Are Flexible Solar Exports Worth It? Trevor’s Testing

Owners of solar power systems in many more locations across South Australia recently became eligible for flexible exports. SolarQuotes’ Trevor took the plunge – and here’s what happened.

Hundreds of thousands of solar systems have been installed in SA, creating some management challenges for the state’s Distributed Network Service Provider (DNSP), SA Power Networks (SAPN).

Where uptake of solar panels is particularly high or the local electricity network not so robust, this can lead to network stability issues and other problems during periods of low electricity demand and elevated levels of surplus solar energy going into the grid. SAPN’s tool of last resort is remote disconnect/reconnect; but a more elegant approach is flexible (aka dynamic) exports.

In 2017, SAPN set an export limit of 5kW as standard. But new flexible exports allow for a much higher limit depending on network conditions on any particular day – up to 10 kW per phase. When there’s too much solar in the grid, exports will be automatically adjusted down so the network doesn’t overload, then adjusted back up when the situation passes. Signals setting the limit for whatever period are sent remotely to a system’s inverter (or compatible device), and all solar systems installed in South Australia since July 2023 have been required to be compatible with this functionality.

Flexible Exports Rollout Timeline

After a trial in 37 Adelaide suburbs experiencing congestion issues, SAPN started offering flexible exports more broadly through a staged rollout. This was initially 120 suburbs in July 2023, followed by another 200 locations last week – and with more to come. SAPN’s goal is to have flexible exports available across the state by the end of 2024 as a standard offering.

For New/Upgrading System Owners

In suburbs and towns where flexible exports are available, owners of new systems or existing systems being upgraded have a choice of either a reduced permanent fixed export limit of 1.5kW per phase or the flexible option (1.5kW – 10kW per phase). Your installer will submit the application on your behalf after a discussion with you about the options.

For Owners Of Existing Systems

Owners of existing solar systems can choose to do nothing and stay on what was previously the standard 5kW export limit – or make the switch to flexible exports via their installer; assuming the system is compatible and in an eligible area.

IMPORTANT: SAPN informed me if the owner of an existing system chooses to move onto flexible exports, they cannot revert to the 5kW standard limit at a later date. So, choose wisely.

To get a rough idea of the impact, you can check your address or National Meter Identifier (NMI) number against SAPN’s eligibility checker. This will provide an estimate based on your area’s performance over the last 12 months. In my case it shows I can expect to export at the full 10kW capacity 98% – 100% of the time if I had a system capable of doing so.

The 98% doesn’t mean that 2% of the time I may be exporting just 1.5kW. It means that 2% of the time it might not be the full 10kW, but it could be 8kW, or 9kW – or less of course.

SQ’s Trevor Takes The Flexible Exports Plunge

SolarQuotes’ General Manager Trevor wasted no time in making the switch. Trevor’s system specs:

• 42 x Jinko Solar panels: JKM475N-60HL4-V (total 19.95kW capacity)
• Sungrow inverter: SH10RS (10kW capacity)
• Sungrow battery: SBR128 (12.8kWh capacity)

It’s a big system¹ as Trevor has two electric cars to charge from it – a BYD Atto 3 and a BYD Dolphin.

After receiving notification flexible exports were available in his suburb (he was on an SAPN notification list), Trevor’s first step was to get his installer, Deionno Electrical, to complete the necessary application for SAPN on his behalf. The good folks from Deionno then updated his inverter’s settings and awaited SAPN to complete testing.

The process was smooth and rapid. From the time Trevor contacted Deionno Electrical to when he received approval notification from SAPN was around 24 hours. And here’s how things looked during the first full day of flexible exports, compared to when he was on the 5kW limit.

Trevor said on this day, the 1.5 kW minimum lasted less than an hour and then it was pretty much 100% after that. As he has a 10 kW inverter, he’s not going to export much more than 9 kW at any given time.

The big test will be during mild and sunny days during spring when grid demand is low and solar exports are high. No doubt we’ll do a follow-up article in a few months’ time to see how Trevor’s travelling and to crunch some numbers.

Where South Australia has gone, other states will follow, so it’s worth keeping your finger on the pulse of what’s happening. Learn more about SAPN solar flexible exports here and sign up for the SolarQuotes newsletter here.