Thursday, June 26, 2014

Setup a Samba Media Server on uBuntu

1. Prerequisites
- Your Linux box should have an static ip-address.
In case you're getting your ip from a router/server via DHCP make sure it's configured to provide a fixed dhcp-lease. If that's no valid option you cannot use WINS ... more on this way down.
- You need to have samba installed.
If you haven't done so already open a terminal and type:

Code:

sudo apt-get install samba

Don't close the terminal upon installation - we still need the commandline to get several tasks done!
2. Getting samba configured
First, let us make sure samba isn't running:

Code:

sudo /etc/init.d/samba stop


As a starting point I included an smb.conf below, and there are only a few simple things you may need to tweak.

Since the installation of samba just installed a rather useless template file we're going to rename it - we keep the file just in case.



Code:



sudo mv /etc/samba/smb.conf /etc/samba/smb.conf.template


Next we create a new empty file



Code:



sudo touch /etc/samba/smb.conf


And finally we need to open the file inside an editor



Code:



sudo gedit /etc/samba/smb.conf


NOTE: If you're on KDE replace "gedit" with "kate"


Copy / Paste the contents of the code-section below into your editor and read on ...



Code:



[global]
; General server settings
netbios name = YOUR_HOSTNAME
server string =
workgroup = YOUR_WORKGROUP
announce version = 5.0
socket options = TCP_NODELAY IPTOS_LOWDELAY SO_KEEPALIVE SO_RCVBUF=8192 SO_SNDBUF=8192

passdb backend = tdbsam
security = user
null passwords = true
username map = /etc/samba/smbusers
name resolve order = hosts wins bcast

wins support = yes

printing = CUPS
printcap name = CUPS

syslog = 1
syslog only = yes

; NOTE: If you need access to the user home directories uncomment the
; lines below and adjust the settings to your hearts content.
;[homes]
;valid users = %S
;create mode = 0600
;directory mode = 0755
;browseable = no
;read only = no
;veto files = /*.{*}/.*/mail/bin/

; NOTE: Only needed if you run samba as a primary domain controller.
; Not needed as this config doesn't cover that matter.
;[netlogon]
;path = /var/lib/samba/netlogon
;admin users = Administrator
;valid users = %U
;read only = no

; NOTE: Again - only needed if you're running a primary domain controller.
;[Profiles]
;path = /var/lib/samba/profiles
;valid users = %U
;create mode = 0600
;directory mode = 0700
;writeable = yes
;browseable = no

; NOTE: Inside this place you may build a printer driver repository for
; Windows - I'll cover this topic in another HOWTO.
[print$]
path = /var/lib/samba/printers
browseable = yes
guest ok = yes
read only = yes
write list = root
create mask = 0664
directory mask = 0775

[printers]
path = /tmp
printable = yes
guest ok = yes
browseable = no

; Uncomment if you need to share your CD-/DVD-ROM Drive
;[DVD-ROM Drive]
;path = /media/cdrom
;browseable = yes
;read only = yes
;guest ok = yes

[MyFiles]
path = /media/samba/
browseable = yes
read only = no
guest ok = no
create mask = 0644
directory mask = 0755
force user = YOUR_USERNAME
force group = YOUR_USERGROUP


Ok, I already mentioned that there are a few simple things you may need to tweak; so here they are:

-> netbios name = YOUR_HOSTNAME


Replace "YOUR_HOSTNAME" with your desired hostname (don't use spaces!). Best pratice would be to use the same name you configured upon installation.


Example:


netbios name = DAPPER


-> workgroup = YOUR_WORKGROUP


Replace "YOUR_WORKGROUP" with the name of your workgroup, but make sure you're using the same as configured in Windows.


To find out the Workgroup name in Windows follow these steps:


- Click "START"


- Click "Control Panel"


- Click "System"


- Click the 2nd Tab entitled "Computername" and find the name of the Workgroup there.


Example:


workgroup = MSHOME


-> wins support = yes


If your box doesn't have a static ip-address, or you cannot configure your router/server to provide you with a fixed dhcp-lease, change this configuration parameter to "no".


In this case you cannot use the benefits of WINS.


-> [MyFiles]


This is the name of the share. Leave it as it is or adjust it to whatever you prefer. Don't use more than 31 characters and try to avoid spaces!


-> path = /media/samba/


This suggests that you've mounted an hard drive or partition on /media/samba where all the shared files will be stored.


In case you don't have an extra hard drive/partition you may also create folder.


I assume you've been wise enough to put /home onto a separate partition having an reasonable amount of storage space.


To create the folder type (inside a new terminal) ...



Code:



sudo mkdir /home/samba


... and adjust "path =" to read ...

path = /home/samba/


Remember that this is just an example - you are free to put things wherever you like.


-> force user = YOUR_USERNAME


-> force group = YOUR_USERNAME


Well, this should say it all. Replace "YOUR_USERNAME" with the name you use for login (no spaces!).


Example:


force user = stormbringer


force group = stormbringer


Now we completed the part of editing smb.conf


Save the file and close gedit.


Since we are going to share the folder with other users we should now make sure that the permissions are set. Type:



Code:



sudo chmod 0777 /media/samba


NOTE: Don't forget to correct the path to the location you chose above!


That's it - now we need to start samba ...


