Generate your own electricity the sustainable and environmentally-friendly way with solar power.
In a country that gets as much sun as Australia, it's no wonder that household use of solar power is becoming increasingly popular. Though they were once seen as too expensive, solar photovoltaic (PV) systems are now an affordable choice for Aussies who want to reduce their power bills and generate their own environmentally-friendly electricity.
There are many benefits to installing a solar power system in your home. Australia has the highest solar radiation per square metre of any continent and solar power is a sustainable option that collects free energy from the sun and converts it into clean electricity. It's also a great way to reduce your carbon footprint by avoiding more traditional forms of energy powered by fossil fuels.
Once installed, solar systems can be expected to last for 20 years or more and they require little in terms of regular maintenance. But best of all, the electricity they generate is free, so those increasingly expensive power bills can be a thing of the past.
Solar power technology is far from a modern development, with efforts to harness the sun's energy recorded at least as far back as the 7th century BC. More recently, however, French scientist Alexandre-Edmund Becquerel discovered the photovoltaic effect in 1839. This effect explains how sunlight can be used to generate electricity.
Further discoveries and inventions followed, but it wasn't until 1954 when three scientists from Bell Labs in the United States developed the silicon photovoltaic cell that significant progress was made. This was the first solar cell capable of providing efficient power with real-world applications.
As technology advanced, solar power gradually came to be seen as a viable option for generating electricity. Today, more than one million Australian households have solar panels installed and that number will continue to grow as prices come down. The Federal Government's Energy White Paper, released in November 2012, projects that by 2035 solar PV systems will provide 17 per cent of Australia's energy and 29 per cent by 2050.
How do solar panels work?
Solar PV panels are usually fitted on the roof facing in a northerly direction and at a certain angle to maximise their exposure to the sun. The panels contain PV cells, also known as solar cells, which convert the sun's energy into direct current (DC) power. There are no moving parts involved and the solar panels are usually connected to the mains power supply through an inverter so the DC electricity can be transformed into alternating current (AC) electricity suitable for everyday household needs.
image courtesy of vpe-solar.com
How much can I save with my own solar power system?
According to the Clean Energy Council, the cost of solar panels has been falling by about 45 per cent per year. However, installing a solar PV system is still a significant investment, which is why there is government assistance available to help cover the cost (read available assistance section below for more information).
But because solar systems let you generate your own electricity, over time the money you save on power bills will help you pay for your initial investment - this is known as 'payback'. Payback times are influenced by a number of factors, including the size of your system, your energy consumption patterns, your eligibility for government assistance and even the weather.
According to Living Greener, the average Australian house consumes around 18 kilowatt hours (kWh) per day, so a 1-2kW solar system displaces an average of 25-40 per cent of your average electricity bill, which could translate to a significant saving. To get a more accurate estimate of the saving, use your electricity bills to add up your annual consumption or find out how much energy your household consumes each year.
Type of system and supplier
According to the Clean Energy Council, before choosing the right system for your situation, you need to ask yourself why you're installing solar power in your home.
Before you start
- Do you want a system that will partially offset your energy consumption for 5-10 years before requiring a system upgrade?
- Or do you want a system that will completely offset your household's electricity use for the next 25 years?
To work out what size system you require, study your electricity bills. From these you can calculate your average daily electricity consumption and the average amount of electricity your solar PV system needs to produce to meet your needs. The unshaded area available for the installation of your panels, along with how much you are prepared to spend, will also need to be taken into consideration.
Getting quotes from several accredited installers will help you compare costs and discuss any questions you may have. Another important decision to make is whether you'll need a grid-connected system, which interacts with the main power grid, or a stand-alone system that has its own electricity storage. If you live in an area where connecting to the main electricity grid is not possible, or where connection costs are expensive, stand-alone systems are a viable option.
These systems are, however, more complicated and expensive. They involve more components and require more maintenance and you'll also need a battery bank installed in accordance with Australian Standards to store electricity.
If you want a grid-connected system, it's up to your electricity supplier to agree to connect you. Some companies let you feed the excess electricity your system generates into the electricity grid and then take the payment for selling your electricity off your power bill.
Grid-connected systems also require an inverter to convert the DC electricity produced by the solar panels into AC electricity for everyday household use. The Clean Energy Council has a list of all grid-connect inverters that meet Australian standards. Check with your installer to ensure you're getting the right inverter for your needs.
Be aware there may be additional costs involved, including a new fuse box or a grid-interactive electricity meter. Also, check that your installer/designer is on the Clean Energy Council's list of accredited installers as this could affect your eligibility for financial assistance, rebates or insurance.
Make sure your panels meet Australian standards. The Clean Energy Council has an up-to-date list of all solar panel and inverter models that meet Australian standards.
Decide on a budget and location to install the panels. Solar PV panels come in different wattages and the main factors to consider when buying are how much you want to spend and whether the panels will fit in the space available. Each solar panel is approximately 1.6 metres long and 0.8 metres wide. A 1.5kW solar panel system requires around 12m² of roof space, though this will vary depending on the type of panel you use.
