That technology is cables. Cables allow us to move energy over long distances. And with HVCD cables that can mean across continents, oceans, time zones, and climate regions. The nice things about cables is that they are currently being underutilized. They are designed to have enough capacity so that the grid continues to function at peak demand. Off peak, there is a lot of under utilized cable capacity. An obvious use for that would be transporting power to wherever batteries need to be re-charged from wherever there is excess solar/wind power. And cables can work both ways. So import when there's a shortage, export when there's a surplus.
And that includes the rapidly growing stock of batteries that are just sitting there with an average charge state close to more or less fully charged most of the time. We're talking terawatt hours of power. All you need to get at that is cables.
Long distance cables will start moving non trivial amounts of renewable power around as we start executing on plans to e.g. connect Moroccan solar with the UK, Australian solar with Singapore, east coast US to Europe, etc. There are lots of cable projects stuck in planning pipelines around the world. Cables can compensate for some of the localized variations in energy productions caused by seasonal effects, weather, or day/night cycles.
For the rest, we have nuclear, geothermal, hydro, and a rapidly growing stock of obsolete gas plants that we might still turn on on a rainy day. I think anyone still investing in gas plants will need a reality check: mothballed gas plant aren't going to be very profitable. But we'll keep some around for decades to come anyway.