A bunch of rooftop solar power systems in South Australia could go offline for a while today. But don’t panic – the collapse event (if it occurs) will be a feature, not a bug.
Commercial use and solar home in south australia has been phenomenal, with more than 355,000 photovoltaic systems installed statewide to date. The impact of all this solar power goodness was very apparent at the weekend, when on Sunday afternoon at 1 p.m., rooftop solar alone met 92% of the electricity needs of the house. ‘South Australia.
Events like this will become more frequent, especially in the spring, when mild temperatures and clear skies combine with reduced demand for heating and cooling homes and buildings.
But sometimes you can have too much of a good thing. Too much generation or too little demand from the grid can lead to power system instability – and that’s a very bad thing. This is why it has been mandatory since September 28, 2020 that all new solar installations in South Australia can be disconnected (and reconnected) remotely if the need arises, which means that most of these households s will supply electricity from the electricity grid during this period. an event.
The introduction of remote solar disconnection – to be used as a measure of last resort – has created angst and misinformation, which SolarQuotes founder Finn addressed in his explanation of remote solar stops here.
“High risk” of disconnection from the solar system today
As far as I can tell, the ability has barely been used since it was introduced. But that brings us to today where it can be brought into play.
The situation was reported last night by Paul McArdle of WattClarity after Australia’s Energy Market Operator (AEMO) issued a notice around 8.30pm warning of the potential.
Contract notice 102367 indicates that there is a high risk of “contingent disconnection of the distributed PV (DPV)” from 10:30 this morning until 2 this afternoon. The notice states:
“The Australian Solar Energy Forecasting System 2 (ASEFS2) predicted maximum DPV generation is 1307 MW at 12:30 p.m. and the safe ASEFS2 generation limit for the forecast operating conditions is 1181 MW.”
.. and this could mean among the actions:
“…an instruction to keep DPV generation below a safe DPV generation threshold.”
This would mean remotely disconnecting a bunch of rooftop solar systems from the grid, which will be remotely reconnected once the situation subsides.
What’s happening is not a done deal – latest weather report says ‘mostly sunny’ conditions; so there may be a bit of cloud around or other factors obviating the need to do so. And if a remote disconnect occurs, it shouldn’t last long – not necessarily the full 10:30-14:00 period.
As mentioned, the remote disconnect potential only applies to new systems installed since September 28, 2020. Even if a solar shutdown instruction is issued, not all systems may be disconnected from a distance.
As far as I can tell, solar plant owners who have installed systems since this requirement was introduced to be the least affected would be those who have household batteries with “level 3” backup capabilities. Their solar energy systems must disconnect from the grid but continue to power the house and charge the battery.
As the owner of one of the potentially affected systems (and having no battery), I will be keeping a close eye on my solar system monitoring today between 10:30 a.m. and 2:00 p.m. I’ll update this post if I spot anything unusual, or with AEMO updates on the situation.
UPDATE 8:10 am: AEMO last notice still indicates potential for a remote disconnect today.
UPDATE 10:45 a.m.: At this point everything seems to be fine – but I noticed on OpenNEM that wind generation in South Africa has dropped dramatically over the past two hours. Whether wind power is reduced or simply abandoned due to conditions is unclear.
UPDATE 11:18: AEMO canceled Distributed PV Contingency 2 (DPVC2) [and Distributed PV Contingency 1 (DPVC1)] in SA. Everywhere, red rover.