I think the source of this is that going at slower speeds is more efficient in the Tesla. It has a fixed gear[1], so you don't gain anything by going faster, yo

I think the source of this is that going at slower speeds is more efficient in the Tesla. It has a fixed gear[1], so you don't gain anything by going faster, you just lose more energy to air friction. If the regenerative breaking performs well enough, it's possible that driving off the highway will be more efficient. [1]http://en.wikipedia.org/wiki/Tesla_Roadster#Transmission http://en.wikipedia.org/wiki/Tesla_Roadster#Transmission