What does a solar system include?
A solar system (otherwise known as a photovoltaic or PV system) consists of solar panels and a form of inverter/s.
There are two main types of inverters: a string inverter (that is installed on a wall with all solar panels connected to it), and microinverters (that are attached to the back of each solar panel). Inverters convert the electricity generated by panels into 240V AC power, making it suitable for household use.
The number of panels in your solar system will depend on its size, which is usually determined by the size of your roof, and the energy requirements of your household.
What size solar system does my home need?
To answer this question requires firstly answering three other questions: how much power does your house use; how much space do you have for solar panels; and what are your goals?
If your goal is to operate your home off-grid (i.e. with no connection to the main electricity grid, aka the network that carries electricity from power stations across the country to your house) you will need a larger more complex solar system than someone who is interested in using solar in conjunction with electricity from the grid.
Most solar-powered homes in Australia use a combination of solar power generated on their rooftop, and electricity supplied by the grid. The grid connection is used to supply power at night (when the sun isn’t shining!) and times when the solar panels can’t generate enough power, such as on low-sunlight days.
You can get an idea of the best size system for your house by using online calculators such as Solar Quotes and Solar Calculator. A good solar provider will thoroughly assess your energy needs, and make a recommendation of the best system for you.
Why doesn’t everyone operate their house off-grid?
There are three main reasons that most solar owners remain connected to the grid: cost, lifestyle, and space.
Many homeowners simply don’t have the roof/land space for a large enough system to go off-grid (which requires a battery in addition to solar panels, and often a backup generator), or the upfront finances to invest in a system of this size.
Homes that run off-grid also need to be particularly energy-efficient and the load demand needs to be well-managed throughout the day.
Do I need a battery?
A battery (or batteries) is an optional additional component of a solar system that stores power to use at night and on low-sunlight days. A battery will greatly enhance your solar system, ensuring you can use solar power at home even when the sun isn’t shining, but it does come at significant extra cost.
Batteries come in a range of sizes to suit various household needs. Without a battery, solar powered homes draw on grid electricity when their panels are not generating enough power to run their household. Conversely, any excess power their solar system creates that cannot be used immediately by the household is fed back into the grid and compensated via a ‘feed-in tariff’ (FiT).
Director of BREC Energy Luke Serdar generally advises customers observe how their solar system functions before investing in a battery. ‘We’d install solar first, educate the client on how to get the most out of that investment, assess the data over the next 3-12 months and then revisit the client to see whether a battery is worth it for them,’ Luke explains. ‘We’ve repeated this process twice with some clients; we’ve installed solar first, waited a year, installed a battery, waited another year, and then installed another battery. Each step of the way we’re reassessing the data, all just to make sure the client isn’t wasting money.’
How much does a solar system and battery cost?
As an estimate, director of BREC Energy’s Luke Serdar says a good quality solar system (including installation, but depending on the complexity of the install and products used) costs around:
– $1,800-$3,000 per kW of solar
– $1,000-$2,000 per kWh of battery storage
As a case study, occupational therapist and maker Catherine Spillane spent $12,250 (price inclusive of a $3,750 rebate, available at the time of purchase) on a 12kW solar system (with premium panels designed for high salt mist locations) installed in her Anglesea, Victoria property in 2021. She also purchased a battery at a later date for $6,500 (price inclusive of a $3,500 rebate, available at the time of purchase).
Spillane’s solar system and battery covers 70 per cent of her power needs across her family home, pool, and separate holiday house that’s occupied four nights a week. The property is entirely electric, and the outstanding power bills are approximately $50 a month.
The national Small-scale Renewable Energy Scheme (SRES) provides a financial incentive (aka rebate) for Australians to install solar power, and some states offer additional rebates.
Whenever you see an ad for solar power, the advertised price will usually already include the rebate. The installer claims the rebate on your behalf when you buy a system, so you only pay the advertised price.
How long does solar take to ‘pay itself off?’
Accurately predicting the time it takes for an investment in solar to pay is complicated, as it depends on many variables, including your available sunlight, electricity prices, power use, and solar feed-in tariffs.
Feed-in tariffs are basically a credit that solar system owners receive from their electricity retailer in return for each kilowatt-hour (kWh) that they generate and feed back into the grid (as organised by their solar provider).
Reports by both the Australian Energy Council and Alternative Technology Association show most 5kW systems will achieve payback in 3-7 years, depending on their location.
How do I choose a solar installer?
A quality solar system starts with a quality installer. To director of BREC Energy Luke Serdar, that means finding a company that’s passionate about their work, uses well-made solar panels, and will take the time to educate you about your needs.
Rather than Googling ‘solar installers’ and getting thousands of results, speak to friends and family who have had solar installed for their recommendations, or turn to social media.
‘It might sound a bit of an odd perspective, but I feel like the installers that have a good social media presence and consistently post about their work are the people you want to talk to,’ says Luke. ‘Avoid the salespeople and steer toward the small businesses that have the person educating you with what’s right for your home or business, and also have on-the-tools experience. They’re the ones who really know how solar works.’
What can I expect when contacting a solar installer?
When you contact a solar installer, they will either visit your property in person or view the site via satellite images to determine its orientation, available space, and requirements.
‘For the experienced installers, you know the style of places which require a visit and which don’t… If the house looks tricky, a site visit is paramount for getting the quote correct,’ explains BREC Energy director Luke Serdar.
A good solar installer will also request to see up to 12 months of electricity bills for your household (if available), to thoroughly understand how much energy your household uses, in all seasons of the year.
From there, Luke says it’s all about educating customers about what’s involved, managing expectations, and determining the best system for them. ‘Even if you only have one roof face to play with, I feel like it’s super important for the client to know the limitations or benefits for panels facing a certain direction.’
Do solar panels differ in quality? What products are the best?
Yes, solar panels differ in quality, which means some will last longer than others (which is important to consider from both an environmental and financial perspective).
Solar panels from quality manufacturers will generally have a longer replacement warranty than those that don’t. Director of BREC Energy Luke Serdar says entry level panels will have a replacement warranty of around 12-15 years, and the best have a replacement warranty between 25-40 years.
Solar panels also have a performance warranty to protect from degradation, which generally happens at a rate of around 0.5 per cent every year. Degradation is unavoidable due to normal wear and tear, exposure to UV rays, and adverse weather conditions. ‘The extreme temps we get here in Australia really require quality products to avoid failure,’ says Luke.
Luke says solar panels sold in Australia usually guarantee delivering at least 80 per cent of their rated power after 25 years. Panels can also be recycled at the end of their life through companies such as Ecoactiv.
Do I need to do anything once my solar is installed?
Running a solar system requires regular engagement and adjustment for optimum performance. In fact, director of BREC Energy Luke Serdar says educating customers and conducting a thorough handover is the most important piece of the puzzle.
Most importantly, to get the most out of their system, customers should adjust their household habits to use solar power when it’s available (i.e. when the sun is shining!). This can be achieved by making small adjustments to your household routines, like setting your dishwasher and washing machine to timers to be used in the day when solar is being generated.
A good solar provider will set you up with a monitoring system that will show you just how much electricity your solar system is generating, and how much power your household is using at any given moment. In all likelihood, you’ll be amazed at how quickly you become aware of your energy consumption, and the miraculous benefits of rooftop solar!
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