At a solar facility in Georgia, Silicon Ranch stores substation transformers it expects to deploy in the region in one to two years. To Nick de Vries, chief technology officer at the solar-energy developer Silicon Ranch, a transformer is like an interstate on-ramp: It boosts the voltage of the electricity that his solar plants generate to match the voltage of grid transmission lines. “They’re your ticket to ride,” says de Vries. “If you don’t have your high-voltage transformer, you don’t have a ...