Decades ago, some unhappy Angeleno wondered why cars couldn’t just run on nice, clean … water? Not for want of trying – cleaner power has created lots of engine experiments, most dramatically Caltech versus MIT in the great electric car race of 1968, a story you’ll hear from the winner. Not all is fresh air and plug-ins: smog has been especially devastating on communities of color, and the Trump administration may pull the plug on that have let California clear its own air.