Yes the battery is charged by solar, however it can also be fed by the grind if you wanted to for some random reason. The DC power runs to the inverter from your panels than once converted to AC power it charges the battery. You can monitor the power draw of your house and the amount of solar energy collected through an App on your phone or computer. Companies like Tesla have solar and batterie packages for sale on their website, but I know the solar company SunRun also sells and installs Teslas Power Walls with their own solar arrays.