What Size Solar System Should You Get?

Posted 2 Nov '17
What Size Solar System Should You Get?

What Size Solar System Should You Get?

If you are thinking of putting up a rooftop solar, you are probably wondering how much capacity can you achieve. You also need to know if there any restrictions. Fear not because we are here to explain everything. When it comes to sizing, up to 5kW is standard for many households in Australia. This is because it is something many can afford and it usually covers all the basic needs.

A system this size will provide enough energy, and even a surplus you can use for charging the battery bank. If, however, you are not ready to invest in a battery storage, the surplus has other uses. It will earn you some solar feed-in credits on your monthly electricity bill. It’s recommended to go smaller than this only if you have an unshaded part of the roof or not enough money. Furthermore, if you know that your household energy consumption is low, then a smaller system might be a better choice.

However, even though this is the most popular size right now, it doesn’t mean you can’t go bigger. If you have a higher demand and a budget to cover it, then a large-scale system isn’t going to be a bad choice. When talking about network companies, however, bear in mind that they provide services to you. Your home is connected to the power grid and they own and control the poles and wires. Still, in some regions, these companies might be the same ones that sell you the electricity. Usually, they are separate entities. So, why are there limits on system sizes? It all comes down to the electricity infrastructure. It should work without a specific direction. That means that the electricity generates at centralized generators. Therefore, it was not intended to change courses and it might never will, unless technology allows it in the future.

Generally speaking, and according to the new AS/NSZ 4777 standard, the limits are:

  • For a single phase connection – up to 5kW
  • For a three-phase connection – up to 30kW 

However, there is a procedure which determines what kind and what size of a system you can get. It should meet certain requirements, and those can vary from network to network. Still, the size limits may not be that rigid. It is possible to allow a larger system for a certain household. But, bear in mind that that might lead to extra fees and longer waiting for the installation.

Also, the solar feed-in tariff may not be applicable if you get a bigger system because the system may not get the energy exporting approval. This would mean that your household would have to do everything in their power to self-consume the solar energy they produce. Otherwise it would be going to waste. Nevertheless, you should always inform yourself because these rules can vary from network to network, area to area.

Remember to ask the important questions:

  • Does the limit apply only to solar inverter capacity, or also battery inverter capacity? Usually, the solar system automatically exports the excess energy into the grid. However, battery systems with inverters might not be able to do so. Because of that, certain networks do not include the battery inverter capacity into the maximum size limit. 
  • Do you need export limiting/export control and solar smoothing devices? Some networks have problems with solar going into the grid. That’s why they require you to get an export limiting or controlling device. Furthermore, some also require a solar smoothing device. This is a battery bank that manages and prevents sudden variations which can create chaos due to passing clouds.
  • How certain is a size limit? If you meet certain norms, maybe they will allow you to install a larger system. However, this might require export limiting or even fees for changing the physical network infrastructure in your region.

So if you are ready to make the switch to solar, give us a call on 1300446374 for a free quote or check out for more information.

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