (referring to a complete system)

In solar panels connection goes towards the charge controller (could be MPPT regulator (by means of electric wire) (MPPT regulator, depending on system type etc), then towards batteries (also by means of electric wire), and then with battery cables extending towards inverter. 220-volt (input) appliances can then be plugged into the inverter, or the inverter connected into DB. (Please note, as will be understood after the whole book is read: in backup systems, panels are not necessary; if generator, with battery charger; (inverter charger) or municipality electricity is installed (in these cases, ‘backup systems’ refers to energy when municipal energy goes off or generator is turned off.)

(You will notice this whole book follows this order as far as possible)!

image006.tif

(These images from: www.googleimages.co.za)

With all the above diagrams in mind:

How do you know how many solar panels you need in your solar (battery) energy, electricity system?

(a)

In order to establish how many solar panels you need, you would have to first work out how many watts (in terms of appliances) you plan to use (the exact wattage) and for how long (the exact duration) you want to use these specific appliances for, and then you calculate X (times) the wattages you calculated, with how long the appliances will be used for.

This is critical in designing a system based on usage from the sun.

In general, solar panels normally get between six to eight hours of sunlight each day (in SA), in the summer. This also depends on (i.e. cloudy days, losses) or what quality solar panels you have and other factors also. Let us take an example: Say, for instance, you plan to use 4,000 watts (5.2 kva/4 Kilowatt; kw; to be mechanical) a day (normal household without geyser and stove), and you prefer 180 watts (every hour) solar panels, then you would need four panels, because 180 watt x 4 panels × six hours of potential sunlight a day will give a number of 4,320 watts, that fits into your requirements.

(b)

When you have cloudy days of four to five days, and your inverter does not have a built-in charger, you can charge your batteries with a battery charger (12v/24/36… depending on how your battery system is connected). In this case, it is important to understand that you need more batteries for those cloudy days (Don’t worry. This principle will be discussed later.)

When you do not have, in SA terms, Eskom (220 volts) electricity, you can use a generator. (Please also remember not to use your batteries until it’s empty, because you can injure or damage the batteries.)

Further explanations will be discussed under ‘MPPT charge controllers’, solar batteries, battery chargers, and inverters or converters, just to give you a full idea of solar electricity, after you have read each section.

(This information mentioned as explained above is only a broad technical outline (broad guidelines) of the basics of solar electricity.)

(c)

In order to establish how many watts an appliance consumes volt X (Times) amp = watt. (volt and amp will normally be written on the appliances).

(Volt in South Africa is normally 220 volts. From this information, calculations are easy!)

(These amounts or numbers are worked out in terms of how much it uses in an hour; so remember, if you want to use computer that uses 120 watts an hour, you must X (times) it with how long you want to use it for (as explained above). It is important to note that calculating a refrigerator for use the whole day, calculate the wattage it consumes in an hour (discussed later) and X (times) it with 14 (only applied to certain refrigerators), to establish how many energy must come in from solar panels to power the batteries, in order for your refrigerator to work for the whole day: 14 because that’s normally how many times fridges switches on and off during the day!

Also remember, some appliances you will use and switch of again, so those appliances doesn’t take much, but still calculate them on an hourly basis, that’s better, in my opinion, there are many different opinions on this specific topic.

The next table are only an indication on how many wattage certain appliances can use, good know of this also when trying to establish how many wattage you plan to use, and to establish how many solar panels you would need.

Solar panels normally give out power every hour the sun shines, i.e. 210 watt every hour, in SA normally six hours of sunshine in a day.

Very important calculations to know within solar and electricity/electronicsin general:

Volt (V) X (times) amp (A) = watt (W). (Very important when we come to calculating watts in batteries and inverter sizes… These will be discussed later). watt (W) divided by volt (V) = amp (A)

Volt in South Africa is always 220. This is how plugs are made to work on Escom electricity (i.e. in the plug three wires live, neutral (positive brown, negative blue): if you look at the plug with long point towards you, it’s on the right, and earth (green, yellow); other countries have 210/230/240 volts… In America, positive is black wire and negative white wire, the positive dangerous, and in SA, the brown (positive) is dangerous.

(In the United States, they don’t have earth connection in their plugs, i.e. protection lightning attraction.)

Example of a South African electrical plug

image008.tif

The UK plug normally