South Australia's renewable energy boom has achieved a global milestone.
Photo: 123RF
The state once known for not having enough power has become the first major jurisdiction in the world to be powered entirely by solar energy.
For just over an hour on Sunday, 11 October, 100 percent of energy demand was provided by solar panels alone.
"This is truly a phenomenon in the global energy landscape," Australian Energy Market Operator (AEMO) chief executive Audrey Zibelman said.
"Never before has a jurisdiction the size of South Australia been completely run by solar power, with consumers' rooftop solar systems contributing 77 percent."
Large-scale solar farms, like the ones operating at Tailem Bend and Port Augusta, provided the other 23 percent.
Any excess power generated by gas and wind farms on that day was stored in batteries or exported to Victoria via the interconnector.
Too much of a good thing?
Analysts say it is a significant milestone that will happen more regularly as the pace of solar growth continues.
Energy regulators say without careful management, grid stability could be at risk if there is more electricity going in than coming out.
If the interconnector is down, like it was for more than two weeks in February, that is when problems can occur.
AEMO is forecasting an additional 36,000 new solar rooftop systems will be installed in South Australia in the next 14 months.
That is on top of the 288,000 homes - about a third - already generating their own electricity.
Household uptake continues
Jackie Thomson has just had 20 panels fitted to the roof of her Adelaide home.
"I'd been thinking about it for a long time and my electricity bills were going through the roof," she said.
"I just decided the time was right … I couldn't spend my money going overseas so thought it was a good time."
She was not put off by new powers introduced last month allowing the electricity distributor SA Power Networks to switch off all new solar installations if too much solar was putting the system under pressure.
"I understood that it was actually about managing the grid more effectively and I wasn't concerned about it, so it didn't impact my timeline for making a decision," she said.
Solar retailers say most people have not been put off by the changes.
"It didn't stop the flow of enquiries, it was just more interesting conversations we had to have to educate people on those new regulations," Adam Karroum from Adam Solar said.
The changes were introduced because AEMO was worried all that extra rooftop solar could play havoc with voltage levels and end up causing blackouts.
New inverters must have software that allows them to be controlled remotely.
Switch-off power needed
AEMO suggests similar action is "required urgently in Victoria, and promptly in Queensland".
SA Power Networks says any switch-off would only happen as a last resort and if grid stability was at risk.
"The system needs management," company spokesman Paul Roberts said.
"In 2009, we probably didn't have any solar panels connected to the grid; now we have a third of customers with solar on their roofs and this is going to become more of an issue as we go forward."
He says solar is still a great investment and the network is working hard to double solar capacity within five years.
"It's an exciting future for South Australia and we have a whole number of things that we are putting in place to manage that," he said.
That includes making it cheaper for people to use power during the day and encouraging people to switch on dishwashers, pool pumps and hot water systems in the middle of the day.
The next step is convincing more people to connect batteries to store cheap energy during the day.
"The grid needs to become increasingly like a set of lungs," AEMO chief external affairs officer Tony Chappel said.
"During the day, the lungs would breathe in and excess energy can be stored and then in the evening when the sun's gone down, that energy can be fed back."
Plans to build a new interconnector with New South Wales will also help manage the growth of solar.
"South Australia could become a net exporter of energy," Roberts said.
"People are going to be looking at the opportunities that a new interconnector may create for solar farms to export to the NSW market as well as the Victorian market."
- ABC