As we move through earnings season in the solar industry, it's very apparent that not all companies can be treated the same by investors. For example, SunPower (NASDAQ:SPWR) and First Solar (NASDAQ:FSLR) are the two major U.S. companies that are profitable but SunPower margins are on the rise while First Solar's are falling. 

In the residential market, SolarCity (NASDAQ:SCTY.DL) is expecting to grow nearly 90% this year but a shift to sales instead of leases may affect profits. Nipping on its heels is SunPower, which has quietly become the second-largest residential solar company in the country. 

In the video below, solar analyst Travis Hoium discusses what we've learned from solar earnings so far. 

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