Formula E's second season is a litmus test. Now is when the championship starts to prove its credentials as both a development hub for electric-vehicle technology and a legitimate, popular worldwide racing series.
But the ultimate challenge is facing the 10 Formula E teams: design and build new technology, get it working, get it optimised, and make sure you're not frying your batteries. Or at least a variation of those factors.
It's still the very beginning of a journey that will ultimately be defined by development of new technologies, but retains an old-school competition element as well.