Solar power is becoming more cost effective by the day, and some of the biggest companies in the U.S. are buying into its potential. Wal-Mart (WMT +0.09%), Costco (COST +1.68%), and Apple (AAPL 0.04%) are now three of the biggest corporate solar installers in the U.S., and they continue to build more solar every year.
How can investors play this? SolarCity (SCTY +0.00%) and SunPower (SPWR +0.00%) are the two biggest players in commercial solar, with SolarCity partnering with Wal-Mart and Apple using SunPower's technology. Erin Miller sat down with solar analyst Travis Hoium to learn more about this trend in the solar industry.





