what if instead of worrying about the storage. connect the collectors and you give the amount thats not needed into (mega complex not yet developed, maybe ppl thought about it b4 ofc..) system and its distributed to the person who needs it + you get something like bitcoin for the shared power, and if you need some you can buy it with those coins then....
There have been thoughts about using the batteries of E-Cars to store it. Since it is highly likely that the amount of E-Cars will increase in the future, and because they have a huge battery to store the required energy, this might be a good way not only use the energy yourself, but also store it in order for it to be used when needed.