Think about the placement of your panels. Your installer will also take into account the best position and mounting options for your panels so they get the largest amount of direct sun. Fixed panels should face north for maximum efficiency and, if on a grid-connected system, the inverter needs to be located as close as possible to the panels to decrease power loss in the cables that connect them.
Think about the future. Shade is the enemy of solar systems, so make sure any trees or buildings aren't likely to block the sunlight that gets to your system in years ahead. You might want to ask your installer to ensure bypass diodes, which let some electricity flow around the panel if it becomes shaded or damaged, are incorporated in the system.
Finally, get a system design and specification from your installer and make sure you also ask about the period covered by any warranty. The Clean Energy Council's Consumer Guide to Solar PV features a wealth of information to help ensure your solar installation goes smoothly.
Financial assistance is available to take some of the sting out of the cost of going solar. Small-scale Technology Certificates (STCs) offered as an incentive to install renewable power can save you thousands on the cost of a new system.
Additionally, find out whether an electricity feed-in-tariff is available where you live. If it is, find out the amount you will receive for any electricity you generate and feed back into the grid and whether you will be offered a gross or net feed-in-tariff.
Under a net feed-in tariff, you receive a premium for any solar energy you generate that goes back into the grid. Under a gross feed-in tariff, you are paid for every unit of electricity generated by your system, regardless of whether it is fed back into the grid or is used by you. Apply to your electricity retailer to receive a feed-in tariff.
How to maintain your system
Once installed, solar PV systems require relatively little maintenance. Your installer will outline any safety procedures and show you how to monitor the system.
The panels will need to be cleaned occasionally in order to maintain efficiency and if you're doing any gardening, don't plant any tall trees which may one day shade your panels.
Your inverter should have a data display so you can monitor how much energy your system is generating. If you'd like more detail on how your system is performing, there are monitoring systems available that let you keep a close watch on power generation and act immediately if it stops working. But remember, if there's ever something wrong with your system, contact your installer rather than interfering with the system yourself.
Once your solar PV system is in place, you can rest safe in the knowledge that you'll be powering your home in a sustainable and environmentally-friendly way. And best of all, you'll be saving money along the way.
Which way should solar panels face?
North. That is the ideal direction that solar panels in Australia should face for maximum power. The sun rises in the east then moves due north until midday when it travels west to set. If your roof doesn’t face north, then you still have options. If the roof faces north-east or north-west you will only lose 3-4% of the power, so not enough to make a difference.
If your roof faces east or west, then you could lose up to 15-20% of your power, which is a significant dent, and should have you wondering whether this will be worth the invest. However, you will still generate a significant amount of power, so if you’re a light user you should be fine. If your roof faces south, south-east or south-west then you will lose a significant amount of your solar potential. In some cases, it is still worthwhile installing panels, but this should really be discussed in detail with your solar provider.
How many panels do you need for your home?
This will depend on the size of your home and your energy usage, and also on the amount of money that you want to spend. If you’re planning on getting a feed-in solar plan, and selling your excess energy back to the grid then you would be better off purchasing as many panels as your budget will allow.
In general though, it is usually wise to get enough panels to cover your home usage and take any resale as a bonus. So how do you know how much you need?
Well, solar panels are often measured by their 'peak output', this is basically the amount of electricity that the system will produce on a sunny day. It is most commonly measured in Kilowatts (kW). So a 1.5kW solar panel will produce 1.5kW at its peak.
The best way to work out what system you need is to review your past usage. Your bill should give a summary of your usage in kilowatt hours (kWh). This is basically a measure of how many hours of peak power your system produces. So it is entirely possible for a 1kW solar system to produce 5kWh of energy. It simply means that your 1kW system produced five hours of peak power. Energy usage is measured in kWh and so will your solar panel system.
A simple method of determining your system requirements is to take your energy usage for the year and divide it by 365, which should give you an idea of your average daily usage in kWh. However, this is just to give you an idea of system requirement. If you are seriously thinking of getting solar panels installed, you should speak with a qualified solar professional who will help ensure that you find a system that fits your needs.
On-grid and off-grid.
There are two basic types of solar system, on-grid and off-grid. They’re quite self explanatory really. On-grid means that your system is connected to the energy grid, which could allow you to sell your excess power back to the grid. Off-grid means that your system is stand alone, and you’re not connected to any other units. Finding out which type of system is best for your home is a tricky business, and so we’ve created full guides to each type of system, which you can view by clicking the links below.
Can I get paid for the energy that I produce?
If your solar system is grid connected, then it may be possible for you to sell your excess energy back to the grid. You do this through a feed-in tariff, which means that you feed-in your electricity to an energy retailer, who re-sell it to other customers across the country.
Are you entitled to rebates?
Another financial benefit of solar power is the energy rebates that may be available to you depending on your state and solar setup. Solar rebates are a tricky thing, and they tend to change quite frequently, so we’ve devoted an entire article to help you understand and get the most out of them. Follow the link below to see if you could save money on your solar panel system.