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Driving at 110 km/h on the highway: fuel economy and safety gains

LaRedaction Posted messages 871 Registration date   Status Administrator Last intervention   -  
brucine Posted messages 25149 Registration date   Status Member Last intervention   -
Julian Hochgesang - Unsplash
Driving at 130 km/h on the highway seems to be the norm, but lowering speed to 110 km/h could save up to 25% of fuel. Indeed, the increase in air resistance with speed makes the engine consume more energy. Real-world tests confirm this theory: over a distance of 500 km, a fuel saving of 7 liters is achieved by driving at 110 km/h instead of 130 km/h. Moreover, this speed reduction can prove even more economical for electric cars. In fact, this lower speed can, in some cases, allow arriving at the destination sooner by avoiding additional charging stops. Isn't that an interesting topic to debate for our automobile-enthusiast users?
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4 answers

  1.
    mariam-j Posted messages 1657 Registration date   Status Member Last intervention   34
     

    Hello,

    Let us leave the vehicle at the garage.

    The savings will be substantial.

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  2. Pinbot
     

    Good idea, and if we took the train we wouldn't have problems on the road; we all roll at 90 on the highway, pay a ton, and voila, everyone will be happy (not me).

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    1. brucine Posted messages 25149 Registration date   Status Member Last intervention   4 167
       

      These are merely suggestions; you retain the right to drive at 130 km/h at least in areas where the limit is not lower (suburban zones, road profile, roadworks...).

      The severity of accidents obviously increases with speed, but it’s forgetting that apart from those who drive at stratospheric speeds, which may not always be perceivable in time, speed itself is not directly the cause of the accident (various psychoactive substances, drowsiness, various imprudences, of which often the failure to respect safe following distances).

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  3. Duchnock
     

    It all depends on the vehicle: I drive in Portugal where the highway speed limit is 120 km/h, but what I notice is that I often drive at 110 km/h, and at that speed my vehicle, a Mercedes GLC 220 D with a 9-speed automatic transmission, often downshifts to 8th gear. As a result, instead of 1400 RPM, the tachometer drops to 200 RPM, which is not good for my fuel consumption. The best for me is to drive at 120, and thus, except in mountains, I stay at 1400 rpm.

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    1. brupala Posted messages 111174 Registration date   Status Member Last intervention   14 455
       

      Hi

      why do I have a Kangoo?

      That said, the 120s, it handles them easily ... ;-)

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      1. brucine Posted messages 25149 Registration date   Status Member Last intervention   4 167 > brupala Posted messages 111174 Registration date   Status Member Last intervention  
         

        Hello,

        In any case, the demonstration leaves me speechless.

        It would be necessary to quantify for us the overconsumption of an episodic passage at 200 extra revs on a very low regime (diesel engine).

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      2. brucine Posted messages 25149 Registration date   Status Member Last intervention   4 167 > brucine Posted messages 25149 Registration date   Status Member Last intervention  
         
        In more general terms, we have an overweight tank, but whose engine isn’t that big and whose consumption is anyway reasonable given that it’s a diesel. The manufacturer's idea of wanting to reduce it further with a 9-speed gearbox, apart from what we don’t know about its relevance for a vehicle at this price, necessarily relies on the fact that the last three gears are unnecessary and are under- or over-multiplied relative to the engine’s size and power, with not only the very theoretical consequences mentioned but also discomfort and/or an impact on acceleration resulting from these abrupt gear changes. So it’s not the speed limit or cruising speed that are at issue and could be other, but the design of the car.
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  4. Sylvain_LD Posted messages 31 Registration date   Status Member Last intervention   3
     

    Not driving fast also helps to tire less. Those who drive fast don't necessarily realize it, but it requires more attention, which leads to more fatigue in the end!

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