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Honda says making cheap electric vehicles is too hard, ends deal with GM
(arstechnica.com)
This is a most excellent place for technology news and articles.
Last I looked into it, Toyota was still supposed to have some of the most efficient combustion engines out there, with something crazy like 40%(?) thermal efficiency.
Wow, 56%, impressive, although they seem to be roughly in-line with the competition for MPG anyway.
It's because fuel economy is heavily driven by vehicle weight, since start from a stop kills efficiency. Cruise effeciency is more about aerodynamics than weight (ask anyone who's ever towed anything - you can really feel the drag above 45mph).
And oddly enough, today's cars aren't really significantly lighter than 30 or 40 years ago. We've just moved the weight from the frame/body setup to unitized body/frame (lighter but safer... And cheaper to manufacture), more safety systems (airbags/computers) and things like heated seats, etc.
Today's 4+ seat SUV often weighs as much as a 1970's 4+ seat station wagon...but with less space inside.
How do they pull that off?
How efficient was the Flying Scotsman? That must have had a pretty efficient engine.
At a quick google steam locomotives generally top out at 10%, due to discarding the steam without recovering any of the heat.