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PrecisionmachinisT PrecisionmachinisT is offline
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Default Motor size and efficiency: both gas and electric


"Jon Elson" wrote in message ...
PrecisionmachinisT wrote:


Electric motors generally convert nearly all of the input energy into
work, internal combustion engines very rarely approach even 40%


40%? A typical Otto-cycle engine gets about 13% efficiency at its best
operating point, which is near full throttle (to get high cylinder
temperatures and low pumping loss).

The Honda Civic Hybrid variable-cycle semi-Atkinson cycle engine does
much better at a lower power setting. They optimized it so it does
best at constant-speed cruise on a level road. I don't know of any
other production auto engines that work like that.



All of which explains why I said "very rarely approach even 40%"