Quote:
Originally Posted by VaBeachPrius
In layman's terms, the point is to slow down. Driving slowly and accelerating slowly (without blocking traffic) is a great way for the individual to anticipate traffic, traffic signals, and to be left alone (mostly) by other cars (they will pass).
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More precisely, the speed and vehicle drag ultimately dictates how much energy is needed to move over any given distance. The trick is avoiding inefficiencies, energy losses, while maximizing ICE efficiency.
Quote:
Originally Posted by VaBeachPrius
It is one thing to get 70 mpg on a closed portion of roadway and another to get the same or higher with traffic and lights. Conciously picking roads with slow speed limits can yield values close to 100 mpg. It would for me to just set the cruise control and just go.
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Exactly, the primary determinant is speed. Clever route planning where the low-speed segments are also short-cuts, leads to excellent MPG without a commute time penalty.
Quote:
Originally Posted by VaBeachPrius
. . . That is where pulse and glide tied into anticipation of traffic yields excellent results in everyday driving.
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Someday we must perform the following experiment:
- Drive a fixed route using "pulse and glide"
- Drive the same route using constant speed
Fortunately, it is easy to modify the described protocol to accomplish that end.
I have a graduated cylinder coming that with a fuel pump, filter and some piping will allow precise measurement of vehicle fuel efficiency over reasonable intervals. Then it will be easy to perform a well defined, 'pulse and glide' benchmark followed by a constant speed test using the average speed of the 'pulse and glide'.
So the only question remaining is what pulse and glide protocol should be used for an average speed of say, ~15
mph?
- 20-10 mph
- 25-5 mph
- 30-0 mph
This is just a math problem.
Bob Wilson