The extent to which your rooftop off grid solar system may be scaled back depends on several variables, including the capacity or strength of your local power network and whether your neighbors also have rooftop solar panels.

Dr Yildiz said: "If every house has solar power, then it is likely that every house has downsizing.

He added that rural areas tend to have weaker networks, which makes them more prone to downsizing.

"If you're in a rural area with a lot of solar, then you're likely to be curtailed."

More than a third of independent home owners in Australia have solar panels on their roofs, with close to 40 per cent in Queensland, South Australia and Western Australia, and more than 50 per cent in some suburbs.

In the Perth suburb of Baldivis, for example, more than 69 per cent of homes have solar.

To check if your power generation system is being scaled back, you need a smart inverter that sends energy output data to a monitoring application.

Or just check your electricity bill to see if there are any major discrepancies.

What happens to the reduced power?

It has nowhere to go because it doesn't exist.

This is because in order to produce electricity, solar panels require a potential difference provided by the grid or the household devices that consume electricity.

If we use the analogy of a tank with a hole in the bottom, the potential difference (another word is voltage) is the pressure acting on the water that rushes out of the bottom.

When the inverter disconnects the solar panel, the outlet is closed, so there is no potential difference.

So you don't have to worry about out-of-use panels electrifying your roof.

"I think people are pretty frustrated."

For some rooftop solar owners, the downsizing boils down to a slightly lower return on their investment.

But because tapering is difficult to measure at the household level, few families are aware it's happening, says Sophie Adams, co-author of the UNSW study.

"The issue has been surprisingly low priority for networks and retailers, who don't know who is actually affected in the network," said Dr. Adams, whose work studies the social impact of the transition to renewable energy.

For the study, researchers conducted interviews with South Australian households that had solar power.

"I think, in general, people are quite upset when they find out that they're doing [tapering]," she said.

"They chose to put a solar system on their roof, and most seemed to feel they were doing it for several reasons, including financial ones, but also thought they were doing the right thing for the environment.

"It's a little disappointing that they didn't know it was a problem. No one told them. It feels a bit like punishment."

It's not the fault of networks or retailers, she added.

"They couldn't have been warned that this was going to happen because it was a new problem. Ten years ago, no one could have imagined that we would see this."