Perth WA Best Solar PV system deals

Find the best solar power deals in Perth, WA

by James Martin II on February 20, 2012

in Solar and Renewable Energy Policy,State Government solar feed-in tariffs,WA

Perth is WA’s biggest city, and a great place to install a solar power system. With electricity rates rising, solar installation prices falling, and significant potential up-front financial subsidies through the federal government, now is a great time to find deals on solar power systems in Perth.

Why is Perth a good place for solar power?

Financial benefits of the Perth sunshine

When you own a solar system in Perth, more sunshine means more savings, so it’s useful to know what to expect. Perth receives an annual average of around 5.2 hours of peak sunshine per day. This means that, with a 1.5kW solar PV array operating at about 80% efficiency (typical), a home will generate around 6.2kWh per day on average throughout the year. A 3kW system will produce around 12.5kWh per day, and a 5kW system will produce around 20kWh per day.

Household electricity consumption and PV system generation

Household demand varies by the size of family and the appliances used and how frequently, but as a ‘base case’, the average 3-person home uses 20kWh per day, averaged over the course of a year. This means that with a 5kW solar system, the home’s energy consumption is just about covered by the system’s output provided that the system owners time can time their electricity consumption to match solar PV system power generation.

For residential customers: Currently, residents of Perth and surrounds are offered about 8c/kWh for excess solar power that they export to the grid–far less than the retail electricity rate. This means that the best strategy for Perth residents is to ‘self-consume’ as much of the power that the system generates as possible, while the sun in shining. By doing so, they will avoid incurring charges with their electricity retailer, and save money on their power bills. This, of course, will work best for those who are home during the day, or for businesses that operate during daylight hours.

For educational organisations & not-for-profit customers: Synergy offers generous feed-in tariff rates for not-for-profit, schools, and community organisations. This makes going solar a great investment. Read more: Solar Buybacks for not-for-profits, schools, and community organisations in and around Perth, WA.

Up-front Federal Government Solar Rebates for Perth

Under the federal government’s Renewable Energy Target scheme, households and businesses installing systems up to 100kW are awarded a greater or smaller number of small-scale technology certificates (STCs) depending on their location, the size of the system that they install, and the market price for STCs at the time of installation. These STCs contribute to the up-front cost of installing a solar PV system, ordinarily giving a discount of anywhere from 55-70c per watt for a system in or around Perth, WA.  (Read more about current solar system prices.)

How installing a solar system helps you cut your electricity bill in Perth

Depending on the electricity usage of the household, a solar generator could save Perth residents a significant amount of money on their power bills. It is important to keep in mind, however, that electricity consumption time management is the key to getting the most financial benefit of solar power. Since the Feed-in Tariff is only 7c/kWh, Perth residents get will want to avoid exporting to the grid as much as possible; solar electricity consumed at home is in effect worth as much as the the rates that they pay for electricity from the grid.

How can I find the best deal on solar power in Perth?

Solar Choice, as Australia’s free Solar Energy Brokering and advice service, connects solar PV customers with installers who service their area. We provide comprehensive quote comparisons of solar power installations throughout the country–including in Perth. With a bird’s eye view of the solar power market, Solar Choice is uniquely poised to identify the best deals on offer and facilitate our customers to find the solar system that best suits their needs and budget. Request a Solar Quote Comparison today by filling out the form to the right of this page, or call us on 1300 78 72 73.

Calculate indicative solar power system ROI & payback periods for Perth, WA

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© 2012 Solar Choice Pty Ltd 

(Top image via Wikipedia)

James Martin II

James Martin II

James has been working as analyst and online development manager for Solar Choice since 2011. He holds a master's degree in Environmental Management from UNSW, and a bachelor's degree in Philosophy from Bridgewater State University in his native Massachusetts.
James Martin II

{ 10 comments… read them below or add one }

Ken Stranger June 1, 2012 at 7:19 pm

I am curerntly researching the advantages of Solar in the current scheme of rebates etc and (please correct me if I am wrong) the following statement in the text of your web site I would find hard to believe because you would have to be cosuming all the power during the core sun hours of the day – most households I would expect have highest consumption outside the hours of the solar generated power. So to say a 5Kw system “just about covers the daily consumption” I would suggest is misleading.

