What is the difference in cost between a bidirectional charger and a home backup battery such as the Tesla Powerwall 3?

A bidirectional charger enables you to access a superior home backup battery (via your EV) at a fraction of the cost of the Tesla Powerwall 3 and similar systems on the market.

The all-in cost to access your powerful Kia EV9 battery through a bidirectional charger is 55%-73% lower, while your Kia EV9 battery offers 4.5x-6x the backup power of a single 13.5 kWh Tesla Powerwall 3. (The standard range battery offers 76.1 kWh of power, and long-range models offer 99.8 kWh.) Even at the maximum configuration of 4 Powerwalls (a total of 54 kWh), your EV offers between 13%-48% more the backup time than the Powerwall. 

This equates to up to several days of additional backup power, and if you needed, your EV9’s “battery on wheels” could theoretically drive to a public charger in an area with available grid power to top up your EV battery during an outage – an option not available with a stationary battery installed on your home.

(Note that your EV does not permit third-party battery discharge below 20% state of charge. The above figures reflect this maximum power available.)