There are advances to be made, certainly, but flywheels may be better used at a smaller level, such as for neighborhoods or in each house, itself perhaps having a solar PV roof or panels placed elsewhere. An integrated solution can be widely distributed instead of centralized.
Originally Posted by primummobile
I'd expect them to do better in the summer with more sun-time, if the angle allows enough of the suitable wavelengths through. In the winter you know it won't operate, so put it in storage and go with something else, like nuclear, and use a combined Heat and Electricity solution to make it even more efficient.
As for building large solar farms at certain latitudes....
Et tu BAUT? Quantum mutatus ab illo.