The solar industry is rapidly vertically integrating, highlighted by SolarCity's (SCTY.DL) acquisition of Silevo last week. As it does, there will be a few companies emerging with the capabilities to add value for consumers from the panel to financing projects. 

SolarCity clearly has a lead and with modules now coming under its control the company owns nearly the entire supply chain. This will allow it to integrate systems easily and lower balance of system costs. 

SunPower (SPWR 5.85%) is leveraging a high efficiency panel to lower balance of system costs and is adding to its financing capabilities as well. With experience installing large and small systems around the world this will be an industry leader for years to come. 

The big company to keep an eye on is NRG Energy (NRG -0.07%), who is leveraging its utility scale to get into residential solar on top of owning large systems. If there's one utility with the vision to get residential solar right it's NRG. 

Solar specialist Travis Hoium covers how you should play this booming industry in the video below.