Here is the link to the article from Green Tech Media... http://www.greentechmedia.com/articles/read/ten-green-ideas-that-may-never-take-flight/
I do not succumb to the authors views on automobiles (3 wheeled cars and battery swaping stations could be feasible). There is not enough data to write them off even before they have their fair chance.
Nevertheless an interesting read.
Happy Winter Solstice
22 hours ago