The most profitable corner of the booming U.S. solar industry isn’t making -- or even installing -- panels. It’s building the components that keep electricity flowing to the power grid.
They’re called inverters, and the two companies that make the vast majority of premium ones in the U.S. reported their highest revenue ever in the second quarter, propelling their shares to record levels. Enphase Energy Inc., has gone from trading at less than a dollar to ranking among the world’s most valuable solar stocks with a market capitalization of $3.8 billion. Its slightly larger rival, SolarEdge Technologies Inc., has rallied 129% this year.