6.66 kW Solar pricing and savings in 2022

If you’ve ever searched installing solar panels in Adelaide or anywhere in Australia, then you’ve probably come across the 6.6 kW system. Why is it so big? Why do installers tend to push this system over any other? To understand why it’s the most recommended residential solar PV system in Australia, we’ll have to look at some of the backgrounds.

Why 6.6 kW Specifically?

The 6.6 kW is about the total number of solar panels in the system that cumulatively add up to 6.6 kilowatts of power. Individual solar panels are usually anywhere between 300 watts to 400 watts. So if we take a standard 330-watt solar panel, we’ll need 20 to get a 6.6 kW system. Now that sounds like many solar panels on your roof, and it is. But luckily, there are higher-rated solar panels that’ll reduce the number, which will also result in a smaller footprint on your roof.

But you’re probably wondering, why 6.6 kW precisely? Why not round down to 6 kW or up to 7 kW? The reason behind this is the 5 kW inverter and the regulations that surround it. Australia, the maximum allowed inverter for a residential solar PV system is 5 kW. On top of that, the total solar power output must be no more than 33% of the 5 kW inverter. With simple math, that equates to 6.6 kW, and thus this system is what almost every installer would recommend. There are many reasons for these limitations, but we don’t need to go into the nitty-gritty technicalities.

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    Remember that you don’t have to precisely restrict yourself to a 6.6 kW system, especially if you have limitations on roofing space or budget.6.6 kW is simply the maximum amount you can install on a single-phase unless you allow export limiting; then, you can go up to 10 kW. For example, Q Cells provides quality 350-watt solar panels, and just 18 of these panels will result in a 6.3 kW system that’s still under the regulation of 33% and a cost-effective option. Not to mention, it’ll not take up as much space as a 20 solar panel system.

    What is A 6.6 kW System Good for?

    The estimated power output of a 6.6 kW system is around 22-24 kWh a day. To put that into perspective, that’s enough to supply a household of four with extra energy for storage or to export back into the grid for the feed-in tariff. Of course, many factors can affect the actual power output of your solar PV system.

    In Adelaide, there are instances where a 6.6 kW system has been known to provide upwards of 36 kWh in one day, which is more than enough to power a household of six. At least during the summertime, the winter months will drastically drop the system’s power output no matter what size it is.

    Now you may be asking why use 6.6 kW solar panels if the inverter is only 5 kW anyway? The fact is that solar PV systems will rarely reach the maximum rated output. So going above the 5 kW inverter limit is simply a good design. 

    Benefits of a 6.6 kW System

    The main benefit of a 6.6 kW solar PV system is its efficiency in helping you lower your overall power bill. You’ll even have the potential of earning credits for exporting excess power produced back to the grid, resulting in even more savings.

    First, let’s talk about the feed-in tariff. Many variables affect your feed-in tariff, including where you are and your electricity retailer. As of January 2022, rates in Adelaide range from 7x per kWh to 12c. Some premium feed-in tariffs are known to be as high as 44c per kWh, but those were primarily early solar adopters. You can ask your installer or electricity retailer for pertinent information to get specific details.

    Just to give you an idea, let’s take an average household of four in Adelaide with a brand new 6.6 kW solar PV system. Including the federal rebates, it had cost the family $4,500 to install, and they are consuming about 22% of the power produced. In their first year of solar energy, the family would have saved about $1,600 on their power bill. They would have recuperated the initial investment with that rate in just under three years. And since solar PV systems are designed to last over two decades, they’d have earned over $31,000 in savings by that time.

    How many solar panels are needed for a 6.6 kW system?

    Solar panels come in a range of sizes and power ratings. But typically, it’ll take about 20-24 solar panels to hit the 6.6 kW sweet spot. The average size of a single solar panel is about 1.6 square meters.

    What is the power output of a 6.6 kW system?

    On average, a 6.6 kW system can produce about 20 kWh to 27 kWh a day. This would also depend on many factors such as location, the orientation of the solar panels, and the weather. But it’s generally accepted that in southern areas such as Adelaide, you’ll probably get upwards of 27 kWh on a good day, whereas in Melbourne, it lowers at an average of 23 kWh.

    How much does a 6.6 kW system cost?

    For a good quality solar PV system installed by a respectable company, you can pay anywhere between $5,000 to $8,000. That may seem quite steep at first, but considering the average household electricity consumption, you’ll recuperate your initial investment in just 3 years – give or take. So it’s like it almost pays for itself.

    What are my potential savings with a 6.6 kW system?

    Considering a household of four in Adelaide, you could be seeing savings of about $1,600 per year. But the good news is that you can quickly recuperate your initial investment in just three years or so, depending on your electrical consumption and feed-in tariff rates.

    About Us

    Natural Technology Systems are solar providers that have been in business for over 30 years; we are a business that South Australia trusts and provides expert, obligation-free quotes and advice. We provide customers with the most cost-effective way to slash those power bills for your home or business.

    Click here for a quick quote for your solar power needs, or contact us today at (08) 8344 7298. You can also email us for expert, obligation-free advice

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