Hydrogen cars celebrate half a century; have they made a difference?

GM Electrovan fuel-cell prototype, 1966Electric cars are virtually as old as the auto industry, but hydrogen fuel-cell vehicles are not. In fact, exactly fifty years ago this month, GM showed off the first one, which it called the Electrovan. This remarkable and innovative prototype for a zero-emission vehicle used the body of an adapted GMC Handi-Van, containing the first fuel cell...