1.1 Starting samba and setting up user accounts


Let us fire up samba for the first time. Type:



Code:



sudo /etc/init.d/samba start


NOTE: If the above command doesn't work for you, try:



sudo smbd reload


Once Samba has restarted, use this command to check your smb.conf for any syntax errors





testparm


Time to add yourself as an samba user.

NOTE: You will be asked for a password - make sure you use the same as you use for login!



Code:



sudo smbpasswd -L -a your_username
sudo smbpasswd -L -e your_username


In case you need other users to be able to access the share you need to add them to your system AND samba as well. Make sure you use the very same Windows usernames and passwords!

NOTE: Windows XP doesn't set passwords for its useraccount per default. If you haven't set a password on your XP box just press enter when prompted to enter a password for the user account you're about to create!


In the following example we will add an user called "mark" ...


Example:



Code:



sudo useradd -s /bin/true mark
sudo smbpasswd -L -a mark
sudo smbpasswd -L -e mark


The "-s /bin/true" in the first line prevents the users from being able to access the commandline of your linux box ("-s" stands for "shell"). I strongly advise you to follow this recommendation! Don't change that setting to a valid login-shell unless you really know what you are doing!

Repeat this step until you configured all user accounts!



 



File Sharing (Advanced)



We started with the base of Samba file-sharing. The above-mentioned items should be enough to get you started. Next we will add details that you might or might not need.



If you have more than one network card


If you have more than one network card (or interface) then you have to define where you want Samba to run. In smb.conf under the [global] section, add:



interfaces = 127.0.0.1, 192.168.0.31/24
bind interfaces only = yes


The first address (127.0.0.1), is a loopback network connection (it's your own machine). The second address (192.168.0.31), is the address of the card you want Samba to run on, the second number (24) is the subnet default for a CLASS-C network. It may vary depending on your network.



With "bind interfaces only" you limit which interfaces on a machine will serve SMB requests.



You can limit which IP address can connect to your Samba server adding these lines:



hosts allow = 127.0.0.1, 192.168.0.31, 192.168.0.32
hosts deny = 0.0.0.0/0


The loopback address must be present in the first line. The second line deny access from all IP address not in the first line.

Tuesday, June 24, 2014

Enable Chrome Remote Desktop on Linux (Ubuntu)

On linux when running Chrome Remote Desktop extension in chrome you will notice that it does not give you an option to add the computer as shown in the image below

The solution is not that well documented out there on the web, Google?
the following instructions are for Ubuntu, I have tested them successfully on Ubuntu 14.04
Edit:
sudo nano /etc/apt/sources.list.d/chromeos.list
Add the google Repository:
deb http://dl.google.com/linux/chrome-remote-desktop/deb/ stable main
Install:
sudo apt-get update
sudo apt-get install chrome-remote-desktop
sudo /etc/init.d/chrome-remote-desktop start

Then go back to Chrome Remote Desktop Extension and the following option will be available.

Tuesday, June 10, 2014

How to Build Your Own Network-Attached Storage System

With cheap storage readily available, the temptation to build vast libraries of music, movies, photos, and documents is ever present. But when each PC in your home is packed to its aluminum gills with gigabytes upon gigabytes of digital goods, managing all of that data can be a hassle.

Network-attached storage can make wrangling data much easier. Imagine a single machine on your network slinging files to every PC in your home, managing backups, and safeguarding all of your important memories or sensitive data.

Plenty of network-attached storage appliances on the market are ready and able to tackle your storage needs, but buying one can be an expensive option--particularly if you have only a few files that you want to share with a few machines. Things get even more problematic for those users who have terabytes upon terabytes of data: You can expect to pay dearly for a NAS that’s equipped to handle your digital hoard.

Fortunately, building your own NAS is simple. And doing so offers a lot of advantages over forking over your hard-earned cash--build your own, and you can dictate its size, feature set, and storage capacity, and change things on a whim.

Choosing the Software

A wide variety of operating-system options are available for setting up your own NAS. Many popular Linux distributions offer a server-oriented variant, with instructions on getting your file server up and running. But we’re going to keep things simple and go with FreeNAS.

FreeNAS is a popular choice, as it’s fairly easy to configure once all of the hardware is in place. You can download the latest version from the FreeNAS website. Burn the .iso file you download onto a CD or DVD; in Windows 7, just right-click the file and select Burn disc image. For other versions of Windows, you can use the free ImgBurn utility.

Choosing the Hardware

Now that you have a copy of FreeNAS, let’s talk hardware. FreeNAS will run on just about anything, so an old PC you’re not using anymore will work just fine. For optimal performance, you’ll want to have at least 4GB of RAM.

For my FreeNAS build, I pulled a few spare parts together. My NAS centers on a Gigabyte E350N motherboard, equipped with an AMD E-350 processor. I picked this motherboard because it's small, it draws little power, and it can fit into small spaces, yet it offers four SATA ports for my hard drives. When choosing a system (or building your own), make sure that the motherboard has room to support all of the drives you want to use for storage.

I collected three spare 1TB drives for storage, plus a spare DVD drive to handle the installation. When FreeNAS is installed, it takes over the entire drive you install it on. To keep all of the storage drives available, I also grabbed a 2GB USB key, to host the the operating system.

The Setup: Installing FreeNAS

With the hardware selected and the FreeNAS CD at the ready, it’s time to get started.

