This sounds awesome and it’s great that Solar is so cheap. But if it’s only available several hours in the day at best is it really that practical? Or am I just misinformed and we have grid scale storage already?
A dollar spent on renewables is still better spent on generating capacity, most places, even if peak power is given away part of every day.
Storage cost is falling even faster than solar ever did, so waiting until next year gets you more storage for the price. Also, transmission to local storage is low-loss, so you don't strictly need to be responsible for both. Finally, demand for peak generation will only increase as synthesis (H2, NH3, etc.) capacity comes online. Stockpiled H2 and NH3 will prove entirely adequate as bulk storage despite their low round-trip efficiency, given just a few hours of a better alternative, and anyway that efficiency will only ever improve.
The main attraction of H2 and NH3 storage, despite current lossiness, is that the equipment can operate even after the tanks are full, because there will be unlimited demand for both, for a long time. That is, anytime you are not actually drawing down stored energy, the expensive synthesis equipment can be producing to sell, producing revenue. Similarly for liquified air (N2, really).
Your intuition is right that storage is important for renewables -- fortunately grid scale batteries exist and are increasingly popular! At the end of 2020, 34% of solar projects under development were being co-located with battery storage in the US. [1]
If you're curious, Bloomberg has a nice summary [2] where they talk about how much more battery storage the world will need in a future that relies heavily on renewables (it's a lot -- see page 4 specifically).
Tracking solar systems can deliver 5-hours of generation. Solar and wind is for super cheap bulk energy. Solar is delivering the cheapest energy in history. Then we use a portfolio of other resources for balancing - grid interconnections; short and long-duration storage including pumped hydro; load flex; and bio-fuel, electro-fuel, and natural gas generators very occasionally.
