The real costs of 80 vs 55 mph

[redpoint5]

Waste is subjective. Should I shame people who do 50 because they could spend half the energy doing 30?

80 is at the boundary of what I find acceptable personally. What if the person doing 80 is in an EV? They are more efficient than a dually F350 at any speed.

The point of traveling is to arrive at the destination. The less I've aged in that process, the better.

[Isaac Zachary]

Originally Posted by Caddylackn

You can design and build the safest intersection in the world with flashing lights and narrowed road, safety bulb outs, etc. and some idiot who is high will cross the street in front of the car at night dressed in black and get hit and still sue the driver and possibly the Engineer.

What if you have 6 neighbors that have been hit, 4 of them killed, as they either walked or rode their bike, and only one was in the wrong? Do I even dare walk or ride my bike? My job is almost exacly one mile away, 20 minutes walking and easily 10 minutes or less riding a bike. I'm also getting about 20mpg or less right now in the hybrid Avalon. But I don't want to die just because everyone else drives like an idiot.

[redpoint5]

I attempt to live statistically, not anecdotally, to the extent I can manage.

[JDaly]

Originally Posted by Caddylackn

People who speed tailgate other drivers doing the speed they want to drive so slower drivers do not pull out in front of them.

Amazing. I wondered why those crazies were driving 5 ft behind the forward cars bumber at 74 mph. !! This makes sense. Also, great points about the higher costs of speeding - very true.

Originally Posted by Caddylackn

I have been doing road design and Civil Engineering for years. You cannot Engineer out the stupidity of drivers or pedestrians or slow people who want to speed.

Thank you for your civil engineering efforts to improve our built environment. You and your colleagues HAVE made a difference and we appreciate that. But yes the inevitable foolishness of a portion of our populace must dishearten you, all.

But I have noticed things like raised bump up red crosswalks make a difference.
Consider Netherlands (always consider Netherlands):

"In the Netherlands, the sustainable safety approach differs from Vision Zero in that it acknowledges that in the majority of accidents humans are to blame [emphasis mine], and that roads should be designed to be "self-explaining" thus reducing the likelihood of crashes. Self-explaining roads are easy to use and navigate, it being self-evident to road users where they should be and how they should behave. The Dutch also prevent dangerous differences in mass, speeds and/or directions from mixing. Roundabouts create crossings on an otherwise 50 km/h (31 mph) road that are slow enough, 30 km/h (19 mph), to permit pedestrians and cyclists to cross in safety. Mopeds, cyclists and pedestrians are kept away from cars on separate paths above 30 km/h (19 mph) in the built up area. Buses are also often given dedicated lanes, preventing their large mass from conflicting with low mass ordinary cars.

More recently the Dutch have introduced the idea that roads should also be "forgiving", i.e. designed to lessen the outcome of a traffic collision when the inevitable does occur, principles which are at the core of both the Dutch and Swedish policies.[33]

-- from Wikipedia entry on Vision Zero

PS I think this thread has morphed from aerodynamics to "general efficiency" and not sure how to deal with that.

[JDaly]

Originally Posted by Isaac Zachary

What if you have 6 neighbors that have been hit, 4 of them killed, as they either walked or rode their bike, and only one was in the wrong? Do I even dare walk or ride my bike?.

Yikes. You are scaring me. I ride my Yamaha Cross Connect eBike EVERYWHERE and I am mixing with the "bigs" - cars, trucks, etc. I am lit up with every light and neon green overlays and ride safely but friends and recently my primary physician are shaking their head at me. Maybe I have just been lucky doing this for now !!! 52 years. Prob'ly so.

[Isaac Zachary]

Originally Posted by JDaly

Yikes. You are scaring me. I ride my Yamaha Cross Connect eBike EVERYWHERE and I am mixing with the "bigs" - cars, trucks, etc. I am lit up with every light and neon green overlays and ride safely but friends and recently my primary physician are shaking their head at me. Maybe I have just been lucky doing this for now !!! 52 years. Prob'ly so.

That is one thing that would probably help is just being seen. One of the neighbor ladies that got killed liked to wear all black. A guy was turning left and as soon as he had a green light he ran right over her in the crosswalk. She was in the adjacent crosswalk with the rightaway, but it also happened at night, so she was hard to see.

[JDaly]

Originally Posted by Isaac Zachary

That is one thing that would probably help is just being seen.

Thanks. Breathing easier.

[freebeard]

While the doctors are fussing over my INR ratio, I tell them I'm in more danger from the trip to and from the clinic.

I have been wanting an Arcimoto FUV for it's cage, but there goes the exercise. Their micromobility solution, when it comes will be more lethal than a bicycle, zippy with hard cornering capability.

[Phase]

Originally Posted by Isaac Zachary

That is one thing that would probably help is just being seen. One of the neighbor ladies that got killed liked to wear all black. A guy was turning left and as soon as he had a green light he ran right over her in the crosswalk. She was in the adjacent crosswalk with the rightaway, but it also happened at night, so she was hard to see.

I’m
Surprised all that happens in gunnison. Stayed there in February to go ride at crested butte and it’s one of the smallest cities in Colorado I’ve ever stayed in. Barely even had an Arby’s to eat at or real grocery stores. I’m assuming it’s tourists who are doing the bad driving when in town.

[Phase]

Originally Posted by JDaly

Good additions. I just took the model's output at face value and graphed it. Twould make sense that Rolling Resistance increases a little as more friction would indicate. Also interesting on the no wind resistance until 37 mph. I have often heard that 45 or so is the most efficient speed and the 37 would support that. But I know from riding my bike that wind resistance DOES increase from about 5 mph and up. By 20 MPH I can really feel it. (Empirical evidence).
Thanks for the corrections.
JDaly

PS. I am getting grief from friends who drive a lot who say they'd go crazy driving any slower than 65 MPh. Think driving from Boston to Buffalo like that.

45 is probably a little more efficient than 50, especially with low rolling resistance tires. I only did a steady state run for 20 miles in my Ioniq at 50mph with cc on and I was getting 87-94mpg on my trip reader. I was also ticking off 18 wheelers having to pass me in the right lane on the interstate on that test run. If I did 45 with cc on, my cars mpg reader would probably just say 99.9 the whole time and I’d never know how high it gets. Either way, going 50 and getting over 90mpg is fine. I’m not so cheap where I’d have to drop down to 45mpg to save even more money in my Ioniq…