Insert the DVD and USB key into the computer you’re setting up as your NAS. Before you start the machine up, be sure that the ethernet cable is plugged into the motherboard. You’ll also want to have another computer that’s connected to your network up and running, as you’ll be using it to connect to and configure the NAS.

Start up the PC and enter the BIOS. The steps to getting into the BIOS will vary depending on your motherboard, but the general rule of thumb is to mash the F2, F7, F8, or Delete key while the PC is booting up--watch the monitor after you’ve pressed the power button, and the instructions will scroll past during the normal startup sequence.

Once you’re in the BIOS, set the machine to boot from the optical drive. The steps will once again vary based on your motherboard model, but you should see a section that lists a Boot Priority order. Once you've set that, press F10 to save and exit; the machine will restart, query your optical drive, and then start loading FreeNAS from your CD.

You’ll know that FreeNAS is running when you see a plain blue screen with a list of options. You want to install FreeNAS onto your USB key, so select the very first option. FreeNAS will list arcane drive model numbers, so looking for the capacity of the USB key (in this case, 2GB) should be the easiest approach. Follow the prompts; FreeNAS will warn you that it will delete everything off of the USB key. Click through that message, and then go get a cup of tea while the progress indicator rolls over to 100 percent complete.

Once it’s done, you’ll see a prompt to eject the CD and reboot the machine. When your computer restarts, it should boot FreeNAS from the USB key--if it doesn’t, head back into the BIOS, set the motherboard to boot to the USB key, and restart again.

As FreeNAS is starting up, it will present lots of arcane lines of code, followed by a numbered list and a Web address to connect to. This is normal. That URL is the network address of your new file server. Type that address into a browser on a computer in your home that’s connected to the same network as the NAS, and you’ll reach the FreeNAS configuration screen.

FreeNAS will prompt you for a username and password. The default user name is “admin,” and the default password is “freenas.” You can change the default to whatever you’d like in the FreeNAS options.

If you ever forget your password, resetting it is fairly easy. You need to head over to the NAS, and type the following command:

Python /usr/local/www/freenasUI/manage.py changepassword admin

FreeNAS will then prompt you to enter a new password.

The Setup: Building Volumes

Once you’re logged in, the first thing you’ll want to do is create the file system. Click Storage at the top of the menu bar, and then select Create volume. In the window that pops up, select all the drives you want to include, and give the volume a name.

You’ll have two options to choose from: UFS (Unix File System) and ZFS. We’re going with ZFS, as it offers support for numerous features designed for file servers, such as RAID support, snapshots, and file compression.

Depending on the number of drives in your machine, you’ll see a few new options. With three drives, I get a choice between mirror, stripe, and RAID-Z. Mirror duplicates data from one disc across the others, as RAID 1 would. Stripe splits files among the discs in the array, as RAID 0 would. RAID-Z is essentially a software implementation of RAID 5.

So what does all of that mean? With my three 1TB drives, selecting the mirror type gives me 1TB of total storage capacity, but preserves my data across all drives; if one drive fails, I can replace it and keep moving. Stripe gives me 3TB and a very fast response time; lose one drive, though, and all of that data is gone. RAID-Z is a sort of amalgam of the two: It gives me 2TB of space, and if one of the three drives fails, my data can be rebuilt from the remaining pair while I find a replacement.

Because I like to live on the edge, I’m going with the striped option. It isn’t the safest alternative, but I’ll squeeze out every bit of space, and I can always implement a safer, redundant backup solution later on.

Whatever you choose, be aware that any data on the discs will be wiped. Click Add volume, and moments later your file server is almost ready to go.

Sharing Your Files

You have your storage volume in place, so now you can fill it with photos of pets, as well as your legally acquired media.

FreeNAS makes it easy to share files with Linux, Apple, and Windows computers. You can create as many shared folders as you’d like--say, a Windows/Unix/Apple share for your movies and music collection, and an Apple-specific share for your Time Machine backups.

The first step is to enable the CIFS (Common Internet File System) service. ClickServices on the left, and then click the button for CIFS. Click the wrench next to the CIFS line to set your workgroup, assign other network and user permissions, or just give your NAS a readily identifiable name. You’ll be typing this name in to access your file server from Windows machines.

On the navigation bar at the left, click the tab conveniently labeled Sharing. I’ll set up a Windows share as an example here, but the instructions for Linux and Apple are fairly similar.

Click Add Windows Share, and give it a name in the window that pops up. Click the drop-down menu next to 'Path' to assign your NAS to an address that Windows will be able to find. Select Browsable to Network Clients, as this feature will let you use the Windows Explorer menus to access your NAS as you would any other folder on your PC.

The other options I’ve selected aren’t especially secure. I want this NAS to be readily accessible to everyone, though, and I have a reasonable level of trust in my coworkers.

And we’re done! Just click Start on a Windows machine connected to your network, and in the Run text box (immediately over the Start icon) type \\YourNASnamehere and press Enter. Windows will connect to the NAS, and you can start dropping files in. Feel free to tuck the NAS out of the way. Mine isn’t even connected to a display, as everything we need to do can be handled in a browser on any machine on the network.

