Trick engineering from the General here. Much of the polution caused by EV's is actually baked into the mining of rare earth minerals for use in the batteries and motors.
Original source http://blogs.motortrend.com/1504_dissecting_chevys_2nd_gen_moonshot_technologue.html
http://gmauthority.com/blog/2015/05/motor-trend-dissects-the-2016-volt-powertrain/First off, Motor Trend reports that the smaller motor in the General Motors Voltec 2.0 powertrain eliminates rare earth materials altogether by using simple ferrite magnets. These magnets are optimized by their arrangement into a dozen regularly-spaced clusters encircling the central rotor, with each cluster containing four concentric elements. This allows for a maximization of both magnetic, and reluctance (or “magnetic resistance”) torque.
The larger motor, meanwhile, does contain a rare earth metal in the form of the element Dysprosium, but its presence is reduced thanks to some clever engineering. Says Motor Trend, a trick of metallurgy concentrates the Dysprosium into the corners of the larger motor’s magnetic elements, where it’s most effective. Together, not only do the complimentary motors of the new Voltec powertrain manage to use 80 percent less rare earth metals, but they also prove to be ideal counterparts in the revised system. The small motor hits peak efficiency at 5-9k RPM, at relatively lower torque, while the larger motor peaks in efficiency at higher torque, at around 2-4k RPM.
Original source http://blogs.motortrend.com/1504_dissecting_chevys_2nd_gen_moonshot_technologue.html