highway is a road with a higher speedlimit, or where trafic is going faster, state highways are 55mph, Interstate freeway is 65mph in wisconsin.
but mostly, to me, highway driving is 10+ miles at a consistant speed on a reasonably gental road, 90% of my driving is highway, 65mph for hours at a time without slowing down or stoping.
Here is the problem with the perception: Because MPG is calculated on "miles" vs "time spent in car", we clock 80% of our miles on the highway. Therefore, we should spend more attention for Highway's MPG testing and ratings. Unfortunately, we are sort of cheated of this. EPA relies on Drag Coefficients supplied by the Manufacturers and the simulation does not take the front license plate into consideration. The data is flawed and tests are flawed; even the new revised tests. They now talk about A/C, but they totally ignore the Aerodynamics.
Imagine: a plane with a dinner plate attached to the nose. No way, the plane cannot take off.
I think here is an ideal solution that will make an impact and have people think while making an environmental statement and costs less than a gallon of gas per vehicle. (and about as much as Dunkin Donuts coffee).
perception plays a very big part of estimated % of miles driven.
i estimate 35%city/65%hwy in my application. the "areas" driven are nearly precise, meaning city miles are driven in the city and hwy miles are driven on the hwy. however, in the city, i take many back roads w/ fewer stops and traffic signals.
so, it becomes complex when say for example...
the traffic lights that i cannot avoid are memorized(cycles), so often times i am able to make all green lights(no stopping) especially in the morning. so, in theory of "hwy driving has few or no stops", much of my city driving would have to be classified as hwy.
add to this my "back road" driving, my days driven to work consist of VERY few stops. and roll-thru is a part of some "supposed" stops as well.
my days off running errands, that is where my challenge lies. EOC helps there, altho i'm only doing it at trip end right now.
around me i consider highway 55mph and above and only stopping/slowing because of the rare traffic light every 8 miles or so. city i consider when every blocktheres a light or stop sign. id say my daily comute to school and back is 100% 55mph highway. but id say my weeky stuff is about 80% highway rest is city.