Understanding Solar in South Australia

Solar in general is one of those things that the more you look into it, the more confusing it gets. Realistically more information is good problem to have, however it can make looking into solar a chore that many just see as too hard and throw in the towel. As if it wasn’t hard enough to navigate already, you also have the local rules for solar in each state of Australia. To make this easy for our neighbours here in South Australia, let’s run through some of the local SA solar rules to help you understand what solar might look like for you.

Why do I keep seeing 6.6kw advertised everywhere?

This question seems to come up the most and is relevant to anyone with a single-phase supply to their property. The SA Power Networks requirements dictate that on any single-phase property the maximum size inverter you can have before you need to export limit is 5kW. You are however, allowed to overload the inverter size with panels by approximately 33%, and that’s what gives you your 6.6kw. By increasing the number of panels to 33% over the size of the inverter, this helps drive the system to work more efficiently in the colder months and helps to start the solar running earlier in the day and stay on longer in the afternoon, producing more energy through the year as a result.

With all this being said, just because you have single-phase at your property it doesn’t mean you can’t go bigger with your solar, technically speaking with a single-phase property the maximum you can go to is a 10kW inverter with 13.3kW of panels on your roof. Any inverter capacity over 5kW (up to a maximum of 10kW) will need to be export limited to 5kW maximum. So, what does this mean? Export limiting allows you to put a bigger system on your property but will limit what can be exported back to the grid to 5kw. For example, if you wanted to put a 13.33kw system on your property, you would use a 10kW inverter (keeping in mind the 33% increase rule). With export limiting, what will happen is that inverter will be allowed to produce a maximum of 5kW of power for exporting back to the grid and only produce more than 5kW if there is energy demand in the house. For example, if you are consuming 3kw of power in the home at any time then that 10kW inverter will produce a total of 8kW of power; 3kW into the house and 5kW exporting to the grid. If you are using even more in the home, then the inverter will produce more (up to 10kW maximum at any one time). This example of course is assuming that they weather is optimal.

So, what’s the point?

Well, there are several reasons you would get a system that is export limited, particularly if you are a high energy user during the day, or you have a pool (among other things) working during the daytime hours. Regardless, it is still going to save you more money as it will work much more efficiently, and we all have fridges etc running during the day even if we are at work, right? It’s just a case of how big you go before you are wasting too much energy and even money on an oversized system. 13kW is often too big for most, they might opt for around 8kW. You’ll find that export limited systems work exceptionally for those who have high usage throughout the day, but if you do opt for a bigger export limited system and not much is happening at the house during the day, become familiar with timers on appliances like dishwashers and washing machines so you can have them run during the day whilst the solar is working at its best.

Another way to make the most of an oversized solar system is to install a battery. As a battery will demand power to charge, the solar can work beyond the export limit of 5kW and feed the battery power to charge it, and still export 5kW back to the grid if it’s working at its maximum. This increases the savings even further by exporting the most you can for credits and filling up the battery for use in the home at night, decreasing your dependence on the electricity grid even more.


The government can now control our solar, is that true?

Well technically I suppose you could say yes but it’s not what you think. With all new systems from late September 2020, the SA Government introduced a rule where if there were issues with the power grid in a particular area, solar inverters in that area can be shut off to prevent too much excess solar being fed back into the grid and in turn help restabilise it. The problem is South Australians were so good at taking up solar power that our infrastructure got to a point where it could no longer cope with the influx of solar feeding in. It got to a critical point where if nothing was done, we’d start seeing blackouts on a regular basis and for obvious reasons this just can’t happen. So, upgrade the grid, right? Well in theory yes this sounds like the way to do it, but unfortunately this task is predicted to take a very long time and an infinite amount of money so it’s just not an option. The thing you can have confidence in is the inverter shut offs happen very rarely. This means as far as savings go, this will barely affect you at all and is a far better option than having consistent blackouts.

I’ve heard something about flexible exporting, what is that all about?

Flexible exporting is a new rule that came in late this year which is currently still under trial. Currently only certain parts of Hallett Cove, Sheidow Park, Trott Park, Reynella, Old Reynella, Reynella East, O’Halloran Hill, and Happy Valley are affected but if successful (which no doubt it will be) it is set to be implemented for all new solar customers come late 2022. In a bid to lighten the load on the grid further, the new rules are basically being put in place to reduce how much solar is being pushed back into the grid. You are given a choice of either limiting your export to a fixed 1.5kw, or alternatively you can opt for flexible exporting which allows you to export from 0-10kw back to the grid at any given time but is determined by how busy the grid is. Once this rule comes in for everyone it will affect what you save with solar but that won’t be in until late 2022. I suppose the general message is to get your solar sorted before this new rule comes in to play but also don’t be discouraged if you are now affected by these rules, solar will still save you a tonne of money.

There are other rules that are very scenario specific which may need to be discussed with you upon designing a solar plan for your home, however this should give you a good grasp of the main rules surrounding solar here in SA. Considering how much needs to be considered when purchasing solar and batteries, it’s best to arrange a meeting with one of our consultants to ensure you get the right system for your needs.  Call us now on 8451 2120.