Featured Rethinking long distance driving

Discussion in 'Prius, Hybrid, EV and Alt-Fuel News' started by bwilson4web, Aug 4, 2025 at 12:10 PM.

  1. bwilson4web

    bwilson4web BMW i3 and Model 3

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    A recent 2,245 mile trip inspired benchmarking and generating this graph:
    FSD_segments.jpg
    • Drive segments lines at 40, 60, and 80 mph intersect at zero with the charge curve.
      • Limited to 3 hours (180 minutes) of driving
      • Maximum 30 minutes of charging in 10, 20, and 30 minutes
    A horizontal line from one of the three speed lines to the charge curve gives the total minutes for one driving segment, the sum of driving time and charging time. For example, driving at 80 mph for an hour:
    • -60 minutes to drive 80 mph
    • +8 minutes to charge for that distance at that speed
    • 60 + 8 = 68 minutes for that segment
    • 80 mi * (60 / 68) = 70.6 mph equivalent speed combined driving and charging
    Driving at 80 mph for an hour with required charging, the block-to-block speed will at best be 70 mph or 70 / 80 = 87.5% of the EV driving speed. This leads to a more useful summary chart.

    Here is a chart of block-to-block, speed efficiency:
    FSD_efficiency.jpg
    • 80 mph has the worst block-to-block speed efficiency, 80-87%.
    • 60 mph is better, 84.5-90.5%.
    • 40 mph is best, 100% within the 3 hour limit.
    Full Self Driving (FSD) does excellent night driving which is typically cooler and has minimum car traffic and mostly professional driven, tractor trailers. Leaving around midnight and driving for 12 hours, arrives around checkin time at a distance motel. Fortunately there are tractor trailer companies, especially moving vans, that limit their cruise speed to 65 mph. This suggests an optimal EV strategy:
    • Get on Interstate in "Chill" mode at 60 mph
    • When a truck passes at 65 mph, set "Chill" mode speed to 67 mph
    • Stay in lane to follow truck
      • Full Self Driving keeps a safe distance behind, not tailgating
        • FSD nag keeps your eyes looking for any road debris to avoid
      • Truck serves as camouflage so other traffic avoids tailgating
      • Larger truck rear lights improves visibility to following traffic
        • minimizes a rear end collision
      • WARNING - have quality anti-rock film on windshield
    • Charge at every charger on way for fastest block-to-block speed
      • Add miles to next SuperCharger plus 30-40 mile reserve
    Exit and return segments can't be helped but frequent breaks are good for the human monitoring FSD at night. A lot of miles will be covered without a lot of fatigue and minimum risk.

    Bob Wilson
     
  2. bisco

    bisco cookie crumbler

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    night driving concerns me due to unseen objects on the road
     
  3. bwilson4web

    bwilson4web BMW i3 and Model 3

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    Correct but I have tricks:
    • I follow trucks - the commercial driver sees further and higher than me.
      • Truck rear lights in addition to mine
    • FSD - cameras see better at night than humans.
      • Nags - requires the driver to look out the windshield except for short glances
      • Safe following distance - time enough to steer around debris
    These make night driving “less bad.”

    Bob Wilson
     
  4. BiomedO1

    BiomedO1 Senior Member

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    I use the same trick driving through tulie fog. The semi-rig is my battering ram. I've almost hit idiots dead stopped in the middle of the highway. I now slide behind a semi-rig; though we should've both pulled over to wait for the fog to lift or dissipate.
    I don't like pulling over, seen too many drunks plow into road crews in broad daylight under clear conditions.