Quote” Household demand varies by the size of family and the appliances used and how frequently, but as a ‘base case’, the average 3-person home uses 20kWh per day, averaged over the course of a year. This means that with a 5kW solar system, the home’s energy consumption is just about covered by the system’s output”


admin July 26, 2012 at 8:12 pm

Hi Ken,

Yes, you’re right that that information could be misinterpreted, so I’ve changed the wording. If there is a Feed-in Tariff (which there no longer is in WA), it could be possible to offset your entire bill with a solar PV system. However, in the absence of such a scheme, it is necessary to instead ensure that all the solar power is being consumed as it is being produced–otherwise you are ‘wasting’ the power by letting it go into the grid for 8c/kWh. The system does still, however, afford significant benefit to those looking to reduce their electricity bills.


Tom Slaiter February 6, 2013 at 11:18 pm

Do you have any other calculators? Will the one for Perth work anywhere else?!

Great post, thanks a lot :-)


Solar Choice February 19, 2013 at 11:16 am

Hi Tom,

The Perth calculator will essentially work for the whole of Australia, the Perth specific data is the system price which comes from your Solar Quote Comparison. If you put in all your details you will get a price for systems in your area, you may also need to change the average sunlight hours for your state or area.

We have specific calculators for different states and system sizes which you can check out by searching ‘ROI’ on our website.

Hope this helps


Peter Mansey September 10, 2014 at 1:26 pm

I am researching the installation of solar for my Perth WA home and in this regard I want to make sure that I engage a reputable retailer. Whilst price is important the lowest price quite often does not represent value for money (the non reputable retailers being the culprits). How do I know that your comparator only delivers results of reputable value for money retailers.
Further I note in your advice that the average three person home uses 20kwh per day, is this a 24 hr day or consumption during daylight hours. If it is the former then the figure to me is meaningless noting that solar panels do not produce at night. I would be more interested in the avg consumption figure for daylight hours only. My intention is to have a system that produces enough on average over the course of a year that will offset the kwh I use during the day. In short not looking to make money rather just want to reduce my chargeable consumption.
I have another query. Been reading your Perth WA comments and I note that you state that Perth gets an average of 4 hours of sunshine a day. I assume that you use this figure to determine a system size. I think your figure of 4 hours is incorrect. The Bureau of Meteorology website stats advise that the 94 year average for Perth is 7.9 hours. What impact does this fact have with regard to system requirements.


Solar Choice Staff September 16, 2014 at 5:50 am

Hi Peter,

Thanks for commenting. You bring up some good points.

As for installers in the Solar Choice network: there is a high level amount of due diligence that takes place before bringing any installer on board. In addition to ensuring that all of our installers are accredited through the Clean Energy Council, we also conduct review of the website, product on offer, past installs (quality and volume) and length of time in business are all taken into consideration initially. Pricing, locality and customer reviews/perception are then all looked at before we take an installer on. Each installer’s information is also instantly displayed for our customers as soon as the “Submit” button is pressed on our Solar Quote Comparison request form and we would encourage all of our customers to complete their own research to help make a decision.

About the 20kWh/day household usage figure, you are correct that this is for 24 hours, and only a portion of electricity consumption for a given home takes place when the sun is shining. Actual daytime household consumption will differ depending on the home in question. Our Solar PV Payback Calculator takes this fact into account–you can set your household’s ‘self-consumption’ as a percentage. We encourage all of our customers to make sure they understand what they can expect from a system before they put their signature on a contract–and this means looking at daytime electricity consumption and usage patterns (we’ve written about this topic here.)

Finally, about the 4 hours of sunshine–I’ve actually just updated the article (based on your feedback) to be a bit more accurate. In Perth you can expect 5.2 ‘peak sun hours’ per day, averaged throughout the year. Peak sun hours (PSH) are different from sunshine hours as listed by the BOM–they’re a technical measure used in the solar industry when talking about solar power to indicate hours of ‘peak’ sun. While Perth may indeed get 7.9 hours of sunshine throughout the day on average, the power of this sunshine is not equal throughout the day when looking at it from the vantage point of a fixed solar panel array.

If we’re talking about a north-facing panel array, the sun is weaker in the morning, strongest in the afternoon, and then weaker again as the sun is going down. When you compress these various degrees of sun strength into uniform units (PSH), you come out with about 5.2PSH for Perth. If you have 1 kilowatt (kW) of perfectly efficient solar panels, and you shine 5.2PSH on them, you will get (1kW x 5.2PSH =) 5.2kWh of solar electricity.