Sunday, May 18, 2014

SOLAR WATER HEATING BUYER'S GUIDE

At first glance the purchase of a solar water heating system might seem a little intimidating, enough so to often deter potential buyers from following through on their decision to save money and help save the environment. This buying guide takes you through some of the key factors you need to consider when purchasing a solar water heating system.
By reading this, you will come to realize that implementing solar water heat in your home or business is not as complicated and intimidating as you initially thought.
This buying Guide will cover the following topics:
  • How does solar water heating work?
  • Types of Solar water heating systems
  • Types of solar collectors
  • Determining how much water your household uses (what size system you require)

1. How does solar water heating work?

Solar water heating is an entirely different technology to solar powered electricity generation. Whereas solar power uses the suns energy to create electricity, solar water heating uses the radiating heat from the sun to physically heat water up.
A solar water heating system is made up of three primary elements:
  • Solar collector: This is an energy device which has been specifically designed to absorb solar heat radiation and transport that energy into the transfer medium or liquid passing through the collector.
  • Energy transfer medium: This is a medium that via the process of conduction or convection, transfers the heat that has been absorbed by the solar collector, into the water to heat it up.
  • Thermally insulated hot water storage vessel or geyser: Usually consisting of an inner lining made up of copper, steel or a polymer, this is the storage vessel, or more commonly, the geyser in which your water is stored and kept warm. Different geysers with different pressure systems are used in various circumstances, depending on the overall system design.
Solar water heating geysers are usually larger than your average household geyser as they are required to store the ENTIRE water allocation for each day.
Depending on your requirements, you can either use your solar water heating system to supplement the amount of heated water required from your conventional electric geyser, or you can use it to completely replace your electric geyser and provide your total hot water allocation for each day (recommended).
As far as the positioning of your solar water heating system is concerned, it can be stored on the roof, in the ceiling or in a regular closet as with a regular electric geyser. Ideally, you want to store your water storage vessel vertically, but if this is not a possibility, it can also be mounted horizontally without too much of an effect on the performance of the geyser.

2.    Types of Solar Water Heating Systems:

There are two main types of solar water heating systems, namely:
·         Direct Solar water  Heating SystemOpen circuit or direct systems: These types of systems circulate water directly to the geyser from the solar collector. Unfortunately, these systems aren’t anti-freeze resistant and therefore often not eligible for an Eskom solar water heating rebate if you reside in an area of the country that is susceptible to extremely cold temperatures. 
Image courtesy of sspluc.com

·         In-direct Solar Water Heating SystemClosed circuit or indirect systems: These are systems that contain a heat transfer medium that is circulated through the pipes within the system to heat the water and then returned to the solar collector for re-heating. These systems are more resistant against colder temperatures and are therefore recommended for use in the South African inland where frosty conditions are often experienced.


Image courtesy of sspluc.com

3.    Types of Solar Collectors:

As mentioned before, Solar Collectors are the actual solar water heating panels that absorb the heat from the sun and supply the heat to be used in the remainder of the system. There are two main types of solar collectors:
Flat panel collectors: These types of collectors tend to be a little more versatile as far as their positioning and placement goes. They can be mounted on the roof, inside the roof or even separate from the roof if need be.
 Vacuum (Heat pipe) / Evacuated tubes: These tubes function similarly to the way in which a hot water (coffee) flask does; by creating a complete vacuum inside the parallel pipes that make up the collector, which results in the water staying hot once heated.
Both the above systems are equally effective as long as they are used in the correct type of system. Have a look at some of the pros and cons of each system and then decide which will best suit you and your domestic solar water heating needs.

4.    Selecting the correct size solar water heating system:

The two variables that come in to play when determining the size of the solar water heating system that you require are the size of the total collector area and the size of the geyser/storage vessel that you require.
The general rule of thumb for calculating the size of your solar hot water heating system is that on average, each person in the house requires approximately 50 litres of solar heated water per day. Obviously, this can fluctuate depending on different people’s habits, but one should aim to use on average this amount of water.
Remember though, that different household tasks and appliances also utilize hot water. Below is a table that illustrates the average daily hot water consumption for a family of four:
Sizing example for a household of four people:
Daily hot water requirement
50 litres per person (200 litres)
Hand basins
5 litres per person per day (20 litres)
Dishwashing
3 litres per meal, assume 2 meals at home daily (24 litres)
Add compensation for heat loss due to cold water mixing
244 litres x 20% (48.8 litres)
No washing machine added

Total hot water requirement
292.8 litres per day
Table courtesy of eskomdsm.co.za

You see, it’s not that complicated

As you can see, the process of selecting a solar water heating system need not be any reason to deter you from actually going through with purchasing one. Your biggest considerations are what type and size of collector to utilize, and what size storage vessel/geyser to use.
If you require any further assistance, please do not hesitate to contact us. We have professional consultants at hand to advise you on exactly what you require and what type of system will create maximum benefits for you.

LED LIGHTS BUYER'S GUIDE

You can go green with LED lights and save money while also helping the environment. Who doesn't want a better way to improve their home and become more eco-friendly? The recent innovations of LED lights make them even more efficient and beneficial to anyone looking to go green in their homes, offices, cars, bicycles and more. Once you learn more about how LED lights are helping people go green, you'll wonder why you didn't make a switch sooner.
Here are some of the ways that LED lights help you go green:
• They use less energy.
• They last longer and thus don’t need to be replaced every few months.
• They can replace most CFLs and high powered lights installed in your home.
LED Lights are now more affordable and more readily available than ever before, making it easier to get exactly what you need today. You can find them in a variety of colours and styles as well as shapes to meet your needs and even your personal d├ęcor style. It's that easy!
This buying Guide will cover the following topics:
  1. How do LED Lights work?
  2. Selecting the correct size.
  3. What colour is best for me?
  4. Types of LED Lights.

