The state of South Australia has one of the fastest adoption of renewables – wind and solar – after Queensland and NSW. The consistency of these renewable systems have also been in question in the past during power outages and the 2016 blackouts. This Tuesday, the south Australia electricity prices were negative for a total period of 6 hours.
A moderate autumn-day demand, high output from renewable energy systems and the 50MW export limits on the state (by AEMO) resulted in the negative wholesale electricity prices. This continued throughout Tuesday, and for multiple half-hour intervals on Wednesday. The grid demand was completely covered by the SA wind farms and rooftop solar systems.
On tuesday, at 10 am local time, the negative pricing began. The lowest point was -$120/MWh. The wholesale electricity prices on Wednesday reached the lowest limit of -$92/MWh and stayed below zero for another three hours. Furthermore, the 50MW export limit of AEMO will continue throughout the week.
South Australia has a very ambitious renewable energy target (RET) of 100% by 2026. As of 2018, the state has an accelerated surge in solar battery uptake and policy amendments to boost their adoption.