Quick Take: We advise caution on this new V2G forecast.This report lumps together V2G (cars supply electricity directly to the grid) with smart charging (cars stop and start their charge cycles to match the grid's needs). The former is  highly unlikely since repeated discharge cycles would degrade the batteries, the most expensive and "fragile" part of an EV. The latter is the right approach, but requires interoperability. Sadly, the industry is foolishly embarking on dozens of incompatible islands of EV charging without central coordination. As a result, electric vehicles could endanger unsuspecting utilities. We're EV fans and supporters, but we also have the job of warning you of problems and obstacles. Before you make up your mind, you may want to review this overview of electric vehicle charging incompatibility issues. And this warning from one firm that electric vehicle growth may be slower than hoped.    – Jesse Berst