When Tesla unveiled its new Powerwall home battery, I don't think most people thought it would take off as fast as it has. According to Bloomberg, Tesla has received over $800 million in orders for the Powerwall and Powerpack batteries so far.
The site says that Tesla has received around $179 million worth of Powerwall reservations so far, with $625 million worth of Powerpack reservations to boot. Tesla has already said that it's taken in around 38,000 total reservations for Powerwall, and 2,500 reservations for Powerpack.
Tesla is selling the Powerwall for $3000 and $3500 for the 7kWh and 10kWh models, respectively. Powerpack units make even more money for Tesla, as they're being sold to businesses and utilities for power storage for $250 per kilowatt hour to use.