How do LED Lights work?

LED stands for Light Emitting Diode and this is a light source that is used in solar powered products. You've probably seen these before even if you did not realize what you were seeing. There are many advantages to LED lights over incandescent and halogen lighting sources. To understand what these advantages are, you need to understand how the LED works.
First, the LED contains a semiconductor diode. This means that it has a material that is capable of conducting electricity. With an incandescent light, it would operate differently. The current is sent through a filament which is different from the LED principle.
If you are new to the world of electronics and LED lighting, you may be wondering what a diode is and how it works? To put it in layman’s terms, a diode is a one-way route for electric current to flow. Basically a diode is a one way valve that allows the current to run one way but not in the other.
The way a diode works can seem confusing to someone who is not familiar with electricity. But to keep it simple, a diode has two electrodes that work like semiconductors. There is a P or positive electrode which is called an anode and an N or negative electrode which is called a cathode. The cathode receiving a negative charge compared against the anode allows the current to flow. If the electrodes are similarly charged, the current will not flow.
Diodes serve a few different purposes in electronics. One way to think of a diode is as a check valve or switch for the electric current. If you think of electric current as water and the diode a ball check valve, it makes it easy to understand a diode. When a diode is used, the “water” can flow upstream but not downstream, or downstream but not upstream. Diodes can be reversed but will remain a one way path. Simply put, the water can flow but if it tries to flow the wrong way the diode will block the path.
Diodes can be used to convert an electric current from Alternating Current (AC) to Direct Current (DC). This process is referred to as rectification and requires a rectifying diode. This is generally used with low voltage electric current applications. To increase the voltage flowing through, you can bridge diodes to create more power.
Diodes can also be used to turn a circuit off or on, using a switching diode. Did you ever wonder how different radio station bands are reached and kept separate? A band diode is used to switch between high frequency band signals.
Diodes are also used in producing signals, light and microwave frequencies. Light emitting diodes are known as LED, and probably most commonly used in computers, clocks, solar lighting and electronic panel displays. These days there are LED televisions and even modern Christmas lights as well.
Simple electronic diodes are used in so many areas of modern life that you would be surprised at the many applications of diodes you will find as you move through a normal day. When you flip a light switch, you have used a diode. A digital clock shows you the effect of a diode. How about your cell phone, iPod, laptop, remote control, and big screen television? Each and every one of these devices uses diodes.
Now that you know what a diode is, understanding electronics is probably going to be a much easier task. Electricity is all about current and the route it takes to bring the voltage to the necessary device. When you understand the basics of what the diode does, it helps you to understand LED lights and other uses as well.

Selecting the correct size

The general rule of thumb, when selecting the wattage of your LED light is to calculate ten percent of your current light bulb wattage e.g. 60W = 5/6W LED Light
Fittings:
B22 and E27 are most like normal househould fittings.
  1. B22 – Bayonet 22mm diameter 220V input
  2. E27 – Edison Screw In 27mm diameter 220 volt input
  3. E14 – Edison Screw In 14mm Diameter 220Volt input
  4. GU10 – 2 Pin Downlighter Fittings 220V Input
  5. MR16 – 2 Pin (thin) Downlighter Fittings 12V AC
  6. MR16 – 2 Pin (thin) Downlighter Fittings 12V DC

What colour is best for me?

LED Lights are available in a variety of colours. The reds, blues and yellows etc, are self explanatory but there are two white options that may be confusing. Pure white refers to a stark white colour similar to fluorescent tubes, while warm white refers to the colour normally found in household bulbs.

Types of LED Lights

What are you waiting for?

Don’t be left behind as LED lighting grows from a trend among the purely eco-conscious to widespread adoption internationally. 
If you require any further assistance, please do not hesitate to contact us. We have professional consultants at hand to advise you on exactly what you require and what type of system will create maximum benefits for you.

SOLAR POWER BUYER'S GUIDE

Selecting the correct solar panel products for your home can be an extremely daunting task for the average person. If after reading this buying guide you are still not entirely sure which products you require in order to start using solar panels in your home, then please do not hesitate to contact us now so that our experts can assist you.

South Africa has an average of more than 2,500 hours of sunshine a year; with the total radiation reaching the land area amounting to roughly 1 kilowatt per square metre at noon on a sunny day. This is more than double the solar radiation output of Europe, making it one of the highest in the world and perfect for home solar panels in South Africa. 

