How can your solar panels be remotely turned off?

In last month’s clean energy article, I explored the impact a nuclear energy industry would have on homeowners’ rooftop solar. This month I follow on with an explanation of exactly what the mechanism would be that would allow this to happen. 

Let me begin by saying the answer depends on what state you live in, but then concentrate on Victoria. There are 2 ways that your ability to export to the grid could be curtailed.

The first is that the Australian Energy Market Operator (AEMO) could instruct the distributors (eg Jemena, Powercorp etc) to raise the voltage which could trip your inverter and turn off your export to the grid. However, this method is crude and no one wants to do this except in absolutely exceptional circumstances.

The second is for AEMO to instruct distributors to remotely control rooftop inverters. The inverter is an essential component of any solar system. Inverters have a wifi connection so you can get a readout of what your solar panels are producing, and this allows a signal to be sent over the internet. In most states, systems that have been installed in the last few years must come with the capability to be switched off remotely and in the future it’s likely only those with this capacity will be permitted.

What if my wifi is down?

If your wifi is down – maybe you’ve turned it off because you are away from home or for another reason, or your router is offline – then your inverter can’t be switched off. This will probably happen in about 20% of cases.

When my inverter is switched off can I use energy for my home?

The preferred approach is only to turn off your export to the grid but this again depends on the sophistication of your inverter.  Some older models may not have the intelligence to turn off export to the grid and retain the capacity to balance your household usage with your solar panel output, and in this case your panels would stop generating and all the electricity you use would come from the grid.

Can inverters be upgraded?

Yes they can. If there was a requirement to upgrade, the question would be, ‘Who would pay?’

When would curtailment happen?

Curtailment is most likely to occur in the shoulder seasons i.e. spring and autumn. In the summer, demand for solar is high particularly when we need to turn on cooling devices such as fans and air-conditioning, and in winter when we need to heat our homes, there isn’t excess in the system. In the shoulder season, when days are mild and demand low, we can get too much rooftop solar but this is not the fault of rooftop solar, but rather the inflexibility of the energy system as a whole. 

What is meant by inflexible supply system? 

While rooftop supplies overall about 15% of our energy, on mild sunny days its peak midday output can meet as much as 55% of all demand – and increasing as more households install solar. At such times only 45% is left for coal-fired, large-scale solar and large-scale wind generation. Large-scale solar and wind can be scaled down to zero if necessary but not coal. Coal hits a floor at 40-50% of its capacity (maximum output) as coal-fired generators can’t be shut off for brief periods. With nuclear, the position is worse. If coal was replaced with nuclear, which can only reduce to about 70% capacity, the inflexibility problem would greatly increase to the detriment of rooftop solar, which would be curtailed more often.  

Written by Robin Gale-Baker 

I am indebted to Allan O’Neil, independent energy market consultant, for the information in this article. Any errors are mine alone. Here’s a link to an interview that is more detailed which I conducted with Allan for the Village Power newsletter.

https://www.villagepower.com.au/news/2025/what-would-nuclear-energy-mean-for-your-solar-panels-xjah6