Optimum Highway Speed

Personally with two up, I find 55mph to be best for economy. It's too slow tho when the traffic is busy and you just become another rolling road block, so on the highways (UK Motorways) I drive at 60mph for mileage and 70 for speed. Above 65 your mileage really takes a hit! Hope that helps you little bit.

 

On my recent road trip of 500 miles of USA Interstate Highways: 65-70 mph is maximum speed for any kind of decent mileage. Above 70 mph and efficiency declines rapidly. Optimum seems to be about 50-55 mph but I usually drive the speed limit plus 5 mph to avoid getting run over. After this road trip I won't exceed 70 mph no matter what the road is posted at.

 

As noted above, 65mph is about the limit for reasonable mileage. If you insist on driving slower than the traffic, do so behind a truck or other slow moving vehicle. Prius drivers already have enough "haters" out there. Personally, I drive 3-5mph over the limit and suffer the low mileage. Freeway driving is not the place to try to hyper-mile.

 

As far the best mpg on the highway, the slower the better. 60 mph will have better mpg than 62. And 55 mph even better.

Doesn't mean that you should drive that speed- I personally drive 3-5 mph over the highway speed limit in the slow lane. In real life, it's hard to determine that optimum highway speed without including what the speed limit is. Highways in my town range from 55-70 mph.

 

I just do the speed limit, set the active cruise and relax. I used to speed but there are too many cameras around now.


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53mph is the ideal speed. I cannot comply with that speed and models of efficiency lead to acts of inefficiency thus flow of traffic is the ideal speed.

 

Just curious, are you referring to cameras that will take photos of your license plate and will blindly send a speeding ticket to your home? (We used to have red light cameras that did that in some towns in California- it was brutal.)

 

In the uk we have cameras that take pictures and create a ticket. These are either one off speed measurements or average over miles and miles of motorway.


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A couple years ago, I got to spend two weeks in Yorkshire and really enjoyed driving under those conditions. For the most part, I could set the cruise control and know that some bonehead in an SUV wouldn't be riding my bumper and flipping the bird because I was committing the heinous crime of obeying the law. Which was really nice since I was learning how to drive on the other side of the road!!

 

Got it, thanks. I saw signs for that when I was driving on a business trip in Taiwan.

Years ago, I would have thought those things would have been the worst things imaginable. Nowadays, as jerrymildred wrote, it would simply enforce speed limits. That's something that I'd welcome- wow, I must be getting old.

 

First, you must define just what you mean by 'maximum Optimum Highway Speed'.

Do you mean maximum MPG? For every Prius generation, this should be the lowest highway speed that you find acceptable for the conditions and your particular needs.

If that is the wrong answer, then you need to better define the question.

 

Yes sir, the speed cameras impose an automatic £100 fine and add 3 points to your driving licence. Points are cumulative and you lose your licence to drive if the total is 12 or more within 3 years.

 

Plano almost proudly declares itself a red light camera enforced city.

Most major intersections have cameras, which is probably a good thing, considering the propensity for natives to drive like bats out of hell (or worse).

Blow a light, get a ticket. Don't pay, get a warrant.

The insurance industry considers Texas drivers the worst in the US.

Natives apparently gravitate to the cities, but I'm not sure why the influx of large numbers of outsiders hasn't seemed to dilute the bad driver population in the past n years. My sister, who's lived here over 10 years, still complains about crappy Texas drivers.

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I see what you're asking. On the gen 3, the drop in mpg from increasing 60 to 65 mph is smaller than the drop in mpg from 65 to 70 mph.

On the gen 3, it appears that the larger reduction in mpg occurs at 75 mph. From 75 to 80 mpg, the fuel economy drops 10 mpg (from 50 to 40). But 75 mph isn't the sweet spot by any means.

 

Many intersections have cameras because that is where the majority of accident happen. As you know, these aren't red light cameras. You mentioned "almost" became a red light camera city? Does that mean they never arrived? Because they are unpleasant.

I had some in my area when I lived in SoCal. The local community intends the camera to be a means to increase safety and encourage motorists to obey traffic signals. The red light camera companies have the opposite goals- they want the motorists to get tickets. First order of business is to drastically reduce the yellow light period to the minimum allowable time- sometimes less. 2nd order of business was to dramatically increase the cost of running a red light. This was so the red light camera companies could get their cut and this was primarily how they made their money.

This even made intersections more dangerous as motorists would slam on their brakes to avoid a dreaded red light ticket. Los Angeles county declared that there would be no penalty to motorists if they blew off the ticket under the idea that they never received it. However, if the motorist acknowledged receipt of the ticket, they had to pay. It was controversial, to say the least, and some politicians used getting rid of the cameras as part of their campaign platform.

Just curious as a general question...is there a city that uses cameras to hand out tickets for speeding in the US?

(sorry for the hijack)

 

The incomers must be adapting to survive amongst the locals!

 

Many trucking companies have a maximum governed speed of 62 mph and I can verify that setting the cruise for 62 will eventually put you behind one or more of those semi trucks in the slow lane.