This buyer's guide will cover the following topics:
* How do Photovoltaic solar panels (PV) systems work? 
* Types of home solar panel systems
* Types of solar panels
* Determining what size solar panel system you require
* Solar panel installation
* Benefits of a Photovoltaic solar panels (PV) system

1.    How do Photovoltaic solar panels (PV) systems Work?

PV Solar panels are made up of a series of cells that convert sunlight directly into electricity (direct current). These cells are made from semiconductor material, usually silicon. Solar panel cells operate according to what is called the photovoltaic effect, ('photon - light, 'Voltaic' - electricity). In the photovoltaic effect, sunlight (or photons) strikes the surface of semi-conductor material, such as silicon, and then the energy penetrates the cell and dislodges electrons from the material's atoms. Certain chemicals added to the material's composition help establish a path for the freed electrons. This creates an electrical current.
A fully functional home solar panel system is made up of the following essential components:
  • Solar panels: These are often connected together in an array to provide higher power outputs and DC voltages.
  • Solar storage batteries: The electricity generated through the home solar panels is stored here.
  • Charge controller/ regulator: These prevent excessive discharge or overcharging which could damage the solar storage battery.
  • DC-AC inverter: Solar panels produce direct current (DC) and most appliances and equipment are designed to be powered by alternating current (AC). An inverter is used to convert the direct current from the PV solar panels or battery into alternating current which we can use in our homes.
It is important to note that ordinary incandescent bulbs should not be used with a PV solar panel system for the home as they drain power from the batteries much faster than energy efficient LED light bulbs will.

2.    Types of Solar Power Systems

There are two types of Solar Power Systems that can be used in the home or the office, namely:

2.1 Stand-alone Solar Power Systems

These systems are designed to operate independently from the grid (Eskom). 
Since there is no electrical energy storage (batteries) in direct-coupled systems, the load only operates during sunlight hours when the PV solar panels are hit by the sun; making these designs suitable for common applications such as ventilation fans, water pumps, and small circulation pumps for solar thermal water heating systems. 
For the above reason, it is advisable to have solar batteries installed in the solar panel system so that power can be stored and used when there is no direct sunlight.

2.2    Grid-connected Solar Power Systems

Grid-connected PV solar panel power systems are designed to operate in conjunction with the grid (Eskom’s power supply). The main component in grid-connected solar panel systems is the inverter. The inverter converts the DC power produced by the PV solar panels into AC power which is consistent with the voltage and power quality requirements of the grid and automatically stops supplying power to the grid when the utility grid is not energized. 
A bi-directional solar panel interface is made between the solar power system’s AC output circuits and the electric utility network. This allows the AC power produced by the solar panel system to either supply on-site electrical loads or to feed power back into the grid when the home solar panel system output is greater than the demand of power being used within your house at any time.
At night and during other periods when the electrical requirements in your home are greater than the solar panel system output, the balance of power required in your home is taken in from the electric grid. This safety feature is required in all grid-connected systems and ensures that the solar panel system will not continue to operate and feed back into the utility grid when the grid is down for service or repair.

3.    Types of Solar Panels

There are 3 types of Solar Panels available, namely:

3.1 Monocrystalline Solar Panels

These solar panels are made of a large crystal of silicon. Monocrystalline solar panels are the most efficient with regard to absorbing sunlight and converting it into electricity; and thus do better in lower light conditions than other solar panels.

3.2 Polycrystalline Solar Panels

These are the most common solar panels on the market today. They look a lot like shattered glass as consist of multiple amounts of small silicon crystals. Polycrystalline solar panels are slightly less efficient than Monocrystalline solar panels but are less expensive to produce.

3.3. Amorphous Solar Panels

These panels consist of a thin film made from molten silicon that is spread directly across large plates of stainless steel or similar material. Amorphous solar panels are less efficient than the other two types of solar panels but are also the cheapest to produce. One advantage of amorphous solar panels over the other two is that they are shadow protected, meaning that the solar panel continues to charge while part of its cells are in a shadow. These work great on boats and other types of transportation.

4. Determining what size system you require

If you plan on tying your solar panels into the grid, then one way going about it is to just buy as many solar panels as you can afford right now and then simply sequentially adding panels to the system as you are able to afford them over time. Eventually you could end up with a fully operational solar panel system that is completely independent of the grid and providing you with free electricity.  

If you wish to completely disconnect your home from the grid, then there are a few steps that you will need to follow in order to find out about how many solar panels you will require to generate 100% of the energy used in your home:
    • Make a list of all the electrical appliances that you use in your home, how many watts each uses and estimate how many hours per day you use them.
    • Multiply the total watts by the hours used for each appliance. So for example if you use a radio for 2 hours a day while working out and it uses 14W, then you would multiply 14 by 2 to get a total of 28watts per day for the radio. Once you have done this for each item, add them all up to get the total sum of watts that you use in your house on a daily basis.
    • Determine the average amount of sunlight hours your solar panels will receive a day.
    • Now divide the total amount of watts used per day as you figured out in step 2, by the average amount of sunlight. If you use 3000 watts per day in your home and the average sunlight is 4.3 hours, then you would divide 3000 by 4.3.
    • This means you will need at least 698 watts of solar panels to get enough solar energy to power your entire house.

5.    Solar Panel Installation

NB. If you are not technically inclined, then it would not be advisable to attempt installing a solar panel system in your home without any assistance from a professional.
There are three ways in which to install solar panels in your home, namely:
  • Ground Mounted Solar Panels
  • Roof Mounted Solar Panels
  • Thin Film Solar Panels

5.1 Ground Mounted Solar Panels

Ground mounted solar panels are fixed to poles that are cemented into the ground. There are a couple different options you can choose from if you decide to go with a ground mounted solar panel system, namely:
  • Static Mounted System
The most cost efficient ground mounted solar panel system is to just use a setup that points the solar panels towards the most effective direction for maximum sunlight exposure.
  • Active Solar Tracker
Solar Trackers have an optical sensor that follows the sun throughout the day and maximizes the energy absorbed by the solar panels.
  • Passive Solar Tracker
This is a slightly cheaper option than active solar trackers. A passive solar tracker system uses the sun's heat to move liquid from side to side within the tracker; allowing gravity to turn the solar panels to follow the sun without the use of motors, gears or controls. By using either type of solar tracker you'll help your solar panels get as much sun as possible throughout the day as it automatically points them in a perpendicular direction to the sun.

