Tesla unveils Powerwall home battery

Tesla Motors unveiled its new Powerwall home battery Thursday, sending Long Island energy experts abuzz.
The batteries can act as a backup system in the case of blackouts by storing the energy produced from solar panels. They can also store energy from the grid.
According to Tesla's website, Powerwall offers "independence from the utility grid and the security of an emergency backup."
The home battery will cost between $3,000 to $13,000.