For a lot of places in the world you would need more storage than you need production units, especially further away you get from the equator and deserts. Fixing enough production from wind and solar is already well economical up to a point of 100% capacity with some countries already there, but with around 50% of actually energy consumption being from renewable.
We don't even need to litter the ground as ocean based wind farms are quite effective in using the wast amount of oceans we have. If however we are going to stop using fossil fuels we need to convert that energy into a storage medium like hydrogen, having massive pipelines to transport it, have large amount of storage facilities, and built equal amount of capacity of gas burning power plants as we have renewable capacity demands. The economics of that is the tricky bit.