S&C Electric Company is in the thick of the battle for the grid-scale energy storage market. It's an emerging multi-billion-dollar market, and much of the territory is still up for grabs. Do competitors need to be small, agile specialists like software-intensive integrators Greensmith or Stem? Or is the vertical integration of firms like leaders S&C or AES (a la SolarCity in solar) the optimum way to approach this emerging market? Is being a battery maker the best way to get to market? And how long until energy storage is a material part of the energy picture?