In reply to Michel Jullian's message of Sat, 2 Aug 2008 00:12:17 +0200: Hi, [snip] >You may be right for gas cars, but the sweet spot will be much lower for cars >that don't have to consume power at zero speed. See: > >http://auto.howstuffworks.com/question477.htm > ><<...But the bottom line is, if you double your speed, this equation says that >you will increase the power required by much more than double. A hypothetical >medium sized SUV that requires 20 horsepower at 50 mph might require 100 >horsepower at 100 mph. >You can also see from the equation that if the velocity v is 0, the power >required is also 0. If the velocity is very small then the power required is >also very small. So you might be thinking that you would get the best mileage >at a really slow speed like 1 mph. >But there is something going on in the engine that eliminates this theory. If >your car is going 0 mph your engine is still running...>> > >So I am still far from convinced that that tiny van can't possibly go 200 km >in 10 h on 12 kWh mechanical energy. At constant 20 km/h this would mean 1.2 >kW for 10 h, it doesn't sound totally impossible to me that two 600W power >drills could propel that thing at this kind of speed... That's about he speed of a horse and buggy, the weight and power of which would be about the same.
Regards, Robin van Spaandonk <[EMAIL PROTECTED]>