5.2 Roof Mounted Solar Panels

Solar panels can be mounted on many different types of roofs. Shingle roofs are the easiest to work whilst tiled roofs can be a bit more challenging.

5.3 Thin Film Solar Panels

Although thin film solar panels don't absorb the sunlight with as much efficiency as other solar panels, there are numerous benefits to installing these types of solar panels:
  • Unlike Monocrystalline solar panels, you don't have to mount the thin film solar panels on your roof. The thin film panels are literally glued onto the roof which means no holes. Putting holes in your roof can void your warranty and even damage it if it’s not done correctly.
  • Also, thin film solar panels don't weigh as much as other panels that contain large amounts of silicon with structural support.
  • Thin film solar panels work better than conventional panels in very hot climates. They also do a better job of producing energy at the beginning and end of the day during times of non-direct sunlight.

6.    Benefits of a PV System

  • Solar panel power is a renewable form of energy, i.e. it won't run out like oil, coal and gas.
  • Once the initial cost of purchasing the panels is paid in full, the electricity it produces for the remainder of the solar panel system's lifespan (25 – 30 years) is absolutely free!
  • Photovoltaic solar panels can provide electricity for lighting and entertainment during blackouts
  • Solar panel systems provide a safer lighting option than candles and paraffin
  • There are no harmful emissions caused either through generating electricity or inside the home
  • The photovoltaic solar panel industry can provide up to 400% more jobs than the conventional energy industry

Conclusion

Yes, it can seem daunting having to select the correct solar panels and accompanying products to purchase for your home, however this guide should point you in the right direction. If you require any further assistance, please DO NOT HESITATE to contact us so that our experts can help you choose the correct solar panel system for your home.

The Ultimate Beginner’s Guide to Energy Saving Light Bulbs

Energy Saving Light Bulbs
Five years ago I bought my first LED light bulbs.  They were to replace halogens in my bathroom.  I spent too much money on not enough lumens and way too many kelvin.  You know what I mean?
No?  Perfect. Let’s make a deal?!
If you spend ten minutes reading this post I promise you that by the end of it you’ll understand how to buy a low energy light bulb.  In return I’ll try not to bore you senseless.
Ready?  Let’s do this.  With five simple questions.

1) What fitting do you need?

This is simple, but you really don’t want to mess it up.  
Although there are literally hundreds of light fittings in existence, your home probably only has a couple.  I’ve got two in my ceiling fittings, a couple more in table lamps.  In the image below there are some common ones for the UK and US.
bulb fittings
‘B’ is for Bayonett, it’s a bit of a British Empire thing.  ’E’ is for Edison Screw, dominant in the US thanks to Thomas.  ’GU’ is for, gee you really need to get yourself a life a if you know what ‘GU’ means.
You don’t need to know what they mean.  But if you scribble down the fittings before you start shopping for bulbs not only will they fit, they’ll be the right voltage too.

2) What shape bulb do you want?

Bulb shape is not just a question of liking the look of a bulb, it is about how it throws light.  The design of the bulb determines what direction the light goes, so you need to consider what you want the bulb to do.
bulb shape
There is literally an alphabet describing different bulb shapes, but since I promised not to bore you I’m just not going to go there. All you need to do for shape is use your common sense.
For a ceiling pendent you might want an ‘omnidirectional’ bulb like the arbitary, stick or spiral shape.  For a lamp you might need a candle shape with a broad spread.  And if you are putting a spot into a recessed downlight you’ll need a reflector with an appropriate beam width for the context.
A bulb that throws the wrong angle light can be really annoying, so do take the time to contemplate the shape before you buy.

3) How bright does it need to be?

It is no longer enough to think about bulb brightness in terms of watts.  That was fine when we only had incandescents, but now we need to start thinking in lumens.
This is particularly the case when buying LEDs, because the use of the term ‘replacement’ is can be abused by bulb re-sellers, and occasionally by lesser manufacturers too.  The following tables are a rough explanation of how many lumens you get from your watts for different bulb technologies for a standard fitting.
Now I’m very sorry to do this, but I had to make two charts to explain this properly.  One for our readers in the low voltage (120V) countries like the US, Canada, Brazil and Japan.  And a second one for readers in high voltage (240V) countries, that’s the rest of the world.

The American Lumen:

If you live in the US, or anywhere else with a lower voltage grid, please look at this first chart.  If you live elsewhere skip straight to the second.
Lumens US
At the top of this chart you have the brightness of the bulb in lumens.  This is the number you need to start thinking in.
Let’s say you’re in the US and want to replace an old 60W bulb and get a similar amount of light.  Then you know you’ll need to get at least 800 lumens in order to match the brightness of the old 60W .
Got it?  If you know your lumens, you won’t be mis-sold a ‘replacement bulb’ that isn’t bright enough.

