There are times of the day when rooftop PV solar is generating more power than is being used. The utilities had to pay users to use it and the prices went into the negative. They have to remotely turn off some solar.
What I see is that they should build several pumped hydro storage systems to supply power when solar cannot, and thus use up some of the excess power. Another thing they should do is build is hydrogen electrolyzers and store the hydrogen underground.
https://www.pv-magazine-australia.com/2022/05/14/weekend-read-australias-looming-solar-cliff/