Around 100,000 rooftop solar systems in South Australia will be switched off for an up to an hour on Tuesday as the local distribution network operator tests its so-called backstop system to help protect the grid.
SA Power Networks describes the one-a-year exercise as “like a fire drill for the grid”, and the number of times it is tested has so far outnumbered the times when it has been called into action.
South Australia leads the country, and the world, in the uptake of wind and solar, and rooftop PV in particular, and the output from rooftop solar systems on homes and businesses often exceeds state demand, and pushes the local grid into “negative” demand.
The problems that this can create have been mitigated in the last 12-18 months by the rapid uptake of home batteries, courtesy of the federal battery rebate, the increase in the amount of grid-scale batteries – which can both soak up excess solar – and the growth in electric vehicle and electric appliances, which creates new demand.
Networks such as SAPN have also been exploring more subtle program such as flexible exports and more recently flexible imports, and create tariffs that reward households to respond to any tricky situations.
