I agree, petrol cars will go the way of the dinosaur eventually, and if M-B have researched this, I have faith it will be worthwhile.
The potential for economy is greater for a bigger, more powerful car.
My beef with the Prius is it was just a marketing led gimmick, which plays to the Holier-Than-Thou mentality of the Greenies without actully delivering anything.
If you must have a Toyota, a standard Corolla hatchback will be fuel efficient without the dodgy electrics.
There are many forums out there with stories of exploding lithium batteries, battery failure after three years, and they can be a couple of thousand dollars to replace, and also, the Prius is not competitively priced for what it is.
And what hidden carbon cost in the manufacturing?
I guess I just don't like hypocracy.
Now, the only FREE and renewable energy sources available to us at the moment are Solar and Wind. If a modern day Edison can make either of those generate efficient quantities of power, we can happily go back to the electric car with totally green conciences.
Meanwhile, I highly recommend reading 'Taking Charge - The Electric Automobile In America' by Michael Brian Schiffer as an education on how the petrol car came to prominence over the electric in the early years of the 20th century, and developments since.
Chris M.