I think the evangalists need to be careful with their historical 'learnings'.
The reason technologies like the motor car and internal combustion in general advanced as rapidly and as far as they have is because technology 'savvy' people could see those nascent technologies offered great potential.
They meant that greater power, less weight, more speed etc were potentially on offer.
The situation with all 'green technology' is fundementally different. In the vast majority of cases large costs and other significant disadvantages means that the 'green' version will under perform the present situation until there is either a massive technical breakthrough or legislative or some other external influence.
In short it is the Prius argument - it looks good for the planet but actually it is not green, it promises fuel economy but does not delivery, it is not genuinely sustainable - it is marketing.
I know a chap with an electric glider - it is a thing of beauty - the best our technology can offer at the moment. It self launches and can climb to 3000m - once. It can give full throttle for 13 minutes - after which it can 'self sustain' for maybe another 10 - if the cells recover. He has had some problems with the cells but loves the idea of the machine.
List price is just short of $300,000 so it carries some pretty significant downsides. Incidentally the manufacturers say there is no point in using solar cells to increase the self sustaining mode - too heavy, too little power......