BMW customers have two ways of charging their iX at home, the fastest being by installing a three-phase 22kW AC wall charger. These cost between $1500 to $3000, with additional energy costs averaging between 21-36 cents per kW, depending on your provider and which state you live in. If you’re hooked up to solar power, the additional cost can be zero. According to BMW, this method will charge the iX xDrive40 from 0-100 per cent in 8 hours and 15 minutes. The other method is a standard AC wall socket, which charges at a much slower rate of 2.3kW. BMW says this will take 39 hours for a full charge.