Sierra solar can be easily supplemented by valley solar in winter. No need for long distance transmission.This is really superb and needs to spread elsewhere. A great goal for the rest of us.
According to your sig it looks like you live in Florida? How many Powerwalls?
Florida is one of the best places in the U.S. to see this takeoff with the most successful use of renewables + demand management with grid utilization minimization. SoCal and a few others in the southwest are probably close seconds.
FL and very south Texas are closest to the equator, so have the least variation in solar radiance throughout the year - a big advantage for home solar PV and heat pumps with the least need for home/grid batteries. Mild FL winters also are a big advantage. Further, the risks of edge cases like blizzards which require a robust grid has the least risk in such a location.
Looking to the future for the higher latitudes and elevations in my state - using our weather scenario from the last couple of weeks in mid/northern CA in the foothills and mountains and considering heat pumps as the future for home HVAC and water needs:
We are currently near the winter solstice and with the blizzards that just went through here, there was little solar irradiance and very high energy needs for many consecutive days (profoundly inverting their maximal season solar PV production:energy use ratio). This means these areas will remain deeply dependent on the grid for the foreseeable future - for these not-so-edge cases alone. But, fire risks from transmission to these areas aside and the lack of local internalization of these costs, this is ok as those residents can be served by the import of renewables from far away such as offshore wind, TX/midwest wind, southwest solar PV, and pacific northwest hydro.