This technology is obviously brilliant, and as with every major innovation, improvements will naturally evolve with each iteration.
Powerwall is a home battery that charges using electricity generated from solar panels, or when utility rates are low, and powers your home in the evening. It also fortifies your home against power outages by providing a backup electricity supply. Automated, compact and simple to install, Powerwall offers independence from the utility grid and the security of an emergency backup.
See: Elon Musk’s video presentation on Energy storage for a sustainable home here.