The 4 sunshine hour figure was not technically correct–it should not have been sunshine hours of input, but rather kWh of output. To explain further: A solar PV system is never perfectly efficient; it is realistic to expect about 80% efficiency from a typical solar array. If the total nameplate capacity of your array is 1kW, and you live in Perth (where you can expect 5.2PSH per day on average), then in a ‘100% efficient’ scenario, your system will produce (1kW x 5.2PSH =) 1kWh of electricity. Once we apply the 80% to this figure, we get down to about 4.16kWh, which is a more realistic expectation for a well-designed and optimally installed system. This is where the original 4kWh figure came from. Applying this 80% efficiency derating to a 5kW solar system, we would get (5kW x 5.2PSH x 80% =) 20.8kWh.

Hope this helps! Feel free to get in touch if you have any more questions.


John December 13, 2014 at 11:40 am


I am enjoying reading your website and only wish I had made some better decisions based on your information.
I built a new home in the south west of Wa in 2012/13, during construction I invited 2 solar pv companies to price a 5kw system for our new home. Both were negative and we did not proceed believing it was a hopeless case. The house is 2 storey, skillion roof with10 degree pitch which faces due west.
After attending a sustainability seminar last week in Perth I get totally different advice that I will lose approx 15% efficiency only!! And it’s still well worth doing. We just want to decrease our synergy bill more than anything, we have roof and wall insulation, solar heat pum hot water service, ceiling fans, full led lighting and excellent cross ventilation design with louvred. I find that heating is more the issue than cooling as we do not have access to mains gas we have reverse cycle aircon.
Is a battery system worth investing in ( more due to cost and lifecycle of batteries)
Thanks for your time


Solar Choice Staff December 16, 2014 at 1:09 pm

Hi John,

Thanks for your comments. We’ve definitely noted before that west-facing roofs are a good options for homes that don’t have an unobstructed northerly aspect.

As far as energy storage is concerned: systems are steadily becoming more affordable and more and more homes are seriously considering them, but we are currently advising folks to wait until they find a deal that makes financial sense. A solar PV system without energy storage, if sized appropriately (i.e. to meet the household’s electricity needs) should have a payback period of under 7 years in most parts of Australia–4 or 5 is not unheard of. We’d only recommend going with energy storage if you can find a system that is comparable to that.


Ann Boyer January 13, 2016 at 4:55 pm

Microinverters versus say a Frontius regular inverter – how reliable with heat problems? Perth Temperatures get very high in summer. I understand the advantages but . . .


Solar Choice Staff January 20, 2016 at 3:21 pm

Hi Ann,

I’ve reached out to both Fronius and Enphase (the world’s biggest microinverter manufacturer) to get a response to your question. Below are the comments they sent to me:

From Fronius:

All decent inverters have temperature sensors, which are designed to protect the inverter from heat related failures. They also have been tested to hot Australian conditions (like Fronius inverters have).

The main problem for microinverters is that they are mounted on the roof with only the shade of a solar panel to protect them. Australian tin rooftops can easily get to 60 – 70 degC on a hot summer’s day. If you check out the datasheets of most microinverters, they will start derating their power output at 65 degC and will totally shutdown at about 85 degC. Fronius string inverters, for example, are mounted in much cooler locations out of direct sunlight (say on the south wall of your house) in an ambient temperature environment so they have a much easier life. When power electronics are involved, it’s best to keep out of the heat!

Also, as we always mention, reliability is not just about the product not failing but how you get the system back up and running. See white paper attached from our colleagues in the US.

Micro inverters even if reasonably reliable under heat conditions have a problem when it comes to service and maintenance vs Fronius inverters due to their scaling limitations.

(You can download the Fronius Whitepaper here.)

Enphase referred me to a paper from their ‘Mythbuster’ series (which you can download here). Below is an excerpt from this paper. If you’d like more details, please see the document itself.

During the summer of 2014, extreme heat took a heavy toll on Australia, sparking bushfires and melting tar in the roadways. For three scorching weeks, Enphase closely monitored over 2,000 microinverters. None of them shut down because of the heat.

Enphase Microinverters cope with these conditions for two reasons. Our engineers have designed them to maintain a low thermal footprint, and our installers have kept them away from direct sunlight and heat from the roof.

When Australia needed renewable energy the most, Enphase Microinverters delivered.


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