The High Voltage Lumen (UK):

In the rest of the world grids have higher voltage, meaning that lumen equivalent for standard incandescents is different.
Lumens needed
At the top of this chart you have the brightness of the bulb in lumens.  This is the number you need to start thinking in.
Let’s say you’re in the UK and want to replace an old 60W bulb and get a similar amount of light.  Then you know you’ll need to get at least 700 lumens to get a similar brightness to the old bulb.
Knowing your lumens means you will get the brightness you want, and avoid being mis-sold ‘replacement bulbs’.

A quick word on spotlights:

Just spot me a second here.  Both the two charts above are designed to help you replace a normal lightbulb.  When it comes to spotlights you can often experiment with going for fewer lumens.  In our bathrooms I have replaced 700lm halogens with 320lm LEDs and actually prefer the light.  The result is a 90% energy use reduction per bulb.

4) Do you want warm or cold light?

This question might sound complicated, but it is dead easy and one of the great things about LEDs.
The temperature of light can be measured in terms of ‘kelvin’.  Very orange light has a low number of kelvin, for example a candle is about 1,500K.  Daylight is much colder, often above 5,000K.  Here is the scale.
kelvin scale lightbulbs

When it comes to household light bulbs the temperature choices are very simple.  Most people simply want what is called ‘warm white’ (2,700k) to replicate the warm, slightly yellow glow of an old incandescent or halogen.
In a kitchen, bathroom or other situations you may prefer a slightly less yellow light, sometimes called a natural white (3,000K). You may want to try cool white (4,000K).  Or for a very specific style (5,000K).  Anything above that starts to get a little blue.
This type of temperature choice is mostly associated with LEDs.  If your home has a quite modern style you should definitely consider trying some cooler temperatures, as they can look great in the right context.

5) Are LEDs good value yet?

Compact fluorescent (CFLs) bulbs are now so cheap that a CFL can pay itself off with energy savings in just months for a well used bulb.  I personally quite like CFLs in the right context, but if you want instant light, dimming or cooler light they aren’t great.
LEDs on the other hand are gradually overcoming many of these problems.  The main issue with LEDs at this point is their upfront cost.  This is particularly true for 75W and 100W replacements (I’m waiting for prices to drop).
With this in mind let’s crunch some numbers and see how the payback is for LEDs.  In the following chart I estimate how quickly energy savings will recoup the cost of replacing a 60W incandescent with a 10W LED that costs $10, assuming the bulb is used for 2 hours each day.
LED payback times
Because of the huge difference in the prices of electricity the $10 outlay for the LED pays itself off in anything from 9 months in expensive Denmark to three and a half years in India or China, where electricity is cheap.
Of course a 60W LED for $10 is still quite cheap.  If it costs you $20 to get such a bulb you’d need to double these numbers.  On the other hand if you are using the bulb 4 hours a day, then you should halve them.  What does this mean for you in practical terms?
  • Cheaper LEDs payback faster
  • Payback is faster where electricity is expensive
  • The more you use a bulb the faster the payback
  • Replacing CFLs with LEDs is not yet cost effective
In most cases the one year running cost of an incandescent bulb you use regularly (>2 hours a day) is greater than any drop in LED prices we are likely to see.  So it makes sense to switch when you see a decent value bulb.  However, if you don’t use a bulb much (< 1 hour a day) you may want to wait for falling prices.  Especially in the 100W replacement range which are still extortionate.
I have one incandescent left in my loft that I’d be lucky to use for 10 hours a year.  I’ll probably only switch it if it blows.

5 Steps to Buying a Energy Saving Light Bulb

If you’ve made it this far you now know a lot about light bulbs.  Because I promised not to bore you I’ve decided not to discuss dimming (read the labels), color rendering (above 80 please) and bulb lifespan (buy a known brand).
Let’s just recap the five steps:
  1. Fitting: Write down the code
  2. Shape: Decide on the best shape
  3. Brightness: Get enough lumens!
  4. Temperature:  Warm or cool?
  5. Cost: Look for good value bulbs
Like I said in the introduction, I bought my first LED five years ago and only really got the first of these five steps correct.  But things have changed an awful lot in five years, and LEDs are now becoming a really sensible option.  CFLs remain excellent value due to their low prices and running costs, but you can’t always get the light you want.
If you have never bought LEDs before I highly recommend trialing a single bulb, or spotlight, first before buying too many. LEDs are not cheap and last a long time, so you want to be sure about fitting, shape, lumens and kelvins before going all in on them.  I also recommend looking for specials on known brands or having a money back guarantee up your sleeve.
Here in the UK I’m on the lookout for decent 10W LEDs around the £10 mark. This Verbatim LED 10,5 W  verbatim is a great deal for £9.99.  Or something like this 10 Watt LED (or in a screw fit).  I’ve just bought this Philips Master because I’ve always liked the look of it and saw a big price drop .  For bathroom or kitchen spots I prefer LEDHUT.
Looking over the pond to the US I’m almost jealous. You guys get similar 10W LEDs for $10.  This great 11W LED Dimmablefrom Phillips (complete with Energy Star rating) for $15.  Interesting slim style bulbs. Your LED spots  are cheaper too.  And you can buy remote controlled color changing LEDs  for just $13, which is not boring!!
If you made it the end, thanks for reading.  I wish you much success with your LED hunt and hope you get the right fit, shape, brightness and temperature at a decent price.  Most importantly I hope you prefer the light of your new bulb, as that is the main test of success.